JP7388147B2 - Post-processing equipment and printing system - Google Patents

Description

The present invention relates to a post-processing device and a printing system for processing printed media.

Patent Document 1 discloses a processing tray as an example of an intermediate tray on which transported media is loaded and output processing is performed, and a retracting member that moves perpendicularly to the medium loading surface of the processing tray to drive the medium. and end alignment means as an example. Further, the edge alignment means has a trailing edge alignment portion that is a surface that the edge of the medium comes into contact with when the medium is drawn in, and the edge alignment means detects the height of the trailing edge of the medium by detecting the height of the trailing edge of the medium. A post-processing device is disclosed that has a control means for controlling a drive means based on.

Japanese Patent Application Publication No. 2011-093632

In the printing section of a printing device, printing is performed on media of various materials and basis weights, and the friction coefficient of the media may change depending on the printing method. For example, in a liquid ejection method as an example of the printing section of a printing device, liquid is ejected onto paper, which is an example of a printed medium, which increases the moisture content of the paper and changes the coefficient of friction between the sheets. do.

Generally, an elastic member with a high coefficient of friction is used as a pull-in member for aligning the paper with the trailing edge alignment section. When aligning sheets that contain water to the intermediate tray, the coefficient of friction between the sheets becomes higher than when aligning sheets that do not contain water. When pulling in water-containing paper, the coefficient of friction between the paper being pulled in and the paper already loaded on the intermediate tray increases, so even though the trailing edge height of the media is low, the pulling member may The required pulling force increases. Therefore, it takes a long time for the end of the medium to reach the rear end alignment section.

In the post-processing device described in Patent Document 1, the driving means of the drawing member is controlled based on the detection result of the medium trailing edge height detecting means, and the drawing member transports the medium for a predetermined period of time, thereby removing the medium. is pulled into the rear end alignment section. However, depending on the moisture content of the medium printed by the printing unit of the printing device, there is a possibility that the trailing edge of the medium may not reach the trailing edge alignment portion within a predetermined period of time.

A post-processing device that solves the above problems includes: a conveyance path that conveys a medium printed with a liquid discharged by a liquid discharge unit included in a printing device; and an intermediate tray on which the medium conveyed by the conveyance path is loaded. a first drawing member that is provided on the intermediate tray and starts a first drawing operation that draws the medium toward the upstream side in the transport direction after the rear end of the medium passes through the transport path; a rear end aligning part that contacts the rear end of the medium drawn in by the first drawing member and aligns the rear end of the medium; and a control part that controls the operation of the first drawing member, The control unit is configured to control the control unit when a first cumulative number of rotations after starting the first retraction operation reaches a first required number of rotations necessary for aligning the rear end of the medium with the rear end alignment portion. The control unit is configured to regulate the first retracting operation, and the control unit determines the first required rotation speed according to parameter conditions.

A printing system that solves the above problems includes a conveyance path that conveys a medium printed with liquid discharged by a liquid discharge section, an intermediate tray on which the medium conveyed by the conveyance path is loaded, and a conveyance path provided on the intermediate tray. a first pull-in member that starts a first pull-in operation to pull the medium upstream in the conveyance direction after the rear end of the medium passes through the conveyance path; a trailing edge aligning section that contacts and aligns the trailing end of the medium pulled in by the medium; and a control section that controls the operation of the first drawing member, the control section comprising: The first pulling operation is performed when the first cumulative number of rotations since the start of the first pulling operation reaches the first necessary number of rotations necessary for aligning the rear end of the medium with the rear end alignment part. The controller is configured to regulate the first required rotation speed according to parameter conditions.

FIG. 1 is a schematic side view showing a printing system in one embodiment. FIG. 3 is a schematic side view showing the state of the post-processing device when discharging the medium to the intermediate tray. FIG. 3 is a schematic side view showing the state of the post-processing device immediately before completing ejection of the medium onto the intermediate tray. FIG. 7 is a schematic side view showing the state of the post-processing device when the second drawing member starts drawing the medium. FIG. 7 is a schematic side view showing the state of the post-processing device when the second drawing member draws in the medium. FIG. 3 is a schematic side view showing the state of the post-processing device when the first drawing member and the second drawing member draw the medium. FIG. 3 is a schematic side view showing the state of the post-processing device when the first drawing member aligns the medium with the rear end alignment section. FIG. 3 is a schematic side view showing the state of the post-processing device when alignment of the media is completed. FIG. 6 is a timing chart showing the operation of the post-processing device when the first retracting member changes to the second posture. FIG. The timing chart which shows the operation|movement of a post-processing device when a 1st retraction member changes to a 3rd attitude|position. FIG. 2 is a block diagram illustrating a portion of the printing system related to media alignment. FIG. 4 is a correlation diagram showing the relationship between the medium surface condition of the medium and parameters. 5 is a flowchart showing the flow of determining the operation of the first retracting member and the second retracting member. 5 is a flowchart showing a subroutine for determining how the first retracting member and the second retracting member operate. FIG. 3 is a schematic diagram showing the force generated when the first drawing member draws the medium. FIG. 7 is a schematic diagram showing the force generated when the first drawing member aligns the medium with the rear end alignment part. FIG. 7 is a schematic diagram showing the force generated when the second drawing member draws the medium. FIG. 7 is a schematic diagram showing the force generated when the medium is discharged to the intermediate tray when the first drawing member is in the second posture. FIG. 7 is a schematic diagram showing the force generated when the medium is discharged to the intermediate tray when the first drawing member is in the third posture. An example of a control table for the required increase in rotational speed applied to the first drawing member and the second drawing member when the length of the medium in the conveying direction is 210 mm or less. An example of a control table for the required increase in rotational speed applied to the first drawing member and the second drawing member when the length of the medium in the conveyance direction exceeds 210 mm.

Hereinafter, a printing system including a transport device according to an embodiment will be described with reference to the drawings. A printing system includes, for example, a printing process in which ink, which is an example of a liquid, is ejected onto a medium such as paper to print characters or images on the medium, and a predetermined process, which is an example of processing, on the printed medium. Perform post-processing.

<Overview of printing system>
As shown in FIG. 1, the printing system 11 includes a printing device 13 that prints on a medium 50, and a post-processing device 200 that performs post-processing on the printed medium 50. The printing device 13 is, for example, an inkjet printer that prints characters and images by discharging ink onto the medium 50. The post-processing device 200 performs post-processing on the printed medium 50, such as a punching process for making holes in each medium 50 and a stapling process for binding a plurality of media 50 together.

The printing system 11 is provided with a conveyance path 17 shown by a two-dot chain line in FIG. 1 that extends from the printing device 13 to the post-processing device 200. Printing system 11 includes one or more transport roller pairs 19 that transport media 50 along transport path 17 as driven by transport motor 18 . The printing device 13 and the post-processing device 200 each include a conveyance motor 18 that drives a pair of conveyance rollers 19. The printing device 13 and the post-processing device 200 may each include a plurality of transport motors 18.

In the drawings, the printing system 11 is placed on a horizontal plane, and the direction of gravity is indicated by the Z axis, and the directions along the plane intersecting the Z axis are indicated by the X and Y axes. The X, Y, and Z axes are preferably perpendicular to each other, and the X and Y axes lie along a horizontal plane. In the following description, the X-axis direction is also referred to as the width direction X, and the Z-axis direction is also referred to as the vertical direction Z. The direction along the conveyance path 17 orthogonal to the width direction X is also referred to as the conveyance direction Y1. The conveyance direction Y1 is a direction in which the medium is conveyed along the conveyance path 17, and changes depending on the position on the conveyance path 17. Note that the transport direction of the portion of the transport direction Y1 where printing is performed on the medium 50 is parallel to the Y axis, and is also referred to as the transport direction Y.

<Overall configuration of printing system and flow of media processing>
First, the configuration of the printing device 13 and the flow of media processing will be explained.
As shown in FIG. 1, the printing device 13 is removably provided with a cassette 21 that can accommodate media 50 in a stacked state. The printing device 13 includes a pickup roller 22 that sends out the uppermost medium 50 among the media 50 housed in the cassette 21, and a separation roller 23 that separates the medium 50 sent out by the pickup roller 22 one by one.

In this embodiment, the printing device 13 includes one cassette 21, but may include a plurality of cassettes 21. That is, a plurality of cassettes 21 are stacked one on top of the other.

The printing device 13 includes a printing section 26 . The printing section 26 includes a support section 25 that is provided along the transport path 17 and supports the medium 50, and a liquid discharge section 27 that discharges liquid onto the medium 50 supported by the support section 25 to print. The liquid discharge section 27 is provided at a position facing the support section 25 with the transport path 17 interposed therebetween. The liquid ejection unit 27 may be a line head that can eject liquid simultaneously in the width direction X, or may be a serial head that ejects liquid while moving in the width direction X.

The printing device 13 includes, as part of the conveyance path 17, a discharge path 101 through which the medium 50 is discharged, a switchback path 102 through which the medium 50 is conveyed in a switchback manner, and a reversal path 103 through which the posture of the medium 50 is reversed. Be prepared. The medium 50 printed by the liquid discharge section 27 is discharged to the discharge section 104 through the discharge path 101 .

As shown in FIG. 1, when performing double-sided printing, a medium 50 printed on one side is conveyed to a switchback path 102, then conveyed in the opposite direction, and then conveyed from the switchback path 102 to a reversal path 103. Ru. The medium 50 that has been reversed in the reversal path 103 is again fed to the liquid ejecting section 27, and the liquid ejecting section 27 prints on the surface opposite to the surface that has already been printed. In this way, the printing device 13 performs double-sided printing on the medium 50.

The printing device 13 conveys the printed medium 50 toward the discharge section 104 or the post-processing device 200. That is, if post-processing is not instructed, the printing device 13 discharges the printed medium 50 to the ejection unit 104, and if post-processing is instructed, the printing device 13 transports the printed medium 50 toward the post-processing device 200. do. Note that the post-processing in this embodiment includes not only processing such as stapling processing that processes the medium 50, but also processing that does not perform processing on the medium 50, such as offset processing that shifts the medium 50 one copy at a time to the left and right.

<Configuration of post-processing device and flow of media processing>
Next, the configuration of the post-processing device 200 and the flow of media processing will be explained.
As shown in FIG. 1, the post-processing device 200 includes a carry-in section 207 that carries in the medium 50 that is carried out from the printing device 13, an intermediate tray 210 that performs post-processing on the medium 50 that has been carried in, and a post-processing unit 207 that carries in the medium 50 that is carried out from the printing device 13. and a discharge stacker 231 for loading the media 50.

The carry-in section 207 includes a receiving roller pair 201 that receives the medium 50, and a transport path that transports the medium 50 printed with the liquid discharged by the liquid discharging section 27 of the printing device 13 from the receiving roller pair 201 to the intermediate discharge roller pair 202. 17, and an acceptance sensor 203 that detects the rear end of the medium 50.

As shown in FIG. 1, the intermediate tray 210 on which the medium 50 conveyed by the conveyance path 17 is loaded has a first drawing member 211 on the intermediate tray 210 that pulls in the rear end of the medium 50 in a direction opposite to the conveyance direction Y1. and a second retracting member 212. The second retracting member 212 is provided downstream of the first retracting member 211 in the transport direction Y1. Further, the intermediate tray 210 includes a trailing edge alignment section 210a (see FIG. 2) that aligns the trailing edge of the medium 50, and a pair of side edge aligners that aligns a pair of side edges that are orthogonal to the trailing edge of the medium 50. member 215. Further, the intermediate tray 210 includes a post-processing mechanism 240 that performs post-processing on the aligned media 50, and a pair of ejection rollers 230 that ejects the post-processed media 50 from the intermediate tray 210.

As shown in FIG. 2, the post-processing device 200 includes a control section 250. The control unit 250 controls the operation of the first retraction member 211, the operation of the second retraction member 212, the operation of the side edge alignment member 215, the operation of the post-processing mechanism 240, and the operation of loading onto the discharge stacker 231. do.

As shown in FIG. 3, the medium 50 on which the first drawing member 211 performs the first drawing operation is the first medium 51, and when the first medium 51 is drawn in and performs the first drawing operation, the intermediate tray The medium 50 loaded on the top side of 210 is referred to as a second medium 52. The retracting operation of the first retracting member 211 is referred to as a first retracting operation.

The acceptance sensor 203 is arranged at a position slightly upstream of the pair of intermediate discharge rollers 202 in the transport direction Y1. The first medium 51 is conveyed by a pair of intermediate discharge rollers 202 . The surface on the intermediate tray 210 side when the medium 50 is loaded on the intermediate tray 210 is defined as the back surface, and the surface opposite to the back surface is defined as the front surface. The front surface of the medium 50 and the back surface of the medium 50 are combined to form a medium surface. When the rear end 51c of the first medium 51 passes the pair of intermediate discharge rollers 202, the first medium 51 falls onto the second medium 52.

When the first medium 51 falls, the medium dropping member 216 is rotated clockwise for a short time by the electric motor 235 (see FIG. 11), and then immediately rotated counterclockwise for a short time to return to its original state. By returning to the position, the medium drop member 216 accelerates the fall of the first medium 51.

Immediately after the first medium 51 falls onto the intermediate tray 210, the first drawing member 211 and the second drawing member 212 are stopped at an angle that does not make contact with the first medium 51. Hereinafter, this angle will be referred to as the "standby angle."

As shown in FIG. 4, after the second processing time Δ2 (see FIG. 9) has elapsed since the rear end 51c of the first medium 51 passes the acceptance sensor 203, the control unit 250 causes the rear end 51c of the first medium 51 to move above the intermediate tray 210. Control of the operation of the placed second retracting member 212 is started. That is, the second retracting member 212 starts rotating in the W2 direction and transports the first medium 51 in the direction of the trailing end alignment section 210a on the upstream side in the transport direction Y1.

As shown in FIG. 5, the intermediate tray 210 is arranged in an inclined posture such that the upstream end is located below the vertical direction Z than the downstream end in the conveying direction Y1. A force is applied to the fallen first medium 51 in the direction of sliding down the upper surface of the intermediate tray 210 toward the upstream side in the transport direction Y1 due to gravity. The second drawing member 212 rotates in the W2 direction and draws the first medium 51 upstream in the transport direction Y1. The retracting operation of the second retracting member 212 is referred to as a second retracting operation.

As shown in FIG. 6, when the rear end 51c of the first medium 51 reaches the first drawing member 211, the control unit 250 controls the first drawing member 211, which is disposed on the upstream side in the transport direction Y1 and above the intermediate tray 210. Control of the first retracting operation of the member 211 is started. The time when the rear end of the medium 50 reaches is just before the rear end of the medium 50 hits the first retracting member 211, and when the first retracting member 211 is changed to the height of the first posture and starts rotating, the rear end of the medium 50 This is the timing when the first blade A211a does not hit the first blade C211c of the first drawing member 211 and the first blade A211a pulls in the surface 51a of the first medium 51 (see FIG. 5). The first medium 51 is drawn upstream in the transport direction Y1 by this first drawing operation. That is, after the rear end 51c of the first medium 51 passes through the transport path 17, the first drawing member 211 pulls it upstream in the transport direction Y1 in the first attitude by the first rotary motor 213 (see FIG. 11). The first retracting operation is started.

The first posture is a posture in which the first drawing member 211 rotates in the W1 direction at a predetermined height and draws the rear end 51c of the first medium 51 into the rear end alignment section 210a. The height of the first drawing member 211 is the distance between the loading bottom surface 210b of the intermediate tray 210 and the first rotation center 211e of the first drawing member 211 (see FIG. 15). The predetermined height is a height suitable for pulling in the type of media 50 recommended for use in the printing device 13 by the user. The control unit 250 causes the first vertical movement motor 253 (see FIG. 11) to adjust the first rotation center 211e (see FIG. 15) of the first retraction member 211 when the first retraction member 211 is in the first orientation. Height can be changed.

As shown in FIG. 7, the first drawing member 211 rotates in the W1 direction and generates a force that draws the first medium 51, thereby moving the rear end 51c of the first medium 51 to the rear end alignment part 210a. reach it. The first drawing member 211 abuts the entire side of the rear end 51c of the first medium 51 against the reference surface, which is the rear end alignment portion 210a, to the extent that the rear end 51c of the first medium 51 is not buckled. The rear end alignment part 210a contacts the rear end 51c of the first medium 51 drawn in by the first drawing member 211, and aligns the rear end 51c of the first medium 51.

The second integrated number of rotations after the second drawing member 212 starts the second drawing operation is the number of rotations required to align the rear end 51c of the first medium 51 with the rear end alignment part 210a. 2 Reach the required rotation speed. At that time, the control unit 250 is configured to regulate the second retracting operation.

When the alignment of the side edges of the first medium 51 and the rear edge of the first medium 51 are completed, the first cumulative number of rotations after the first drawing member 211 starts the first drawing operation is The first required number of rotations required to align the rear end 51c of the first medium 51 with the rear end alignment portion 210a is reached. At that time, the control unit 250 is configured to regulate the first retracting operation.

The first retracting member 211 and the second retracting member 212 rotate by the first required number of rotations and the second required number of rotations, respectively, to ensure that the rear end 51c of the first medium 51 hits the rear end alignment part 210a. It can be matched by matching. Therefore, when the first cumulative rotation speed and the second cumulative rotation speed, which are the cumulative rotation speeds of the first retraction member 211 and the second retraction member 212, reach the first required rotation speed and the second required rotation speed, It can be determined that the rear end 51c of the No. 1 medium 51 has reached the rear end alignment section 210a. The first required rotation speed and the second required rotation speed can be changed depending on the state of the medium. The above is the alignment and loading operation of the medium 50.

Next, post-processing will be explained. As shown in FIG. 8, the media 50 that have passed through the pair of intermediate discharge rollers 202 are stacked one after another on the intermediate tray 210. When the number of media 50 designated by the user is stacked on the intermediate tray 210, the post-processing mechanism 240 performs post-processing on the bundle of the stacked media 50. For example, the stack of media 50 is stapled at the binding position specified by the user. The bundle of media 50 that has been subjected to post-processing is discharged by a pair of discharge rollers 230 onto a discharge stacker 231 that is disposed so as to be movable up and down along the outer surface of the post-processing device 200 .

Stacks of post-processed media 50 are stacked one after another on intermediate tray 210 . Note that the post-processing device 200 can also perform an offset process or the like in which the bundle of media 50 is shifted one part at a time in the width direction X onto the ejection stacker 231 and ejected.

<Movement of each part of the post-processing device>
Next, referring to the timing chart shown in FIG. 9, when the attitude of the first retracting member 211 changes from the first attitude to the second attitude, the plurality of media 50 are aligned and stacked on the intermediate tray 210. The movements of each part of the post-processing device 200 at this time will be explained. Times t2 to t8 shown in FIG. 9 indicate states corresponding to FIGS. 2 to 8, respectively.

When the post-processing operation is started, the transport motor 208 begins to rotate and is ready to receive the medium 50. After transporting the final media for a print job, it stops rotating. Further, each time the output of the receiving sensor 203 is turned off, the transport motor 208 temporarily slows down its rotational speed. That is, each time the rear end of the medium 50 passes the pair of intermediate discharge rollers 202, the conveyance motor 208 reduces the conveyance speed of the medium 50, thereby preventing the medium 50 from flying far from the pair of intermediate discharge rollers 202.

The receiving sensor 203 detects the presence or absence of the medium 50, and when the medium 50 passes through the detection target position, the output is turned ON, and when the medium does not pass, the output is turned OFF. Note that even if the output of the acceptance sensor 203 is turned off, the rotational speed of the transport motor 208 may be maintained.

The second rotation motor 214 rotates the second retraction member 212 . When the second processing time Δ2 has elapsed from the timing at which the output of the acceptance sensor 203 changes from ON to OFF, the second rotary motor 214 is turned ON. That is, the second retracting member 212 starts rotating. After the second rotary motor 214 is turned on and rotates for a second rotation time N2, the second rotary motor 214 is turned off and the second retracting member 212 stops rotating. That is,
The control unit 250 causes the second cumulative number of rotations after starting the second retraction operation to reach a second required number of rotations necessary to align the rear end of the first medium 51 with the rear end alignment portion 210a. When this occurs, the second retracting operation is restricted.

The first vertical movement motor 253 changes the height of the first retracting member 211. It is possible to switch between the height of the first posture, which is a posture in which the medium 50 is pulled in, the height of the second posture, which is a posture in which the medium 50 is held, and the height of the third posture, which is a posture in which the medium 50 is separated. Further, the first vertical movement motor 253 can change the height of the first posture. FIG. 9 shows a state in which the attitude of the first retracting member 211 is changing between a first attitude and a second attitude.

The first rotation motor 213 rotates the first retraction member 211 . When the first processing time Δ1 has elapsed from the timing at which the output of the acceptance sensor 203 changes from ON to OFF, the first rotary motor 213 is turned ON. That is, the first retracting member 211 starts rotating.

The side edge alignment motor 256 is turned on for a short time when the rear end of the medium 50 reaches the rear edge alignment part 210a, and performs side edge alignment operation of the medium 50. Thereafter, when the movement of the medium 50 becomes stable, the alignment operation of the rear end and side ends of the medium 50 is completed, and the first rotary motor 213 is turned off. That is, the first rotary motor 213 rotates for a first rotation time N1 from the start of rotation and then stops rotating, thereby causing the first retracting member 211 to stop rotating. At the same time, the first vertical movement motor 253 changes the height of the first retracting member 211 from the height of the first attitude to the height of the second attitude. That is, when the first cumulative number of rotations reaches the first required number of rotations, the control unit 250 performs the first drawing operation of the first drawing member 211 while the first drawing member 211 is in contact with the first medium 51. stop. Then, the control unit 250 lowers the height of the first drawing member 211 and changes it to the second posture in which the first medium 51 is pressed down by the first drawing member 211.

When the following medium 50 is discharged onto the intermediate tray 210 by the first vertical movement motor 253 when the height of the first retracting member 211 is at the height of the second posture, the second rotation motor 214 is turned ON. , and the second retracting member 212 starts rotating. That is, when the first drawing member 211 is in the second attitude, the control unit 250 causes the second drawing member 212 to start the second drawing operation of drawing the first medium 51 upstream in the transport direction Y1.

When the rear end of the following medium 50 reaches the first drawing member 211, the first vertical movement motor 253 changes the height of the first drawing member 211 from the height of the second attitude to the height of the first attitude. Then, the first rotation motor 213 rotates the first retraction member 211 again. That is, when the rear end 51c of the first medium 51 reaches the first drawing member 211, the control unit 250 returns the first drawing member 211 from the second attitude to the first attitude and restarts the first drawing operation. It is configured to allow Note that the control unit 250 returns the first drawing member 211 from the second attitude to the first attitude and restarts the first drawing operation until the rear end 51c of the first medium 51 reaches the first drawing member 211. It may be configured to do so.

The nip motor 229 is turned ON from when the media bundle is stapled by the post-processing mechanism 240 until the media bundle is ejected to the ejection stacker 231, and the ejection roller pair 230 rotates the media bundle from above and below. Nip.

The ejection motor 232 is turned on at the same time as the stapling process ends, and the media bundle is ejected to the ejection stacker 231.
Next, with reference to the timing chart shown in FIG. 10, the movement of each part of the post-processing device 200 will be described when the attitude of the first retracting member 211 changes from the first attitude to the third attitude. Times t2 to t8 shown in FIG. 10 indicate states corresponding to FIGS. 2 to 8, respectively. Note that the description of parts that overlap with those in FIG. 9 will be omitted. FIG. 10 shows a configuration in which the attitude of the first retracting member 211 changes between a first attitude and a third attitude.

When the movement of the medium 50 becomes stable after the side edge alignment operation of the medium 50, the first vertical movement motor 253 changes the height of the first retracting member 211 from the height of the first attitude to the height of the third attitude. do. That is, when the first cumulative number of rotations reaches the first required number of rotations, the control unit 250 increases the height of the first retraction member 211 and moves the first retraction member 211 from the first attitude to the first medium. 51 to a third attitude away from the object. In this manner, the first drawing member 211 assumes the third attitude when it completes drawing the first medium 51, thereby preventing excessive drawing of the medium 50.

When the following medium 50 is detected by the first vertical movement motor 253 when the height of the first retraction member 211 is at the height of the third posture, the second rotation motor 214 is turned ON, and the second retracting member 212 starts rotating. That is, the control unit 250 causes the second drawing member 212 to start a second drawing operation to draw the first medium 51 upstream in the transport direction Y1 when the first drawing member 211 is in the third attitude.

The first vertical movement motor 253 changes the height of the first retracting member 211 from the height of the third posture to the height of the first posture, and the first rotation motor 213 rotates the first retracting member 211 again. . That is, the control unit 250 causes the first drawing member 211 to return from the third attitude to the first attitude and restart the first drawing operation when the rear end 51c of the first medium 51 reaches the first drawing member 211. is configured to do so. Note that the control unit 250 causes the first drawing member 211 to return from the third attitude to the first attitude and restart the first drawing operation until the rear end 51c of the first medium 51 reaches the first drawing member 211. It may be configured to do so.

<Block diagram regarding media alignment of printing system>
As shown in FIG. 11, the printing system 11 includes a printing device 13 and a post-processing device 200.

The printing device 13 is controlled by a printing device control section 60. The printing device 13 includes a printing device control section 60 , a transmission section 65 , a printing section 26 , a transport section 64 , an operation section 62 , and an environment sensor 61 . The printing device 13 may have other elements depending on the function of the printing device 13, but in FIG. 11, elements that are not related to alignment of the medium 50 in the post-processing device 200 are omitted.

As shown in FIG. 11, the transmitter 65 is connected to an external network NW, and receives a print command from a server, computer, etc. connected to the network NW. The print command includes the size of the medium 50, the basis weight of the medium 50, the number of pages to be printed, the print data for each page, the designation of single-sided printing or double-sided printing, the number of copies to be printed, the type of post-processing, and the type of post-processing to be performed. Contains other necessary printing information.

In the print information, when the medium 50 of the size and basis weight specified by the server, computer, etc. is stored in the cassette 21 of the printing device 13 (see FIG. 1), the transmitter 65 transmits the print command. accept. The transmitter 65 notifies the printing device controller 60 of the print information. The printing device control section 60 controls the operations of the printing section 26 and the conveyance section 64 to perform printing in accordance with the print command received by the printing device control section 60 from the transmission section 65.

As shown in FIG. 11, the environmental sensor 61 measures the temperature and humidity at the location where the environmental sensor 61 is installed, and notifies the printing device control unit 60 of the measured temperature and humidity. The purpose of the environmental sensor 61 is to measure the temperature and humidity of the environment of the medium 50 being printed. Therefore, the environmental sensor 61 is installed near the printing section 26.

The operation unit 62 is, for example, a touch panel that also serves as a liquid crystal display. Even if the printing system 11 does not receive a print command through the network NW, the printing system 11 can print in response to a print command from the operation unit 62.

In this embodiment, the printing system 11 has a test mode in which a test pattern is printed to measure the alignment accuracy of the trailing edge of the post-processed medium 50. The printing device control unit 60 stores test pattern data for measuring the alignment accuracy of the trailing edge of the post-processed medium 50 in its internal memory. The printing system 11 is configured to be able to perform a test process of printing a test pattern.

As shown in FIG. 11, the post-processing device 200 is controlled by a control section 250. The post-processing device 200 includes a post-processing mechanism 240. The operation of the post-processing mechanism 240 is controlled by a control section 250. The control unit 250 determines the first required number of revolutions of the first retracting member 211, the height of the first retracting member 211, and the first required number of revolutions of the first retracting member 211 when the first required number of revolutions is reached, according to the result of the test process. The configuration is such that the posture of the second retracting member 212 and the second required number of rotations of the second retracting member 212 can be changed.

For example, a service person for the printing system 11 can change these items by inputting them from the operation unit 62 according to the results of the test process. For example, the printing duty of the liquid ejected onto the medium 50 by the liquid ejecting unit 27, the waiting time after printing, the basis weight and size, and when the first drawing member 211 performs the first drawing operation of the medium 50 onto the intermediate tray 210. The configuration is such that different numerical values can be input depending on the number of media loaded on the machine and the combination thereof. The printing duty of the liquid ejected onto the medium 50 by the liquid ejecting section 27 is also simply referred to as printing duty.

Here, the printing duty refers to the amount of liquid ejected per area of the medium 50. Print duty is indicated from 0 to 100%. In this embodiment, the liquid ejecting unit 27 performs printing with three types of dot sizes, for example, large, medium, and small. The amount of liquid ejected per area of the medium 50 during solid printing in which large dot droplets, which are the maximum dot size, are ejected using all nozzles is defined as a printing duty of 100%. In other words, the printing duty is a parameter that sets the amount of liquid ejected per area during solid printing to 100%. Furthermore, if the dot size of the liquid ejected using all the nozzles of the liquid ejecting section 27 is the same, the print duty increases as the print resolution increases. Note that the liquid ejecting section 27 may be configured to eject liquid of one type of dot size.

As shown in FIG. 11, the printing device control unit 60 of the printing device 13 and the control unit 250 of the post-processing device 200 exchange information with each other. When the medium 50 is conveyed from the printing device 13 to the post-processing device 200, the printing device control unit 60 informs the control unit 250 of the size of the medium 50 to be conveyed and the basis weight of the medium 50. Notice. When the medium 50 is the final medium in units of copies, a signal indicating that it is the final medium in units of copies and the type of post-processing in units of copies are notified.

For example, when 10 media 50 are subjected to stapling processing and discharged to the discharge stacker 231, the printing device control unit 60 informs the control unit 250 that the first to ninth media will be transported from now on. The size of the medium 50 and the basis weight of the medium 50 are notified. For the 10th sheet, in addition to the size of the medium 50 to be transported and the basis weight of the medium 50, a signal indicating that it is the final medium in units of copies and that the post-processing is stapling processing is sent. Notice. Therefore, the ten media 50 are subjected to stapling processing and are discharged to the discharge stacker 231. Then, the control unit 250 notifies the printing device control unit 60 that all processing has been completed normally. The transmitting unit 65 notifies the server, computer, etc. that received the printing instruction via the network NW that printing and post-processing have been completed normally.

As shown in FIG. 11, in the present embodiment, the control unit 250 of the post-processing device 200 uses information about the printing duty of the medium 50 and information about the printing time of the medium 50 to influence the medium surface state of the medium 50. The water content information is acquired from the printing device control unit 60 of the printing device 13. Furthermore, the control unit 250 controls the temperature of the environment in which the printing device 13 is installed, which is obtained by the environmental sensor 61, and the humidity in the environment in which the printing device 13 is installed, to adjust the moisture content that affects the medium surface condition of the medium 50. The information is acquired from the printing device control unit 60 of the printing device 13. The medium surface condition includes not only the moisture content but also waving, partial deformation, and curling of the medium 50 caused by moisture content or partial moisture content.

The information regarding the printing time of the medium 50 includes the printing time on the medium 50 printed with the liquid ejected by the liquid ejecting unit 27, the waiting time after printing on the medium 50 printed with the liquid ejected by the liquid ejecting unit 27, including. The information regarding the printing time of the medium 50 may include the transport time within the printing apparatus of the medium 50 printed with the liquid ejected by the liquid ejecting section 27. Information regarding the printing time of the medium 50 includes both information regarding the front side of the medium 50 and information regarding the back side.

In the following description, the printing time on the medium 50 printed with the liquid ejected by the liquid ejecting section 27 is "printing time", and the waiting time after printing on the medium 50 printed with the liquid ejected by the liquid ejecting section 27 is "printing time". "Waiting time".

The standby time is the time during which the medium 50 is kept on standby within the printing device 13 when the printing duty is large. This is set in order to prevent the medium 50 from having a very high moisture content when the basis weight of the medium 50 is small and the printing duty is large, and the medium 50 cannot be normally conveyed along the conveyance path 17. By setting this waiting time, the moisture content of the medium 50 is reduced, and the medium 50 can be transported.

The waiting time is a time period in which the medium 50 waits after printing according to the print duty, and is a time for reducing the moisture content of the medium 50 until it becomes possible to convey the medium 50. The rate remains almost unchanged. However, the higher the printing duty, the longer the waiting time. Therefore, due to shrinkage of the medium surface during the drying process of the medium 50 during the standby time, the longer the standby time is, the worse the medium surface condition becomes. In other words, the waiting time does not affect the improvement of the medium surface condition.

The print duty includes a front duty, which is the duty of the liquid discharged onto the front surface of the medium 50 transported by the transport path 17, and a back surface duty, which is the duty of the liquid discharged onto the back surface of the medium 50, which was transported by the transport path 17. There is a duty.

Further, the printing duty in the area on the surface of the medium 50 where the first drawing member 211 contacts the medium 50 or the area overlapping the contact area is referred to as the contact portion surface duty. The printing duty in a region on the back surface of the medium 50 that overlaps with the region where the first drawing member 211 contacts the medium 50 is referred to as a contact portion back surface duty. The contact portion surface duty and the contact portion back surface duty are collectively referred to as the contact portion duty.

As shown in FIG. 11, in this embodiment, when the medium 50 is conveyed from the printing device 13 to the post-processing device 200, the printing device control unit 60 instructs the control unit 250 to determine the surface duty, The back surface duty, the contact section surface duty, and the contact section back surface duty are notified.

Both the contact portion surface duty and the contact portion back surface duty do not have to be in exactly the same area as the area where the first drawing member 211 contacts the medium 50 or the area that overlaps with the contact area. It may be a region that includes a region where the first drawing member 211 contacts the medium 50 or a region that overlaps with the contact region. For example, the medium 50 may be divided into three parts in the transport direction Y1, and the region may be one third of the medium 50 on the rear end side of the medium 50. Alternatively, for example, the width direction X of the medium 50 may be divided into three or more regions, and two of these regions may be in contact with the first drawing member 211. The area where the first drawing member 211 contacts the medium 50 or the area that overlaps with the contact area does not need to be included, but may be a nearby area.

The transportation time after printing on the medium 50 printed with the liquid ejected by the liquid ejecting section 27 is calculated by the control section 250 based on the job details notified by the printing device control section 60 . The time during which the medium 50 is conveyed through the conveyance path 17 of the printing device 13 is determined by the control unit using the conveyance speed of the medium 50 in the conveyance path 17 of the printing device 13 and the conveyance distance of the conveyance path 17 of the printing device 13. 250. The time during which the medium 50 is transported through the transport path 17 of the post-processing device 200 is calculated using the transport speed of the medium 50 in the transport path 17 of the post-processing device 200 and the transport distance of the transport path 17 of the post-processing device 200. , calculated by the control unit 250. The printing device control unit 60 calculates the time during which the medium 50 is transported through the transport path 17 of the printing device 13 and notifies the control unit 250. The time for transportation may be calculated.

The control unit 250 controls the liquid ejection unit 27 to eject by adding the time during which the medium 50 is conveyed through the conveyance path 17 of the printing device 13 and the time during which the medium 50 is conveyed through the conveyance path 17 of the post-processing device 200. The transportation time after printing on the medium 50 printed with the liquid is calculated. Hereinafter, the transportation time after printing on the medium 50 printed with the liquid discharged by the liquid discharge unit 27 will be referred to as "transportation time after printing."

The control unit 250 uses the conveyance pitch time of the medium 50 from the start of the first pull-in operation to the start of the next first pull-in operation for calculation. Hereinafter, the time from starting the first retracting operation to starting the next first retracting operation will be referred to as "conveyance pitch time." The control unit 250 calculates the elapsed time from when the first medium 51 is printed with the liquid discharged by the liquid discharge unit 27 until the first pull-in member 211 starts the first pull-in operation. Hereinafter, the time from when the first medium 51 is printed with the liquid ejected by the liquid ejecting section 27 until the first drawing member 211 starts the first drawing operation will be referred to as "elapsed time." The elapsed time may be determined by using at least one of the printing time, the post-printing transport time, and the transport pitch time.

The control unit 250 may determine the elapsed time by using only the time that has a large effect on improving the medium surface condition among the times that constitute the elapsed time. For example, if the transportation time is very long and the transportation time after printing is dominant over the elapsed time, the control unit 250 may use only the transportation time after printing as the elapsed time. That is, if the transportation time after printing is dominant in improving the medium surface condition, the control unit 250 may use only the transportation time after printing as the elapsed time.

In this embodiment, the control unit 250 calculates the elapsed time on the back side of the first medium 51 and the elapsed time on the front side of the second medium 52. In the case of double-sided printing, the elapsed time differs between the front and back sides of the medium 50. In the case of this embodiment, in the case of double-sided printing, the side of the medium 50 that is printed first becomes the back side, and the side of the medium 50 that is printed later becomes the front side. That is, the elapsed time on the back side is longer than the elapsed time on the front side. Hereinafter, the elapsed time on the front side will be distinguished from the "front elapsed time" and the elapsed time on the back side will be referred to as the "back side elapsed time."

The elapsed time on the back side of the first medium 51 is calculated from the printing time on the back side, the waiting time on the back side, the printing time on the front side, the waiting time on the front side, and the transportation time after printing. The surface elapsed time of the second medium 52 is calculated from the printing time on the front surface, the waiting time on the front surface, the transportation time after printing, and the transportation pitch time.

The elapsed time is also affected by the print duty. For example, when comparing when the printing duty is large and when the printing duty is small, the printing time and standby time are shorter when the printing duty is small. That is, when the print duty is small, the elapsed time is short.

<Relationship between media surface condition and parameters>
As shown in FIG. 12, the medium surface state of the back surface 51b of the first medium 51, the medium surface state of the front surface 52a of the second medium 52, and the medium surface state of the surface 52a of the second medium 52 at the start of the first drawing operation, and The water content state of the medium 50 including the medium 52 of No. 2 is influenced by a plurality of parameters.

The water content state of the surface of the medium 50 immediately after printing is mainly determined by the printing duty of the surface of the medium 50 and the basis weight of the medium 50. When the basis weight of the medium 50 is small and the printing duty of the medium 50 is large, the moisture content becomes large and the waviness and curling become large.

The moisture content state of the back surface of the medium 50 immediately after printing is mainly determined by the printing duty of the back surface of the medium 50 and the basis weight of the medium 50. When the basis weight of the medium 50 is small and the printing duty on the back side of the medium 50 is large, the moisture content becomes high and the waviness and curling become large.

As shown in FIG. 12, the medium surface condition of the back surface of the first medium 51 at the start of the first pull-in operation is the medium surface condition of the back surface of the medium 50 immediately after printing, and the elapsed time since the medium 50 was printed. It is influenced by the size of the medium 50, the temperature of the environment in which the printing device 13 is installed, and the humidity of the environment in which the printing device 13 is installed. Hereinafter, the temperature of the environment in which the printing device is installed will be referred to as "environmental temperature," and the humidity in the environment in which the printing device is installed will be referred to as "environmental humidity."

When the medium surface condition of the back surface of the medium 50 immediately after printing is poor, the medium surface condition of the back surface 51b of the first medium 51 at the start of the first pull-in operation becomes poor. A poor medium surface condition means that the moisture content is high and there are large waves and curls.

When a long time has passed since printing, the drying time becomes longer and the moisture content decreases. However, in most cases where the elapsed time is long, printing with a high printing duty is performed and the waiting time becomes long. Therefore, even if the medium has a decreased moisture content due to a long elapsed time, the moisture content of the medium whose elapsed time is longer than a certain level is the upper limit of the moisture content that can be conveyed by the conveyance path 17.

The way the medium surface changes differs depending on the type of medium. The type of the medium 50 includes the material and components of the medium 50, the size of the medium 50, the grain direction if the medium 50 is paper, the basis weight of the medium 50, and the like.

When the environmental humidity is high, the medium 50 is more difficult to dry than when the environmental humidity is low, and the medium surface condition becomes worse. Furthermore, when the environmental temperature is low, the medium 50 is more difficult to dry than when the environmental temperature is high, and the medium surface condition becomes worse. However, the influence of environmental temperature is smaller than the influence of environmental humidity.

As shown in FIG. 12, the medium surface state of the surface 52a of the second medium 52 at the start of the first pulling operation is determined by the moisture content state of the surface of the medium 50 immediately after printing and the elapsed time since the medium 50 was printed. , the size of the medium 50, the environmental temperature, and the environmental humidity. That is, the front surface of the second medium 52 is affected by the same parameters as the back surface of the first medium 51.

As shown in FIG. 12, the hydration state of the medium 50 loaded so far at the start of the first retraction operation is the hydration state of the front surface of the medium 50 immediately after printing, the hydration state of the back surface of the medium 50 immediately after printing, It is affected by the elapsed time of each medium 50 since printing, the size of the medium 50, the number of sheets of the medium 50 loaded, the environmental temperature, and the environmental humidity.

Regarding the surface condition of the media 50 loaded up to that point at the start of the first retraction operation, the longer the elapsed time for each medium 50 since printing, the longer the drying time and the better the moisture content. It does not have as much influence as the first medium 51 or the second medium 52.

When the size of the medium 50 is large, the moisture content of the medium 50 loaded on the intermediate tray 210 is difficult to decrease. The loaded medium 50 begins to dry from the part that is exposed to the air. The areas exposed to air are the surface 52a of the second medium 52 loaded on top and the four sides of all the loaded media 50. That is, the leading edge, the trailing edge, and the two side edges.

When the size of the medium 50 is large, the distance from the center to the four sides of the medium 50 is long, so it takes a long time for the medium 50 to dry, and the moisture content of the loaded medium 50 is difficult to decrease. That is, when the size of the medium 50 is large, the difference in moisture content between the center and the ends of the medium 50 loaded on the intermediate tray 210 becomes large, so that waving tends to occur more easily. The larger the number of loaded media 50, the greater the effect. The ease with which waviness occurs varies depending on the type of medium 50.

Regarding the moisture content of the medium 50 loaded up to that point at the start of the first drawing operation, when the environmental humidity is high, the medium 50 is more difficult to dry than when the environmental humidity is low, and the moisture content becomes worse. Furthermore, when the environmental temperature is low, the medium 50 is more difficult to dry than when the environmental temperature is high, and the water content becomes worse. However, the influence of environmental temperature is smaller than the influence of environmental humidity.

That is, all of the front duty, the back duty, the front elapsed time, the back elapsed time, the environmental temperature, the environmental humidity, the size of the medium 50, and the basis weight of the medium 50 are determined by the first drawing operation. Parameters of the water content state of the medium 50 at the start. Hereinafter, the printing duties on the first medium 51 will be referred to as "first front duty" and "first back duty". Similarly, the printing duties on the second medium 52 are referred to as "second front duty" and "second back duty".

In FIG. 12, the same relationship is shown even if the "surface of the medium" is replaced with "the surface of the medium, where the first drawing member 211 contacts the medium or overlaps the contact area." Furthermore, the same relationship is shown even if the "back surface of the medium" is replaced with "the back surface of the medium and the region that overlaps with the region where the first drawing member 211 contacts the medium." That is, both the contact portion surface duty and the contact portion back surface duty of each medium 50 are parameters of the water content state of the medium 50 at the start of the first drawing operation.

Hereinafter, the area where the first drawing member 211 contacts the medium 50 or the area that overlaps with the contact area will be referred to as "first contact part surface duty" and "first contact part back surface duty." Similarly, a region overlapping with a region where the second drawing member 212 contacts the medium 50 is referred to as a "second contact portion surface duty" and a "second contact portion back surface duty." The same applies to the printing duty of the medium 50 stacked below the second medium 52.

Note that the height of the medium 50 loaded on the intermediate tray 210 is defined according to the basis weight of the medium 50 and the number of sheets loaded, and the respective distances from the center of the drawing members 211 and 212 to the surface of the first medium 51 are determined. change. These distances vary the strength of the force with which the retraction members 211, 212 push the surface of the first medium 51 in the vertical direction during the retraction operation. The frictional force that the first medium 51 receives when sliding the first medium 51 on the surface of the second medium 52 is the drag force that the first medium 51 receives from the surface of the second medium 52, and the frictional force that the first medium 51 receives from the surface of the second medium 52. It is given by the product of the friction coefficient of the first medium 51 with respect to the medium 52. This drag force increases as the force with which the drawing members 211 and 212 push the surface of the first medium 51 becomes stronger. From this point of view, the basis weight and the number of sheets loaded on the medium 50, which influence the drag force, can be parameters that determine the operation of the drawing members 211 and 212, independently of the parameter that determines the water content state of the medium 50, which influences the coefficient of friction.

<Method of determining the operation of the first retracting member and the second retracting member>
In the post-processing device 200, the control unit 250 controls the operations of the first drawing member 211 and the second drawing member 212, so that the medium 50 is aligned on the intermediate tray 210. A flow in which the control unit 250 determines the operations of the first retracting member 211 and the second retracting member 212 will be described with reference to the flowchart shown in FIG. 13. FIG. 13 shows a case where the number of copies to be printed is one.

As shown in FIG. 13, in step S501, the printing device control unit 60 obtains the configuration of a print job based on a print command. The configuration of the print job includes the size of the medium 50 to be used, the basis weight of the medium 50 to be used, the number of pages to be printed, the print data for each page, the designation of single-sided printing or double-sided printing, the number of copies to be printed, and post-processing. Includes types of.

In step S502, the printing device control unit 60 determines the front surface duty of each medium 50, the back surface duty of each medium 50, the contact portion surface duty of each medium 50, and the contact portion back surface of each medium 50 from the print data for each page. Calculate the duty. For example, if the print job is double-sided printing of 100 pages, four types of duties are calculated for the 50 sheets of media 50 that constitute the output product.

In step S503, the printing device control unit 60 obtains the environmental temperature and environmental humidity from the environmental sensor 61. The printing device control unit 60 notifies the control unit 250 of the post-processing device 200 of the environmental temperature and environmental humidity along with a post-processing preparation command.

In step S504, the post-processing device 200 performs an initial operation to complete preparations for receiving the medium 50 and performing post-processing.
In step S505, the printing device control unit 60 receives a notification from the control unit 250 of the post-processing device 200 that the initial operation of the post-processing device 200 has been completed. Printing device 13 starts a print job.

In step S506, the printing device control unit 60 determines whether the medium 50 to be sent to the post-processing device 200 after printing is the final medium in units of copies or not the final medium in units of copies. This is because the content that the printing device control unit 60 notifies the control unit 250 is different depending on whether the final medium is in units of copies or the final medium is not in units of copies.

When the medium 50 to be sent to the post-processing device 200 is the final medium in units of copies, YES is determined in step S506, and the printing device control unit 60 moves the process to step S507. If the medium 50 to be sent to the post-processing device 200 is not the final medium in units of copies, the result in step S506 is NO, and the printing device control unit 60 moves the process to step S508. Even if the medium 50 sent to the post-processing device 200 is the first medium 50 of the print job, it is the final medium in units of copies when only one sheet is printed. Generally, when printing only one sheet, the output unit 104 of the printing device 13 is selected as the output destination, and when the post-processing device 200 is selected as the output destination, the copy unit is composed of multiple copies. . Therefore, when sending the first medium 50 to the post-processing device 200, the answer in step S506 is NO, and the printing device control unit 60 moves the process to step S508.

In step S508, when the printing device control unit 60 sends out the medium 50 to the post-processing device, it determines the size of the medium 50, the basis weight of the medium 50, the front surface duty, the back surface duty, the contact section surface duty, and the contact section. The control unit 250 is notified of the back side duty and information regarding printing time. Generally, in most cases, the size and basis weight of the media 50 are the same in units of copies. In rare cases, several A3 size media may be included in a copy unit of A4 size media. Furthermore, in rare cases when stapling is performed in units of copies, the user may designate only two sheets, the front cover and the back cover, as media with a large basis weight.

Then, in step S509, a subroutine shown in FIG. 14 for determining the operating method of the first retracting member 211 and the second retracting member 212 is executed.
In step S511, the post-processing device 200 starts aligning the medium 50 using the operation method determined in step S509. When the alignment operation starts, the process returns to step S506 and shifts to processing of the second medium 50. When the medium 50 to be sent to the post-processing device 200 is the final medium in units of copies, YES is determined in step S506, and the printing device control unit 60 moves the process to step S507.

In step S507, when the printing device control unit 60 sends out the medium 50 to the post-processing device, in step S508, the printing device control unit 60 sends final medium information and post-processing information in addition to the information notified to the control unit 250. The type of information is notified to the control unit 250.

Then, in step S509, a subroutine shown in FIG. 14 for determining the operating method of the first retracting member 211 and the second retracting member 212 is executed.
In step S510, the post-processing device 200 performs an alignment operation, a post-processing operation, and an ejecting operation of the medium 50 according to the operation method determined in step S509. Upon acquiring the type of post-processing, the control unit 250 performs the specified post-processing before the bundle of media 50 stacked on the intermediate tray 210 is ejected to the ejection stacker. For example, stapling processing is performed on a bundle of media 50 stacked on the intermediate tray 210 at a designated position. When the control unit 250 acquires the final medium information, it determines that the medium 50 is the final medium in units of copies, and discharges the bundle of media 50 stacked on the intermediate tray 210 to the discharge stacker 231. The printing device control unit 60 and the control unit 250 of the post-processing device 200 end the processing.

Next, a subroutine for determining the operating method of the first retracting member 211 and the second retracting member 212 will be described with reference to the flowchart shown in FIG. Note that the following is an example of double-sided printing.

As shown in FIG. 14, in step S601, the control unit 250 calculates the elapsed time from printing to the pull-in operation from the information regarding the printing time acquired from the printing device control unit 60. In this embodiment, the control unit 250 calculates the back side elapsed time of the first medium 51 and the front side elapsed time of the second medium 52.

In step S602, the control unit 250 estimates the medium surface state of the back surface 51b of the first medium 51 based on a plurality of conditions. The plurality of conditions are the size of the medium 50, the basis weight of the medium 50, the back surface duty, the contact portion back surface duty, and the back surface elapsed time. As shown in FIG. 12, the medium surface state of the back surface 51b of the first medium 51 changes depending on these multiple conditions.

In step S603, the control unit 250 similarly estimates the medium surface state of the surface 52a of the second medium 52 based on a plurality of conditions. The plurality of conditions are the size of the medium 50, the basis weight of the medium 50, the surface duty, the contact portion surface duty, and the surface elapsed time. As shown in FIG. 12, the medium surface state of the surface 52a of the second medium 52 changes depending on these multiple conditions.

In step S604, the control unit 250 counts the number of media 50 conveyed from the printing device 13 to determine the number of sheets stacked on the intermediate tray 210 when the first retraction member 211 starts the first retraction operation. Calculate.

In step S605, the control unit 250 estimates the height of the medium 50 stacked on the intermediate tray 210 based on a plurality of conditions. The multiple conditions include the size of each medium 50 loaded on the intermediate tray 210, the basis weight of each medium 50, the front surface duty of each medium 50, the back surface duty of each medium 50, and the surface of each medium 50. These are the elapsed time, the elapsed time on the back side of each medium 50, and the number of sheets loaded on the intermediate tray 210.

As shown in FIG. 12, the water content state of the medium 50 loaded on the intermediate tray 210 changes depending on these multiple conditions. All of these conditions may not be used, or a plurality of conditions may be modified and used. Further, the control unit 250 uses the basis weight of the medium 50, the average value of the duty of the loaded media 50, and the average value of the waiting time after printing of the loaded media 50, and uses the average value of the waiting time after printing of the loaded media 50 to The height of the medium 50 may be estimated. Furthermore, the height of the medium 50 may be estimated using only the basis weight of the medium 50 and the number of sheets of the medium 50 loaded.

In step S606, the control unit 250 determines the size of the medium 50, the basis weight of the medium 50, the medium surface condition of the back surface 51b of the first medium 51, and the medium surface condition of the front surface 52a of the second medium 52. The operating method of the first drawing member 211 and the operating method of the second drawing member 212 are determined depending on the height of the medium 50 loaded on the intermediate tray 210.

As shown in FIGS. 13 and 14, the front duty, the back duty, the contact part surface duty, the contact part back duty, the front elapsed time, the back elapsed time, the environmental temperature, and the environmental humidity are the control unit 250 is a parameter that determines how the first retracting member 211 and the second retracting member 212 operate. Further, the size of the medium 50, the basis weight of the medium 50, and the number of sheets loaded on the intermediate tray 210 are parameters by which the control unit 250 determines the operating method of the first drawing member 211 and the second drawing member 212. At least one of the following may be used as a parameter: environmental temperature, environmental humidity, the size of the medium 50, the basis weight of the medium 50, and the number of media 50 loaded on the intermediate tray 210. .

Using those parameters, the first required number of rotations of the first retraction member 211, the height of the first retraction member 211, and the first required number of rotations are determined as the operation method of the first retraction member 211 and the second retraction member 212. The posture of the first retracting member 211 and the second required rotation speed of the second retracting member 212 when the rotation speed is reached can be set.

That is, the control unit 250 controls the first required number of rotations of the first retraction member 211, the height of the first retraction member 211, the attitude of the first retraction member 211 when the first required number of rotations is reached, and the second The second required number of rotations of the retracting member 212 is determined according to the parameter conditions.

The printing device control unit 60 and the control unit 250 of the post-processing device 200 complete the process of determining the operations of the first retraction member and the second retraction member. Note that in the case of single-sided printing, the parameters of back side duty, contact part back side duty, and back side elapsed time are not calculated and notified. Therefore, the control unit 250 determines the operating method of the retracting members 211 and 212 without using these parameters related to backside printing.

<Configuration of the first retracting member>
As shown in FIG. 15, the first blades 211a, 211b, and 211c of the first drawing member 211 are made of a material with a large friction coefficient, and have a shape that can be easily bent even with a small force, so that the medium 50 can be loaded. Even if the height changes, the structure is such that the change in the force for drawing the first medium 51 is reduced. For example, elongated wings of rubber material are fixed to multiple locations on the first core 211d. In this embodiment, first blades 211a, 211b, and 211c are fixed to three locations on the first core 211d.

The control unit 250 causes the first retracting member 211 to rotate at a constant speed using the first rotation motor 213 (see FIG. 11). When the first blade A211a hits the surface 51a of the first medium 51, a pulling force F11, which is the force of the first blade A211a to pull the medium 50, is generated.

Since the first drawing member 211 rotates, there is an angle at which none of the first blades 211a, 211b, and 211c hit the surface 51a of the first medium 51, and there is a period during which the drawing force F11 by the first drawing member 211 is not generated. There is also.

The intermediate tray 210 has a first rotational position sensor 254 (see FIG. 11), and the control unit 250 is configured to detect the positions of the first blades 211a, 211b, and 211c. For example, the first rotational position sensor 254 (see FIG. 11) is a photo-interrupter type optical sensor, and the first rotational position sensor 254 (see FIG. 11) is a photo-interrupter type optical sensor, and is attached to the rotation axis of the first retracting member 211 with a shield (not shown) between the light emitting part and the light receiving part of the first rotational position sensor. A shielding plate is provided.

When the first retracting member 211 rotates once, a shielding plate (not shown) of the first retracting member 211 allows the first retracting member 211 to move between the light emitting part and the light receiving part of the first rotational position sensor 254 at a predetermined angle. Configure it to shield when . For example, the predetermined angle is an angle when the base of the first blade C211c becomes perpendicular to the loading bottom surface 210b of the intermediate tray 210.

The time during which the first retracting member 211 rotates, or the time when the first retracting member 211 The control unit 250 can grasp the positions of the first blades 211a, 211b, and 211c based on the rotational speed. That is, the control unit 250 controls the drawing force F11 by stopping the rotation of the first drawing member 211 in a state where none of the first blades 211a, 211b, and 211c hit the surface 51a of the first medium 51. It is possible to prevent it from occurring.

When the first retracting member 211 continues the first retracting operation from the state shown in FIG. 15, the rear end 51c of the first medium 51 reaches the rear end alignment part 210a, as shown in FIG. 16. At this time, the first drawing member 211 rotates by the first required number of rotations, so that the side of the rear end 51c of the first medium 51 reliably contacts the rear end alignment part 210a. In addition, in order to bring the rear end 51c of the first medium 51 into contact with the rear end alignment part 210a more reliably, a predetermined number of rotations is provided after the first integrated rotation speed of the first drawing member 211 reaches the first required rotation speed. It may also be configured to draw in a fixed amount.

<Force generated when the first drawing member draws the first medium>
FIG. 15 shows the force generated when the first drawing member 211 draws in the first medium 51 in the state of the intermediate tray 210 shown in FIG. When the first retracting member 211 is driven, there are mainly five forces generated in the transport direction Y1.

As shown in FIG. 15, the first force is a retraction force F11 acting on the first retraction member 211. As shown in FIG. The drawing force F11 is a force that draws the first medium 51 to the upstream side in the transport direction Y1.
The retraction force F11 is a friction coefficient μ1a between the first retraction member 211 and the surface 51a of the first medium 51, a pressing force T1 that is a force with which the first retraction member 211 presses the surface 51a of the first medium 51, Determined by When either the friction coefficient μ1a or the pressing force T1 increases, the retraction force F11 increases. Hereinafter, they will be referred to as "friction coefficient μ1a" and "pressing force T1." The pressing force T1 is determined by the height of the first drawing member 211 and the stacking height of the media 50 loaded on the intermediate tray 210. As the pressing force T1 increases, the pulling force F11 increases.

When the pulling force F11 is large, the time required for the rear end 51c of the first medium 51 to reach the rear end alignment portion 210a becomes shorter. Conversely, when the pulling force F11 is small, it takes a long time for the rear end 51c of the first medium 51 to reach the rear end alignment part 210a.

As shown in FIG. 15, the second force is a frictional force F12 that acts between the first medium 51 and the second medium 52. The frictional force F12 is a frictional force generated when the first medium 51 and the second medium 52 come into close contact with each other, and is a force that obstructs the drawing force F11.

The frictional force F12 is the friction coefficient μ1b between the back surface 51b of the first medium 51 and the front surface 52a of the second medium 52, and the pressing force that is the force with which the first drawing member 211 presses the surface 51a of the first medium 51. It is determined by T1. When either the friction coefficient μ1b or the pressing force T1 increases, the friction force F12 increases.

As shown in FIG. 15, the frictional force F12 is a force generated in an area that overlaps with an area where the first drawing member 211 contacts the medium 50. As shown in FIG. Frictional force F12 acts between the back surface 51b of the first medium 51 and the front surface 52a of the second medium 52. That is, the frictional force F12 depends on the medium surface state of the back surface 51b of the first medium 51 and the medium surface state of the front surface 52a of the second medium 52 when the first drawing member 211 performs the first drawing operation. to be influenced. In particular, the medium surface state of the back surface 51b of the first medium 51 and the medium surface state of the surface 52a of the second medium 52 in the region overlapping with the region where the first drawing member 211 contacts the first medium 51. to be influenced.

The frictional force F12 is more influenced by the medium surface condition of the medium 50 than the pulling force F11. This is because when the medium 50 contains water, the rate at which the friction coefficient of the medium 50 increases is greater than the rate at which the friction coefficient of the material of the first blades 211a, 211b, and 211c increases. Therefore, when the medium 50 contains water, it becomes difficult for the first drawing member 211 to draw the first medium 51.

When the frictional force F12 is large, it takes a long time for the rear end 51c of the first medium 51 to reach the rear end alignment part 210a. If the frictional force F12 is very large, the first medium 51 may not move at all depending on the magnitude of the pulling force F11. Conversely, when the frictional force F12 is small, the time required for the rear end 51c of the first medium 51 to reach the rear end alignment portion 210a is shortened.

As shown in FIG. 15, the third and fourth forces are a resistance force F13 and a falling force F14 that act between the first medium 51 and the second medium 52. The resistance force F13 is a force that acts as a resistance when the first medium 51 is drawn in, and the falling force F14 is a force that causes the first medium 51 to slide down the slope due to gravity.

When the first drawing member 211 draws the first medium 51 by the drawing force F11, the first medium 51 is placed on the second medium 52. The dead weight of the first medium 51 is applied to the surface 52a of the second medium 52 even in areas other than the area where the first drawing member 211 contacts the first medium 51. That is, when the size of the medium 50 is large or when the basis weight of the medium 50 is large, the resistance force F13 and the falling force F14 become large. The falling force F14 is a force that helps the retracting force F11, and the resistance force F13, together with the frictional force F12, is a force that obstructs the retracting force F11. That is, the longer the length in the transport direction Y and the larger the basis weight of the paper, the greater the resistance force F13, and therefore it is necessary to set the drawing force F11 of the first drawing member 211 large.

As shown in FIG. 16, the fifth force is a restraining force F15 that acts between the rear end 51c of the first medium 51 and the rear end alignment portion 210a. The stopping force F15 is generated when the first medium 51 causes the rear end 51c of the first medium 51 to reach the rear end aligning portion 210a by the first pulling operation. This is a force that restrains the rear end aligning portion 210a while it remains in contact with the rear end aligning portion 210a. Due to the restraining force F15, when the rear end 51c of the first medium 51 hits the rear end alignment part 210a of the intermediate tray 210, the rigidity of the first medium 51 prevents the second medium from moving.

When the first medium 51 comes into contact with the rear end alignment part 210a, if the first medium 51 has a large weight and the falling force F14 is large, the first drawing member 211 is not performing the first drawing operation. Also, the medium 50 with a small basis weight is likely to buckle.

When the moisture content of the first medium 51 increases when the first drawing member 211 performs the first drawing operation, the first medium 51 becomes less rigid and becomes easily bent, and the stopping force F15 becomes smaller. When the first drawing member 211 continues the first drawing operation even after the side of the rear end 51c of the first medium 51 comes into contact with the rear end alignment part 210a, the rear end 51c of the first medium 51 It becomes easier to buckle.

<Force generated when the second drawing member draws the first medium>
FIG. 17 shows the force generated when the second drawing member 212 draws in the first medium 51 in the state of the intermediate tray 210 shown in FIG. When the second retracting member 212 is driven, there are mainly four forces generated in the transport direction Y1.

As shown in FIG. 17, the drawing force F21, the frictional force F22, and the falling force F24 will be explained in the same way as in the case of the first drawing member, so the explanation will be omitted. As in the case of the first retracting member 211, the pressing force will hereinafter be referred to as "pressing force T2." The difference from the case of the first retracting member 211 is the resistance force F23, and only the difference from the case of the first retracting member 211 will be explained.

When the second retracting member 212 starts the second retracting operation, the distance between the rear end 51c of the first medium 51 and the rear end 52c of the second medium 52 is large. However, since the weight of the first medium 51 that is protruding from the tip 52d of the second medium 52 is concentrated on the tip 52d of the second medium 52, the overlapping area is small. Almost the same resistance force F23 as in the case of the first retracting member 211 is generated. That is, the longer the length in the transport direction Y and the larger the basis weight of the sheet, the greater the resistance force F23, and therefore it is necessary to set the drawing force F21 of the second drawing member 212 large.

<Force generated when the intermediate ejection roller pair ejects the medium>
As shown in FIGS. 18 and 19, when the pair of intermediate discharge rollers discharges the first medium, there are mainly three forces that are generated in the transport direction Y1. 18 and 19 show the force generated when the intermediate ejection roller pair 202 ejects the first medium 51 to the intermediate tray 210 in the state of the intermediate tray 210 shown in FIG.

The first force is a pushing force F31 that acts between the first medium 51 and the second medium 52. When the intermediate discharge roller pair 202 discharges the first medium 51 onto the intermediate tray 210, a pushing force F31 is generated. The pushing force F31 is the force by which the first medium pushes the second medium.

The pushing force F31 is determined by the friction coefficient μ1b between the back surface 51b of the first medium 51 and the front surface 51a of the second medium 52, and the friction coefficient μ1b between the back surface 51b of the first medium 51 and the front surface 51a of the first medium 51. It is determined by the pressing force T3, which is the force for pressing . When either the pressing force T3 or the friction coefficient μ1b increases, the pressing force F31 increases.

When the first medium 51 has a high rigidity, the pressing force T3 is large. When the first medium 51 is large in size or basis weight when the intermediate discharge roller 202 pair discharges the first medium 51, the pressing force T3 is large because the first medium 51 has a large rigidity. If the length of the rear end 51c of the first medium 51 in the conveyance direction Y1 conveyed from the intermediate discharge roller pair 202 when the rear end 51c of the first medium 51 is discharged to the intermediate tray 210 is long, the first medium 51 is the second medium. Since the area of the portion pressing 52 becomes large, the pressing force T3 is large. When the stacked height of the media 50 stacked on the intermediate tray 210 is high, the amount of deflection of the media 50 becomes large, so the pressing force T3 is large.

Regarding the friction coefficient μ1b, the explanation is the same as that for the friction force F12 of the first retracting member, so the explanation will be omitted.
As shown in FIGS. 18 and 19, the second force is a resistance force F32 that acts between the first medium 51 and the second medium 52. The resistance force F32 is caused by a frictional force that acts as resistance when the back surface 51b of the first medium 51 rubs and pushes against the surface 51a of the second medium 52, and a rear end 52c of the second medium 52 that is pushed against the rear end by gravity. This is the resultant force of the falling force that attempts to maintain the state in which it hits the alignment part 210a.

The direction in which the first drawing member 211 and the second drawing member 212 draw the first medium 51 is a direction that follows the force of gravity, whereas the direction in which the first medium 51 pushes the second medium 52 is a direction that follows the force of gravity. It is in the opposite direction. Therefore, since the resistance force and the falling force become forces in the same direction, the resultant force of the two becomes the resistance force F32. The resistance force F32 is a force in the opposite direction to the pushing force F31 that attempts to move the second medium 52, and is a force that grips the second medium 52 in the aligned position.

As shown in FIG. 18, the third force is a gripping force F33 that acts between the first drawing member 211 and the surface of the second medium 52.
As shown in FIG. 18, in the present embodiment, the control unit 250 lowers the height of the first retracting member 211 using the first vertical movement motor (see FIG. 11) 253, and The rotation of the first drawing member 211 is stopped while both of the blades C211c remain in contact with the surface 51a of the first medium 51. That is, with the first drawing member 211 in contact with the first medium 51, the first drawing operation of the first drawing member 211 is stopped, the height of the first drawing member 211 is lowered, and the first drawing member 211 is in contact with the first medium 51. The configuration is such that it can be changed to a second posture in which the first medium 51 is pressed down. With this configuration, the first retracting member 211 can prevent misalignment due to the pushing force F31.

Further, when changing the attitude of the first retracting member 211 to the second attitude, the first retracting member 211 may not stop rotating but may be configured to reduce its rotation speed. Even in this case, misalignment due to the pushing force F31 can be prevented.

The first retracting member 211 can continue to rotate without reducing its speed and can continue to hold down the medium 50 in the first posture. However, by continuing to apply the pulling force F11, the rear end 52c of the second medium 52 will gradually curl, and there is a risk that the rear end 52c of the second medium 52 will be bent and stacked, or it may not sit in the intermediate tray 210. There is a risk that bending may occur, or there may be scratches or pressure marks. The longer it is spinning, the greater the risk.

Therefore, as shown in FIG. 19, the control unit 250 moves the first retracting member 211 from the first attitude to the first position when the first integrated rotational speed reaches the first required rotational speed according to the parameter conditions. The configuration is such that it can be moved to a third attitude in which it is separated from the medium. The control unit 250 is configured so that the first drawing member 211 does not come into contact with the surface 51a of the first medium 51, thereby making it difficult to leave scratch marks or push marks.

Depending on the conditions of the first medium 51 and the second medium 52, the pushing force F31 can be suppressed only by the resistance force F32, which is a force for gripping the second medium 52 in the alignment position. However, when the moisture content of the first medium 51 and the second medium 52 is high, the friction coefficient μ1b between the media becomes high. The medium 52 may be moved. When the rear end 52c of the second medium 52 moves away from the range where the first drawing member 211 hits due to the pushing force F31, a means for returning the rear end 52c of the second medium 52 to the rear end alignment part 210a. There is nothing, and the first drawing operation of the first medium is started while the rear end 52c of the second medium 52 remains separated from the rear end alignment part 210a. Therefore, such misalignment can be avoided by changing the attitude of the first retracting member 211 according to the parameter conditions that affect the medium surface state of the back surface 51b of the first medium 51 and the front surface 52a of the second medium 52. It can be prevented.

<Control table for increase in required rotation speed by parameters>
The first retracting member when operating the post-processing device on a standard medium that is not printed at all when the printing system 11 is operated at the environmental temperature and humidity in the standard operating environment of the printing system 11. Let the first required rotation speed of 211 be the first standard rotation speed, and the second required rotation speed of the second retracting member be the second standard rotation speed. For example, the standard media is A4LEF size and 70 gsm media, which is the type of media that users are recommended to use with the printing device 13. LEF is an abbreviation for Lateral Feed, in which the medium 50 is transported with the long side leading, and SEF is an abbreviation for Longitudinal Feed, in which the medium 50 is transported with the short side leading. be done.

The first required rotation speed and the second required rotation speed are determined by the post-processing device 200 for the medium 50 that has not been printed at all due to an increase in the moisture content of the medium 50 and the effects of waving that occurs during the subsequent drying process. is larger than the first standard rotation speed and the second standard rotation speed when performing post-processing.

FIG. 20 is a control table for increasing the required number of rotations applied to the first drawing member 211 and the second drawing member 212 when the length of the medium 50 in the conveying direction is 210 mm or less. The control unit 250 determines the required increase in the number of rotations according to the parameter conditions when the installation environment is at normal temperature and normal humidity. The control table lists the required increase in rotation speed for each parameter condition. "+1" indicates that the rotation speed is increased by one step relative to the standard rotation speed.

The number of rotations in one stage varies depending on the configuration of the device. The configuration of the device is, for example, factors that determine the drawing force F11 and the frictional force F12, such as the type of liquid used in the liquid discharge part 27 and the material and shape of the first drawing member 211. Note that the values of F%, H sheets, and Jsec are determined depending on the configuration of the apparatus. The number of rotations for one stage may be changed depending on the first required rotation number and the second required rotation number.

In the control table of FIG. 20, in this embodiment, the print duty is divided into two or three, and the waiting time corresponding to the elapsed time is divided into two, but this may be divided into any number of divisions. The basis weight and number of sheets to be loaded on the medium 50 may be divided into any number of divisions. However, if the change in the medium surface condition is large due to a wide printing duty range, etc., the range of the friction coefficient μ1b becomes wide, so the more the number of divisions of the parameter conditions, the more accurate control becomes possible.

When the first drawing member 211 draws the first medium 51, the ease with which the first medium 51 is drawn is determined by the friction coefficient μ1b between the back surface 51b of the first medium 51 and the surface 52a of the second medium 52. It's decided. Therefore, the required increase in the number of rotations of the first drawing member 211 can be determined based on the parameter conditions of the back surface 51b of the first medium 51 and the parameter conditions of the front surface 52a of the second medium 52.

As shown in FIG. 20, for example, when double-sided printing is performed on a medium of A4LEF size and basis weight of 90 gsm, it is assumed that the surface duty of the second medium is F% or more and the number of sheets loaded exceeds H number of sheets. At that time, when the backside duty of the first medium 51 is F% or more and the waiting time exceeds Jsec, the first required rotation speed and the second required rotation speed are the first standard rotation speed and the second standard rotation speed. 6 steps more than that.

For media 50 with a small basis weight, the back side is affected by the moisture content of the front side, and the front side is affected by the moisture content of the back side, so the moisture content of the back side is taken into account on the front side, and the front side is affected by the moisture content on the back side, and numerical values are set as parameter conditions. may be adjusted. In particular, when there are many media 50 loaded on the intermediate tray 210, the media surface condition of the second medium is affected by the moisture content of the media 50 loaded so far, and the undulation becomes large. Height fluctuates. Therefore, the influence of the water content state of the medium 50 loaded so far may be taken into consideration, and the numerical value may be adjusted as a parameter condition.

FIG. 21 is a control table for increasing the required number of rotations applied to the first drawing member 211 and the second drawing member 212 when the length of the medium 50 in the conveying direction is 210 mm or more. The control unit 250 determines the required increase in the number of rotations according to the parameter conditions when the installation environment is at normal temperature and normal humidity. In the control table of FIG. 21 as well, the print duty and standby time may be divided into any number of divisions. The basis weight and number of sheets to be loaded on the medium 50 may be divided into any number of divisions.

When the length of the medium in the transport direction Y1 increases, the overall printing duty of the medium 50 may be different from the printing duty at the locations where the first drawing member 211 and the second drawing member 212 contact. Therefore, in this embodiment, when the length of the medium in the transport direction Y1 is long, the control unit 250 uses the contact portion duty instead of the printing duty of the entire medium 50.

In FIGS. 20 and 21, the control unit 250 uses the control table for normal temperature and normal humidity conditions, but depending on the environmental conditions, it can also use control tables for high temperature and high humidity, low temperature and low humidity, high temperature and low humidity, and low temperature and high humidity. use. In general, the waiting time is often the most dominant over the elapsed time, so in the control tables of FIGS. 20 and 21, the waiting time is used as the elapsed time. If the printing time is slow, the conveyance speed and printing time may be added as parameters to the control table. Furthermore, if the conveyance pitch time is long, the conveyance pitch time may be added as a parameter to the control table.

Also, fewer parameters may be used in the control table. The control unit 250 may use at least one of the standby time, print duty, and size of the medium 50 as a parameter. As shown in FIGS. 20 and 21, when any one of the standby time, print duty, and size of the medium 50 is used as a parameter, the larger the value of the parameter, the more The rotation speed increases.

In the post-processing device 200 that processes the medium 50 printed with the liquid discharged by the liquid discharge section 27, the rear end 52c of the second medium 52 gradually moves as the first retraction member 211 continues to apply the retraction force F11. There is a risk of buckling. The longer it is spinning, the greater the risk. Therefore, the control unit 250 needs to stop the first retracting member 211 at an appropriate first standard rotation speed.

In addition, when the friction coefficient μ1b between the media is large due to deterioration of the medium surface condition due to water content, if the first drawing member 211 continues to apply the drawing force F11 for a short time, the rear end 51c of the first medium 51 It does not reach the matching part 210a. Therefore, the control unit 250 needs to rotate the first retracting member 211 to an appropriate first standard rotation speed.

The operation of this embodiment will be explained.
<Effects on print jobs>
First, the operation when the post-processing device 200 processes the medium 50 printed with the liquid ejected by the liquid ejecting section 27 in a print job will be described.

A case will be described in which a medium 50 of A3SEF size and basis weight of 90 gsm is printed on both sides, 50 sheets are stacked on the intermediate tray 210, and are discharged to the discharge stacker 231. The control table of Figure 21 is used. In this embodiment, since the length of the medium in the transport direction Y1 is long, the control unit 250 uses the contact portion duty instead of the printing duty of the entire medium 50.

In the first medium 51, the contact portion surface duty is F% or more and the standby time Jsec is exceeded, and the contact portion back surface duty is less than F%.
When the first medium 51 is discharged onto the intermediate tray 210, there is no medium 50 on the intermediate tray 210. The first retracting member 211 is on standby in the third attitude. In the state shown in FIG. 19, there is no second medium 52 on the intermediate tray 210. At this time, the back surface 51b of the leading end of the first medium 51 does not hit the surface of the intermediate tray 210 and falls onto the intermediate tray 210. In other words, it falls onto the intermediate tray 210 without the thrust force F31 and resistance force F32 being generated.

When the first medium 51 falls onto the intermediate tray 210, the second retracting operation of the second retracting member 212 is started. In the state shown in FIG. 17, one A3SEF size medium 50 has fallen onto the intermediate tray 210. At this time, the friction force F12 and the resistance force F13 act between the back surface 51b of the first medium 51 and the surface of the intermediate tray 210, so that there is almost no influence of the water content state. That is, the second required number of rotations is made the same as the second standard number of rotations.

When the first medium 51 reaches the first retraction member 211, the first retraction member 211 starts rotating. For the same reason as for the second retracting member 212, the first required rotation speed of the first retraction member 211 is set to be the same as the first standard rotation speed. When the next second medium 50 is discharged onto the intermediate tray 210, the first drawing member 211 stops rotating after rotating by the first required number of rotations, and changes its posture to the second posture (see FIG. 19). change to

The timing to stop the second pulling operation may be immediately before aligning the rear end 51c of the first medium 51 with the rear end aligning portion 210a, or may be at the timing when the rear end 51c of the first medium 51 is aligned. However, this is before the timing at which the first retracting member 211 stops the first retracting operation. The control unit 250 causes the second rotary motor 214 (see FIG. 11) to stop the rotation of the second retracting member 212 at the timing when the rotational position of the second retracting member 212 reaches the standby angle position.

Also in the second first medium 51, the contact portion surface duty is F% or more and exceeds the standby time Jsec, and the contact portion back surface duty is less than F%.
When the second first medium 51 is discharged onto the intermediate tray 210 by the pair of intermediate discharge rollers 202, the back surface 51b of the first medium 51 hits the front surface 52a of the second medium 52, so that a pushing force is generated. F31 occurs. In the state shown in FIG. 18, there is one A3SEF size medium 50 on the intermediate tray 210. However, the first retracting member 211 waits in the second posture (see FIG. 18) and generates the gripping force F33, so the second medium 52 does not move.

When the first medium 51 falls onto the intermediate tray 210, the second retracting operation of the second retracting member 212 is started. In FIG. 17, there are two A3SEF size media 50 on the intermediate tray 210. The water content state of both media surfaces is slightly deteriorated, and the friction coefficient μ1b between the media becomes large. Since almost the entire back surface 51b of the first medium 51 of A3SEF size hits almost the entire surface 51a of the second medium 52 of A3SEF size, a resistive force F23 is generated. That is, the necessary retraction force F21 increases due to both the friction force F22 and the resistance force F23. The control unit 250 refers to the control table of FIG. 20 and increases the second required rotation speed by two steps compared to the second standard rotation speed.

When the first medium 51 reaches the first drawing member 211, the first drawing member 211 shifts its attitude to the first attitude and starts rotating. The control unit 250 refers to the control table in FIG. 21 and increases the first required rotation speed of the first retraction member 211 by two steps compared to the first standard rotation speed for the same reason as the second retraction member 212. After the first retracting member 211 rotates by the first required number of rotations, the first retracting member 211 stops rotating and changes its posture to the second posture (see FIG. 18).

After the second sheet of first media 51 is properly aligned, the second retraction member 212 stops rotating. Therefore, it is possible to suppress the occurrence of misalignment of the media 50 or buckling in the intermediate tray 210 due to the first medium 51 not being drawn in or being drawn in too much.

By repeating this operation for the third and subsequent sheets, the media 50 can be properly aligned. Thereafter, the media 50 are stacked one after another on the intermediate tray 210 and aligned. The number of media 50 stacked on the intermediate tray 210 increases. The number of media 50 is calculated based on the number of sheets loaded on the intermediate tray 210, the size of each medium 50, the front duty of each medium 50, the back duty of each medium 50, the elapsed time on the front side of each medium 50, and the elapsed time on the back side of each medium 50. Estimate the height of.

If the estimated loading height of the medium 50 is higher than the standard loading height, the pulling force F11 of the first pulling member 211 and the pulling force F21 of the second pulling member 212 become large, so the control unit 250 The values of the first required number of rotations and the second required number of rotations may be adjusted appropriately. Therefore, it is possible to prevent buckling from occurring in the intermediate tray 210 due to the first medium 51 being drawn in too much.

The control unit 250 uses control tables for high temperature and high humidity, low temperature and low humidity, high temperature and low humidity, and low temperature and high humidity depending on the environment. The control unit 250 may have more classifications for both temperature and humidity, and may use even more control tables.

Instead of increasing the first necessary number of revolutions of the first retracting member 211 by several steps compared to the first standard number of revolutions, the control unit 250 increases the height of the first retracting member 211 in the first posture by several steps. The retraction force F11 may be increased by lowering the value. The control unit 250 controls the height of the first retracting member 211 using the tables shown in FIGS. 20 and 21.

The distance by which the control unit 250 moves the height of the first retracting member 211 in one step varies depending on the configuration of the device. The configuration of the device is, for example, a factor that determines the drawing force F11 and the frictional force F12, such as the type of liquid and the material and shape of the first drawing member 211. Moreover, the shorter the length of the first blades 211a, 211b, 211c of the first retracting member 211, the greater the rate at which the retracting force F11 changes with height, and therefore, fine adjustment is required. The control unit 250 may control both the first required number of rotations and the height of the first posture of the first retracting member 211.

When the length of the medium in the transport direction Y1 is short, such as A4LEF, and the number of sheets stacked on the intermediate tray 210 is small, when the first medium 51 is discharged onto the intermediate tray 210, the first medium 51 Since the back surface 51b of the second medium 52 does not touch the front surface 52a of the second medium 52, the pushing force F31 is not generated. The posture of the first drawing member 211 when discharging the first medium 51 may be the third posture. However, when the number of sheets stacked on the intermediate tray 210 increases, when the first medium 51 is ejected onto the intermediate tray 210, the back surface 51b of the first medium 51 comes into contact with the front surface 52a of the second medium 52. As a result, the pushing force F31 is generated, which may cause the media 50 to be misaligned. Therefore, when the number of sheets loaded on the intermediate tray 210 reaches a certain value, the control unit 250 changes the attitude of the first retracting member 211 from the third attitude to the second attitude when ejecting the first medium 51. Good too.

<Effect in test processing of post-processed media>
Next, an explanation will be given of the operation when a service person performs a test process of printing a test pattern for measuring the alignment accuracy of the trailing edge of the post-processed medium 50.

If the alignment of the media bundles discharged to the discharge stacker 231 is not good, the service person operates the operation unit 62 to shift the printing system 11 to a test mode and executes an arbitrary test process. A test pattern and job content that are close to the print image in which the mismatch of the medium 50 has occurred are selected from among the plurality of test patterns. The job contents include the basis weight of the medium 50, the size of the medium 50, the size of the medium 50, and the number of copies. Then, the print job is executed using the same medium as the one in which the mismatch occurred.

Depending on the state of the medium bundle discharged to the discharge stacker 231, the service person determines the first required number of rotations of the first drawing member 211, the height of the first drawing member 211, and the second required number of rotations of the second drawing member 212. Change the rotation speed. The changing method involves displaying a control table used by the control unit 250 as shown in FIGS. 20 and 21 on the touch panel of the operation unit 62, and changing each value in the table. The printing device control unit 60 communicates with the control unit 250 of the post-processing device 200 and notifies the control unit 250 of the changed value.

After completing the settings, the service person executes the test process again. The service engineer checks the state of the media bundle ejected to the ejection stacker 231, and if there is a medium 50 that is not pulled in enough or pulled in too much in the media bundle ejected to the ejection stacker 231, the service person controls the Change the amount of pull by adjusting the values in the table.

Regarding the attitude of the first retracting member 211 when the first required number of rotations is reached, the service person switches the screen of the operation unit 62 to a screen different from the control table. On the screen, the service person changes the attitude of the first retracting member 211 according to the job content.

The service engineer checks the state of the media bundle ejected to the ejection stacker 231, and if the media bundle ejected to the ejection stacker 231 protrudes greatly in the transport direction Y1, the service engineer confirms that the intermediate ejection roller pair 202 The attitude of the first drawing member 211 when discharging the first medium 51 is changed from the third attitude to the second attitude. Alternatively, the service person reduces the number of sheets loaded on the intermediate tray 210 in which the posture of the first drawing member 211 is changed from the third posture to the second posture when the intermediate discharge roller pair 202 discharges the first medium 51. .

If there are scratch marks, push marks, etc. in the place where the first drawing member 211 hits, the service engineer should check the position of the first drawing member 211 when the intermediate ejection roller pair 202 ejects the first medium 51. Change to the third posture.

After completing the settings, the service person executes the test process again. If the alignment of the media bundle ejected to the eject stacker 231 is improved, the test process ends. If the alignment of the media bundle is not improved, the service person operates the operation unit 62 to make adjustments again and executes a test process. If the media bundle alignment is improved, the test process ends.

The effects of this embodiment will be explained.
(1) The control unit 250 determines, according to the parameter conditions, that the first cumulative number of rotations after starting the first retraction operation is necessary for aligning the rear end of the medium 50 with the rear end alignment unit 210a. The first retracting operation is regulated when the first required number of rotations is reached. When the media 50 printed by the liquid discharged by the liquid discharge unit 27 are aligned, the first medium 51 drawn in by the first drawing member 211 in the intermediate tray 210 and the first medium 51 loaded previously on the intermediate tray 210 are aligned. The friction coefficient μ1b with the second medium 52 changes depending on the parameter conditions. Therefore, the time required for the rear end 51c of the first medium 51 to reach the rear end alignment section 210a changes. Therefore, the control unit 250 sets an appropriate first required rotation speed according to the parameter conditions. Therefore, when aligning the medium 50 on the intermediate tray 210, there may be misalignment of the medium 50 due to the rear end of the medium 50 not reaching the rear edge alignment section 210a, or the rear end of the medium 50 may not reach the rear edge alignment section 210a. It is possible to suppress buckling of the medium 50 caused by the medium 50 being retracted even after it has been moved.

As a method for regulating the first retracting operation, there is a method in which the control unit 250 changes the first retracting member 211 to the second posture. By stopping the rotation of the first drawing member 211 at an appropriate rotation speed and pressing the first medium 51, it is possible to suppress misalignment of the medium 50 and occurrence of buckling in the intermediate tray 210.

As a method for regulating the first retracting operation, there is a method in which the control unit 250 changes the first retracting member 211 to the third attitude. By moving the first drawing member 211 to a position where it does not hit the first medium 51, it is possible to suppress the formation of scratch marks, push marks, etc. on the medium 50.

(2) The control unit 250 controls the temperature of the environment where the printing device 13 is installed, the humidity of the environment where the printing device 13 is installed, the size of the medium 50, the basis weight of the medium 50, and the intermediate tray 210. The number of media 50 loaded on the media 50 is used as a parameter condition. When the temperature of the environment is low, the liquid adhering to the medium 50 is difficult to dry, and the friction coefficient μ1b between the media becomes large, so the frictional force F12 and the resistance force F13 become large. Furthermore, when the humidity of the environment is high, the liquid adhering to the medium 50 is difficult to dry, and the friction coefficient μ1b between the media becomes large, so the frictional force F12 and the resistance force F13 become large. Furthermore, the larger the size of the medium 50, the larger the contact area between the media, and therefore the resistance force F13 increases when the first drawing member pulls in the long medium 50 in the transport direction Y1 of the medium 50. Moreover, since the weight of the medium 50 is larger as the basis weight of the medium 50 is larger, the resistance force F13 becomes larger when the first drawing member 211 draws the medium 50. The smaller the basis weight of the medium 50 is, the weaker the rigidity of the medium 50 is, so the restraining force F15 is smaller, and the first medium 51 is more likely to buckle. Further, as the number of media 50 stacked on the intermediate tray 210 increases, the stacking height of the media bundle becomes higher, and the first media 51 approaches the first pull-in member 211. Since the pressing force T1 when 211 pulls in the first medium 51 increases, the frictional force F12 increases. The control unit 250 controls the control unit 250 according to at least one parameter among the temperature of the environment, the humidity of the environment, the size of the medium 50, the basis weight of the medium 50, and the number of sheets of the medium 50 loaded on the intermediate tray 210. By appropriately setting the first required rotation speed, it is possible to suppress irregularities in the medium 50 and buckling of the medium 50.

(3) The control unit 250 uses at least one of elapsed time, standby time, and print duty as a parameter. The shorter the elapsed time, the longer the standby time, and the larger the printing duty, the lower the degree of dryness of the liquid that has adhered to or permeated the medium 50, and the moisture state of the medium surface tends to deteriorate. When the water content state of the medium surface deteriorates, the friction coefficient μ1b between the media increases, and therefore the frictional force F12 and the resistance force F13 increase. The control unit 250 appropriately changes the first required rotation speed according to at least one parameter among elapsed time, standby time, and print duty. Therefore, when aligning the media 50 on the intermediate tray 210, it is possible to suppress misalignment of the media 50 and buckling of the media 50.

(4) The elapsed time is the printing time on the medium 50 printed with the liquid ejected by the liquid ejecting unit 27, the transport time on the medium 50 printed with the liquid ejected by the liquid ejecting unit 27, and the transport pitch time. At least one of them. The shorter at least one of printing time, conveyance time, and conveyance pitch time is, the more likely the water content state of the medium surface becomes worse. When the water content state of the medium surface deteriorates, the friction coefficient μ1b between the media increases, and therefore the frictional force F12 and the resistance force F13 increase. Therefore, the control unit can suppress unevenness of the medium and buckling of the medium by appropriately changing the first required rotation speed according to at least one parameter among printing time, conveyance time, and conveyance pitch time. .

(5) The control unit 250 uses at least one of the standby time, the print duty of the liquid, and the size of the medium 50 as a parameter, and the larger the numerical value of the parameter, the larger the first required number of revolutions. When the standby time is long, it is necessary to ensure a long drying time for the medium 50. Therefore, while the water content state of the medium surface is still deteriorated, the waviness of the medium surface further increases, and the friction coefficient μ1b between the media increases, so that the frictional force F12 and the resistance force F13 increase. Further, when the printing duty is large, the moisture content of the medium surface is still in a deteriorated state, and the friction coefficient μ1b between the media becomes large, so that the frictional force F12 and the resistance force F13 become large. When the size of the medium 50 is large, the contact area is large, so the resistance force F13 becomes even larger. The control unit 250 increases the first required number of revolutions and increases the pulling amount as the numerical value of at least one parameter among the waiting time, print duty, and size of the medium 50 increases, thereby preventing irregularities in the medium 50. Buckling of the medium 50 can be suppressed.

(6) The printing duty may be a contact portion duty in a region where the first drawing member 211 contacts the medium 50 or a region overlapping the contact region. When the first drawing member 211 draws in the first medium 51, the frictional force F12 changes depending on the friction coefficient μ1b between the media in the area that contacts the first medium 51 or the area that overlaps with the contact area, and the first The ease with which the medium 51 can be pulled in changes. It is better to use the contact part duty than to use the print duty because the area that contacts the first medium 51 when the first drawing member 211 draws the first medium 51 or the area that overlaps with the contact area The friction coefficient μ1b between the media is more accurately reflected. Therefore, by the control unit 250 appropriately changing the first required number of rotations according to the contact portion duty, it is possible to suppress irregularities in the medium 50 and buckling of the medium 50.

(7) The control unit 250 uses the print duty on the back side of the first medium 51 and the size of the first medium 51 as parameters. When the printing duty is large, the friction coefficient μ1b between the media increases due to deterioration of the water content state of the media surface, so the frictional force F12 and the resistance force F13 increase. The printing duty is a parameter that has the greatest influence on the medium surface condition of the back surface of the first medium 51. When the size of the first medium 51 is large, the resistance force F13 becomes large. That is, by appropriately changing the first required rotation speed, the control unit 250 can suppress irregularities in the medium 50 and buckling of the medium 50 even if the size of the first medium 51 changes.

(8) The control unit 250 uses the printing duty on the back side of the first medium 51 and the environmental humidity as parameters. When the printing duty is large, the friction coefficient μ1b between the media increases due to deterioration of the water content state of the media surface, so the frictional force F12 and the resistance force F13 increase. The printing duty is a parameter that has the greatest influence on the medium surface condition of the back surface of the first medium 51. When the environmental humidity is high, the friction coefficient μ1b between the media becomes large, so the frictional force F12 and the resistance force F13 become large. That is, by appropriately changing the first required number of rotations, the control unit 250 can suppress unevenness of the medium 50 and buckling of the medium 50 even if the humidity of the environment changes.

(9) The control unit 250 controls the printing duty on the back side of the first medium 51, the printing duty on the front side of the second medium, the elapsed time on the back side of the first medium 51, and the elapsed time on the front side of the second medium 52. time is used as a parameter. This is caused by the friction coefficient μ1b between the media, which changes depending on the water content state of the back surface of the first medium 51 and the water content state of the surface of the second medium 52 when the first drawing member 211 performs the first drawing operation. By appropriate control according to changes in the frictional force F12 and the resistance force F13, it is possible to suppress irregularities in the medium 50 and buckling of the medium 50.

(10) The control unit 250 can appropriately adjust the retraction force F11 by determining the height of the first retraction member 211 in the first posture according to the parameter conditions. By appropriately determining the retraction force F11, it is possible to suppress the occurrence of irregularities in the medium 50 and buckling of the medium 50.

(11) In a state where the first drawing member 211 is in contact with the first medium 51, the control unit 250 stops the first drawing operation of the first drawing member 211 to lower the height, and the control unit 250 causes the first drawing member 211 to The second posture is changed to a second posture in which the second medium 52 is pressed down. Since the gripping force F33 is generated in the opposite direction to the pushing force F31 generated when the intermediate discharge roller pair 202 discharges the first medium 51, movement of the aligned second medium 52 can be suppressed.

(12) When the first retracting member 211 is in the second attitude, the control unit 250 causes the second retracting member 212 to start the second retracting operation, so that the rear end 51c of the first medium 51 is in the first retracting member. 211, the first retracting member 211 is returned from the second posture to the first posture and the first retracting operation is restarted. The first retracting member 211 suppresses movement of the aligned second medium 52 when the first retracting member 211 is in the second posture, and suppresses movement of the first medium 52 due to the first posture of the first retracting member 211. It is possible to achieve both consistency.

(13) The control unit 250 changes the first retracting member 211 from the first attitude to the third attitude in which it is separated from the first medium 51. By shortening the time during which the first drawing member 211 is in contact with the surface 51a of the first medium 51, the first blades 211a, 211b, 211c of the first drawing member 211 are less likely to leave scratch marks, push marks, etc. be able to.

(14) When the first retracting member 211 is in the third attitude, the second retracting member 212 starts the second retracting operation, and when the rear end of the first medium 51 reaches the first retracting member 211 , the first retracting member 211 returns from the third attitude to the first attitude and resumes the first retracting operation. The first retracting member 211 can both suppress scratch marks and push marks on the second medium 52 and align the first medium 51 in the first posture.

(15) The control unit 250 regulates the second retracting operation when the second integrated rotational speed reaches the second required rotational speed. The friction coefficient μ1b between the media changes depending on the parameters acquired from the printing device 13, and the time it takes for the trailing edge of the media 50 to reach the trailing edge aligning section 210a becomes longer. Set the second required rotation speed. Therefore, irregularities in the medium 50 and buckling of the medium 50 can be suppressed.

(16) The printing system determines the first required rotation speed according to the parameter conditions. The friction coefficient μ1b between the media changes depending on the parameters acquired from the printing device 13, and the time it takes for the trailing edge of the media 50 to reach the trailing edge aligning section 210a becomes longer. Set the first required rotation speed. Therefore, irregularities in the medium 50 and buckling of the medium 50 can be suppressed.

(17) The service person performs a test process to print a test pattern, and depending on the result of the test process, determines the first required rotation speed of the first retracting member 211 and the rotation speed when the first retracting member 211 is in the first posture. At least one of the height and height can be changed. By adjusting the operation of the first retracting member 211 according to the test results, the service person can suppress misalignment of the medium 50 and buckling of the medium 50.

This embodiment can be modified and implemented as follows. This embodiment and the following modified examples can be implemented in combination with each other within a technically consistent range.
- The post-processing device 200 may not include the conveyance path 17, and the intermediate tray 210 may be connected to the conveyance path 17 on the printing device 13 side. In that case, the pair of transport rollers of the printing device 13 that discharges the medium 50 to the post-processing device 200 may be used as the pair of intermediate discharge rollers 202. Further, the paper detection sensor of the printing device 13 may be used as the receiving sensor 203.

- The first retracting member 211 includes first blades 211a, 211b, and 211c in a half-circumference range of the first rotation center 211e on the surface of the first core 211d, but includes first blades in the entire circumference range. You can do it like this.

- Although the first retracting member 211 includes three first blades 211a, 211b, and 211c, the number is not limited. Typically, the number of first vanes ranges from three to six.
- When the attitude of the first retracting member 211 is the second attitude, the angle is not limited to the angle of this embodiment.

- When the attitude of the first retracting member 211 is the third attitude, the angle is not limited to the angle of this embodiment.
- When the posture of the first retracting member 211 is the third posture, the first retracting member 211 may remain rotated.

- Although the second retracting member 212 includes three second blades 212a, 212b, and 212c, the number is not limited. Typically, the number of first vanes ranges from three to six.
- The first retracting member 211 and the second retracting member 212 may be rollers. By using a material such as sponge-like low-friction silicone whose coefficient of friction can be set between that of resin and rubber, the first medium 51 can be conveyed with a weak force. By causing the first medium 51 to slip between the medium surface of the first medium 51 and the roller surface, when the rear end 51c of the first medium 51 hits the rear end alignment part 210a, the first Media 51 does not buckle.

- The second retracting member 212 includes second blades 212a, 212b, and 212c in a half circumference range of the second rotation center 212e on the surface of the second core 212d, but includes second blades in the entire circumference range. You can do it like this. When second blades are provided around the entire circumference, one of the second blades will hit the surface 51a of the first medium 51 regardless of the angle of the second drawing member 212. A motor is added to the configuration to move the height up and down. In that case, the height of the second drawing member 212 is increased so that the second blade of the second drawing member 212 does not hit the surface 51a of the first medium 51.

- The surface of the medium 50 may be divided into a plurality of areas, the moisture content may be calculated for the plurality of areas, and the magnitude of the variation in the moisture content of the plurality of areas may be used as a parameter. If there is a large variation in the moisture content in a plurality of areas, warpage or distortion of the medium is likely to occur not only in the transport direction Y1 but also in the width direction X. Therefore, when the medium 50 falls onto the intermediate tray 210, the skew becomes large, and there is a possibility that it will take time to align the rear end. When a convex portion is generated due to distortion of the medium 50, force is concentrated on the convex portion and the pushing force F31 increases, so that the effect of the second posture for pressing the first medium 51 becomes greater.

- The regulation of the first pull-in operation may be performed on the first medium 51 multiple times. For example, when the rear end 51c of the first medium 51 reaches the rear end alignment section 210a, the control section 250 slightly increases the height of the first rotation center 211e of the first drawing member 211. The force with which the first medium 51 is drawn by the first drawing member 211 is slightly weakened. This is the regulation of the first first pull-in operation. Therefore, it is possible to prevent the first drawing member 211 from drawing in the first medium 51 too much. Thereafter, the side edge alignment member 215 aligns the side edge of the first medium 51. When the side edges of the first medium 51 have been aligned and the first drawing member 211 has finished aligning the rear end 51c of the first medium 51 with the rear end alignment part 210a, the first drawing member 211 changes the attitude of the first retracting member 211 to the second attitude or the third attitude. This is the second regulation of the first pull-in operation.

- Instead of changing the attitude of the first drawing member 211 to the second attitude, a member is provided that presses the rear end portion of the second medium 52, and the member that presses the rear end portion of the second medium 52 is the second medium. The configuration may be such that the first drawing member 211 separates the medium 50 from the medium 50 while holding down the rear end portion of the medium 52 .

- The post-processing device 200 may not include the control section 250 and may be entirely controlled by the printing device control section 60.
- The control unit 250 may use the temperature and humidity of the environment in which the post-processing device 200 is installed. That is, the environmental sensor 61 may be included in the post-processing device 200.

- The printing device 13 and the post-processing device 200 may have an integrated housing instead of having separate housings.
- As information regarding the printing time of the medium 50, the printing device control unit 60 notifies the control unit 250 of the post-processing device 200 of the printing end time for the front side of the medium 50 and the printing end time for the back side of the medium 50. Good too. The control unit 250 can calculate the elapsed time from printing by estimating the time elapsed before the first retracting operation of the medium 50 in the post-processing device 200 and adding the elapsed time. The information is not limited to this, as long as the control unit 250 can calculate the elapsed time since printing.

- As information regarding the printing time of the medium 50, the printing device control unit 60 may notify the control unit 250 of the post-processing device 200 of the printing start time of the medium 50.
- The printing device control unit 60 does not need to notify the control unit 250 of the transport time of the medium 50 printed with the liquid discharged by the liquid discharge unit 27. The control unit 250 of the post-processing device 200 may calculate the transport time by the printing device control unit 60 notifying the control unit 250 of job details.

- The print duty may be notified by dividing the front and back sides of the medium 50 into a plurality of sections. In that case, the printing end time or printing start time at which each section was printed may be notified.

- As information regarding the printing time of the medium 50, the elapsed time from the end of printing on the front side of the medium 50 and the elapsed time from the end of printing on the back side of the medium 50 may be notified. The control unit 250 can calculate the elapsed time from printing by estimating the time elapsed before the first retracting operation of the medium 50 in the post-processing device 200 and adding the elapsed time.

- In this embodiment, the control unit 250 sets the front duty and the back duty when the length of the medium in the transport direction Y1 is short, and the contact part surface duty and the contact part duty when the length of the medium in the transport direction Y1 is long. Although the printing duty for both the entire medium surface of the medium 50 and the contact portion may be used. The contact portion surface duty and the contact portion back surface duty accurately reflect the frictional force F12. The front duty and the back duty accurately reflect the resistance force F13 and the falling force F14. By using both print duties, accurate control tables can be created, especially when the size of media 50 is large.

- The contact part duty may be the printing duty of the part that the first drawing member 211 contacts, or the printing duty of the part that the second drawing member 212 contacts.
- When the printing duty is high, the friction coefficient μ1b between the first medium 51 and the second medium 52 becomes high, making it difficult for the medium 50 to be drawn in. However, the medium 50 with a high printing duty requires high printing quality. No scratches from the first drawing member 211 are left on the surface of the medium 50. The height of the first retracting member 211 may be set higher than the standard, and instead, the rotation speed of the first retracting member 211 may be set even higher. Since it takes a long time to pull in the medium 50, productivity decreases, but it is possible to output high-quality printed matter.

- Although a control table is used in this embodiment, the first required number of rotations, the second required number of rotations, and the height when the first retracting member 211 is in the first posture can be determined by calculation formulas and conditional expressions using parameters as variables. You may also ask for the same.

- Since the first required rotation speed and the second required rotation speed vary depending on the type of medium 50, a plurality of control tables corresponding to typical types of medium are prepared, and a service person operates the operation unit 62. , the control table may be switched.

- A service person may connect a PC to the printing system 11, shift the printing system 11 to the repair mode by a special operation, and make changes in the repair mode.
- In this embodiment, the first required number of rotations of the first retracting member 211, the height when the first retracting member 211 is in the first posture, etc. are input and changed according to the result of the test process. . The first pull-in is determined by the printing duty of the medium 50, the basis weight and size of the medium 50, the number of sheets of the medium 50 loaded when the first pull-in member 211 performs the first pull-in operation of the medium 50 onto the intermediate tray 210, etc. A threshold value at which the first required number of rotations of the member 211 changes may be input. Similarly, a threshold value at which the height changes when the first retracting member 211 is in the first posture may be input.

- The post-processing device 200 may have a mechanism that allows a service person to change the height of the first retracting member 211.
Below, technical ideas and their effects understood from the above-described embodiments and modified examples will be described.

(A) The post-processing device includes a conveyance path that conveys a medium printed with a liquid discharged by a liquid discharge unit included in a printing device, an intermediate tray on which the medium conveyed by the conveyance path is loaded, and the intermediate tray. a first drawing member, which is provided on the tray and starts a first drawing operation of drawing the medium upstream in the transport direction after the rear end of the medium has passed through the transport path; a rear end aligning part that contacts a rear end of the medium drawn in by a first pulling member and aligns the rear end of the medium; and a control part that controls an operation of the first drawing member, the control part When the first cumulative number of rotations since the start of the first retraction operation reaches the first required number of rotations necessary for aligning the rear end of the medium with the rear end alignment part, The control unit is configured to restrict the first retraction operation, and the control unit determines the first required rotation speed according to parameter conditions.

According to this configuration, when the media printed by the liquid ejected by the liquid ejecting section are aligned, the medium drawn in by the first drawing member and the medium previously loaded on the intermediate tray are aligned in the intermediate tray. The frictional resistance between the two changes depending on the parameter conditions. Therefore, due to a change in the frictional resistance between the media, the time required for the rear end of the medium to reach the rear end alignment portion changes. Therefore, the control unit sets an appropriate first required rotation speed according to the parameter conditions. Therefore, when aligning media on the intermediate tray, the media may be misaligned due to the trailing edge of the media not reaching the trailing edge alignment section, or the media may be pulled in even after the trailing edge of the media reaches the trailing edge alignment section. Buckling of the medium caused by this can be suppressed.

(B) In the post-processing device, the control unit may control the temperature of the environment where the printing device is installed, the humidity of the environment where the printing device is installed, the size of the medium, the basis weight of the medium, the At least one of the number of media stacked on the intermediate tray may be used as the parameter.

According to this configuration, when the environmental temperature is low, the liquid adhering to the medium is difficult to dry, and the frictional resistance between the media becomes large. Furthermore, when the humidity of the environment is high, the liquid adhering to the medium is difficult to dry, and the frictional resistance between the media increases. Furthermore, the larger the size of the media, the larger the contact area between the media, which increases the frictional resistance when the media move. Moreover, since the weight of the medium is greater as the basis weight becomes larger, the frictional resistance between the media increases when the first drawing member pulls in the medium. The smaller the basis weight of the medium, the weaker the rigidity, so the medium is more likely to buckle. Furthermore, as the number of media stacked on the intermediate tray increases, the stacking height of the media bundle increases, and the media to be pulled in approaches the first pull-in member, and the first pull-in member pulls in the media. Since the pressing force sometimes increases, the frictional resistance between the media increases. The control unit determines the first required rotation speed according to at least one parameter among the following: environmental temperature, environmental humidity, medium size, medium basis weight, and the number of media loaded on the intermediate tray. change appropriately. Therefore, when aligning the media on the intermediate tray, it is possible to suppress irregularities in the media and buckling of the media.

(C) In the above-mentioned post-processing device, the control unit starts the first drawing operation in which the first drawing member draws the medium after printing on the medium is started by the liquid ejected by the liquid ejecting unit. the waiting time after printing on the medium printed with the liquid ejected by the liquid ejecting section, and the amount of liquid ejected per area of the liquid ejected onto the medium by the liquid ejecting section. At least one of them may be used as the parameter.

According to this configuration, the shorter the elapsed time from printing on the medium to the start of the first retraction operation, the longer the waiting time of the printed medium, and the larger the amount of liquid ejected per area, the more the medium The degree of dryness of liquid that has adhered to or penetrated tends to be low. If the degree of dryness of the liquid is low, the frictional resistance between the media will be large. The control unit appropriately changes the first required rotation speed according to at least one parameter among elapsed time, standby time, and liquid discharge amount per area. Therefore, when aligning the media on the intermediate tray, it is possible to suppress irregularities in the media and buckling of the media.

(D) In the post-processing device, the elapsed time includes a printing time on the medium printed with the liquid ejected by the liquid ejecting section, a transportation time on the medium printed with the liquid ejected by the liquid ejecting section, It may be at least one of the conveyance pitch time of the medium from the start of the first pull-in operation to the start of the next first pull-in operation.

According to this configuration, the shorter at least one of printing time, conveyance time, and conveyance pitch time is, the lower the degree of dryness of the medium is and the moisture content of the medium surface is still deteriorating, and the frictional resistance between the media is big. Therefore, the control unit can suppress unevenness of the medium and buckling of the medium by appropriately changing the first required rotation speed according to at least one parameter among printing time, conveyance time, and conveyance pitch time. .

(E) In the post-processing device, the control unit uses at least one of the waiting time, the amount of liquid discharged per area of the liquid, and the size of the medium as the parameter, and The first required number of rotations may increase as the number of rotations increases.

According to this configuration, when the standby time is long, it is necessary to ensure a long drying time for the medium, so the moisture content of the medium surface remains in a deteriorated state, and the frictional resistance between the media is large. Further, when the amount of liquid discharged per area is large, the water content of the medium surface is still in a deteriorated state, and the frictional resistance between the media is large. Furthermore, when the size of the medium is large, the contact area is large, so the frictional resistance is large. The control unit prevents unevenness of the medium and buckling of the medium by increasing the first required rotation speed as the numerical value of at least one of the waiting time, the amount of liquid discharged per area, and the size of the medium increases. It can be suppressed.

(F) In the above-mentioned post-processing device, the liquid ejection amount per area may be a contact portion duty in a region where the first drawing member contacts the medium or a region overlapping with the contact region.

According to this configuration, when the first drawing member draws in the medium, the ease with which the medium is drawn changes depending on the frictional resistance between the medium in the area that contacts the medium or the area that overlaps with the contact area. Rather than using the liquid discharge amount per area, it is better to use the contact part duty to reduce the frictional resistance between the media in the area that contacts the medium when the first drawing member draws in the medium, or the area that overlaps with the contact area. is reflected more accurately. Therefore, by the control section appropriately changing the first required rotation speed according to the contact portion duty, it is possible to suppress irregularities in the medium and buckling of the medium.

(G) In the post-processing device, the surface on the intermediate tray side when the medium is loaded on the intermediate tray is the back surface, and the first drawing member performs the first drawing operation on the medium as a first medium. In this case, the control unit may use a liquid ejection amount per area of the back surface of the first medium and a size of the first medium as the parameters.

According to this configuration, when the amount of liquid discharged per area is large, the frictional resistance between the media increases due to deterioration of the water content state of the media surface, and the force that brings the media into close contact increases. The amount of liquid ejected per area is the parameter that has the greatest influence on the state of the medium surface. When the size of the medium is large, the resistance when moving the medium increases. That is, even if the size of the medium changes, the control unit can suppress the occurrence of unevenness of the medium and buckling of the medium with a small number of parameters.

(H) In the post-processing device, the surface on the intermediate tray side when the medium is loaded on the intermediate tray is the back surface, and the first drawing member performs the first drawing operation on the medium as a first medium. In this case, the control unit may use, as the parameters, an amount of liquid ejected per area of the back surface of the first medium and humidity of an environment in which the printing apparatus is installed.

According to this configuration, when the amount of liquid discharged per area is large, the frictional resistance between the media increases due to deterioration of the water content state of the media surface, and the force that brings the media into close contact increases. The amount of liquid discharged per area is the parameter that has the greatest influence on the water content state of the medium surface. When the environmental humidity is high, the force that brings the media into close contact increases. That is, even if the environmental humidity changes, the control unit can suppress the occurrence of irregularities in the medium and buckling of the medium with a small number of parameters.

(I) In the above post-processing device, the medium has a surface opposite to a surface on the intermediate tray side when the medium is loaded on the intermediate tray, and the first drawing member performs the first drawing operation on the medium. is a first medium, and when the medium loaded on the top side of the intermediate tray when the first drawing member performs the first drawing operation is a second medium, the control unit: The amount of liquid ejected per area of the back surface of the first medium, the amount of liquid ejected per area of the surface of the second medium, the elapsed time of the back surface of the first medium, and the amount of liquid ejected per area of the back surface of the second medium. The elapsed time of the surface may be used as the parameter.

According to this configuration, the control unit is capable of controlling the condition between the water-containing state of the back surface of the first medium and the water-containing state of the surface of the second medium when the first drawing member performs the first drawing operation. Appropriate control according to the frictional resistance between media can suppress media misalignment and media buckling.

(J) In the above-mentioned post-processing device, when the posture in which the first pull-in member pulls in the first pull-in member is the first posture, the control unit controls the bottom surface of the intermediate tray on which the medium is loaded, and the bottom surface of the intermediate tray on which the medium is loaded; The height of the first retracting member, which is the distance between the center of rotation of the first retracting member and the rotation center of the first retracting member, may be determined according to the parameter conditions.

According to this configuration, the control unit can appropriately adjust the force for drawing the first medium by determining the height of the first drawing member in the first posture according to the parameter conditions. By appropriately determining the force for drawing the first medium, it is possible to suppress the occurrence of irregularities in the medium and buckling of the medium.

(K) In the above-mentioned post-processing device, the medium on which the first drawing member performs the first drawing operation is the first medium, and when the first drawing member performs the first drawing operation, the intermediate tray is When the medium loaded on the top side is the second medium, the control unit controls the first integrated rotation speed to With the first drawing member in contact with the first medium, the first drawing operation of the first drawing member is stopped, the height of the first drawing member is lowered, and the first drawing member is in contact with the second medium. may be changed to a second posture in which the medium is pressed down.

According to this configuration, the control unit generates a force for gripping the second medium by changing the attitude of the first drawing member to the second attitude, so that the first medium passes through the conveyance path. At times, the first medium can be restrained from moving the aligned second medium 52.

(L) In the above-mentioned post-processing device, the intermediate tray has a second drawing member provided downstream of the first drawing member in the transport direction, and the first drawing member draws in the first medium. When the posture is set to the first posture, the control unit may be configured such that when the first drawing member is in the second posture, the second drawing member is in a second posture that draws the first medium toward the upstream side in the conveying direction. By the time the retracting operation is started and the rear end of the first medium reaches the first retracting member, the first retracting member returns from the second attitude to the first attitude and restarts the first retracting operation. It may be configured to do so.

According to this configuration, the control unit suppresses movement of the aligned second medium by the first drawing member being in the second attitude, and suppresses movement of the first medium by the first attitude of the first drawing member. It is possible to achieve both consistency and consistency.

(M) In the above-mentioned post-processing device, when the first attitude in which the first drawing member draws in the first medium is the first attitude, when the first integrated number of rotations reaches the first required number of rotations, the The control unit may change the first drawing member from the first attitude to a third attitude in which the first drawing member is separated from the first medium.

According to this configuration, the control unit shortens the time during which the first drawing member is in contact with the surface of the first medium by changing the attitude of the first drawing member to the third attitude. 1. It is possible to make it difficult for the retracting member to have scratch marks, push marks, etc.

(N) In the above-mentioned post-processing device, the intermediate tray has a second retracting member provided downstream of the first retracting member in the conveying direction, and the control unit is configured such that the first retracting member is connected to the second retracting member. 3, the second drawing member starts a second drawing operation of drawing the first medium upstream in the conveying direction, and the rear end of the first medium reaches the first drawing member. By then, the first retracting member may be configured to return from the third attitude to the first attitude and resume the first retracting operation.

According to this configuration, the control unit suppresses rubbing marks and push marks on the second medium by the first drawing member being in the third attitude, and suppressing the first drawing by the first attitude of the first drawing member. It is possible to achieve both media matching.

(O) In the above-mentioned post-processing device, the control unit is configured such that a second cumulative number of rotations after the second drawing member starts the second drawing operation moves the rear end of the medium to the rear end alignment portion. The second retracting operation may be restricted when a second required rotational speed, which is the rotational speed necessary for alignment, is reached.

According to this configuration, the frictional resistance between the media changes depending on the parameters acquired from the printing device, and the time it takes for the trailing edge of the media to reach the trailing edge aligning section becomes longer. Set an appropriate second required rotation speed. Therefore, irregularities in the medium and buckling of the medium can be suppressed.

(P) The printing system includes a liquid ejection unit that ejects liquid onto a medium, a transport path that transports the medium printed with the liquid ejected by the liquid ejection unit, and the medium transported by the transport path is loaded. an intermediate tray, a first pulling member provided on the intermediate tray and configured to start a first pulling operation of pulling the medium upstream in the conveying direction after the rear end of the medium passes through the conveying path; and the intermediate tray. a trailing edge aligning part that is provided in the media and contacts the trailing end of the medium pulled in by the first pulling member to align the trailing end of the medium; and a control part that controls the operation of the first pulling member; and the control unit is configured such that a first cumulative number of rotations after starting the first retraction operation is a first necessary number of rotations necessary to align the rear end of the medium with the rear end alignment part. The control unit is configured to restrict the first retracting operation when the rotational speed is reached, and the control unit determines the first required rotational speed according to parameter conditions.

According to this configuration, the frictional resistance between the media changes depending on the parameters acquired from the printing device, and the time it takes for the trailing edge of the media to reach the trailing edge aligning section becomes longer. Set an appropriate first required rotation speed. Therefore, irregularities in the medium and buckling of the medium can be suppressed.

(Q) The printing system has a test mode for printing a test pattern for measuring the alignment accuracy of the trailing edge of the post-processed medium, and when the test mode is selected, prints the test pattern. The medium is configured to be capable of performing a test process, the medium on which the first drawing member performs the first drawing operation is the first medium, and the posture in which the first drawing member pulls in the first medium is a first posture. In this case, the control unit determines the first necessary number of rotations of the first retracting member and the height when the first retracting member is in the first attitude, depending on the result of the test process. At least one of them may be changeable.

According to this configuration, the service person changes at least one of the first necessary number of rotations of the first retracting member and the height when the first retracting member is in the first attitude, depending on the test result. By doing so, it is possible to suppress irregularities in the medium and buckling of the medium.

DESCRIPTION OF SYMBOLS 11... Printing system, 13... Printing device, 17... Conveyance path, 18... Conveyance motor, 19... Conveyance roller pair, 21... Cassette, 22... Pick-up roller, 23... Separation roller, 25... Support part, 26... Printing part, 27...Liquid discharge part, 50...Medium, 51...First medium, 51a...Surface of first medium, 51b...Back surface of first medium, 51c...Rear end of first medium, 51d...First medium Leading edge of the medium, 52...second medium, 52a...front surface of the second medium, 52b...back surface of the second medium, 52c...rear end of the second medium, 52d...leading edge of the second medium, 53... Third medium, 53a...Third medium surface, 53b...Third medium back surface, 53c...Third medium rear end, 53d...Third medium leading edge, 54...Fourth medium, 60 ...Printing device control unit, 61...Environmental sensor, 62...Operation unit, 64...Transport unit, 65...Transmission unit, 101...Ejection route, 102...Switchback route, 103...Reversing route, 104...Ejection unit, 200...Rear Processing device, 201... Acceptance roller pair, 201a... Acceptance drive roller, 201b... Acceptance driven roller, 202... Intermediate discharge roller pair, 202a... Intermediate tray discharge drive roller, 202b... Intermediate tray discharge driven roller, 203... Acceptance sensor, 204 ...Upper conveyance surface, 205...Lower conveyance surface, 206...Acceptance port, 207...Carry-in section, 208...Transport motor, 210...Intermediate tray, 210a...Rear end alignment section, 210b...Loading bottom surface, 211...First retracting member , 211a...first blade A, 211b...first blade B, 211c...first blade C, 211d...first core, 211e...first rotation center, 212...second retraction member, 212a...second blade A, 212b ...Second blade B, 212c...Second blade C, 212d...Second core, 212e...Second rotation center, 213...First rotation motor, 214...Second rotation motor, 215...Side end alignment member, 216...Medium Falling member, 229... Nip motor, 230... Ejection roller pair, 230a... Ejection driving roller, 230b... Ejection driven roller, 231... Ejection stacker, 232... Ejection motor, 233... Stacker motor, 234... Stacker height sensor, 235... Electric motor, 240... Post-processing mechanism, 250... Control section, 251... First current detection section, 252... Second current detection section, 253... First vertical movement motor, 254... First rotational position sensor, 255... Second Rotational position sensor, 256... Side edge alignment motor, 258... Side edge alignment position sensor, F11... Retraction force, F12... Friction force, F13... Resistance force, F14... Falling force, F15... Stopping force, F21... Retraction force, F22 ...Frictional force, F23...Resistance force, F24...Falling force, F31...Pushing force, F32...Resistance force, F33...Gripping force, N1...First rotation time, N2...Second rotation time, μ1a...First blade Friction coefficient with the first medium, μ1b...Friction coefficient between the first medium and second medium, μ2a...Friction coefficient between the second blade and the first medium, T1...First medium of the first blade T2...Press force of the second blade to the first medium, T3...Press force of the first medium to the second medium, θ...Angle of the intermediate tray from the horizontal, Δ1...The first medium Processing time, Δ2...Second processing time, NW...Network, W1...Rotation direction of the first drawing member, W2...Rotation direction of the second drawing member, X...Width direction, Y...Transportation direction, Y1...Transportation direction, Z ...Vertical direction.

Claims (14)

a conveyance path that conveys a medium printed with a liquid discharged by a liquid discharge unit included in the printing device;
an intermediate tray on which the medium transported by the transport path is loaded;
a first drawing member that is provided on the intermediate tray and starts a first drawing operation of drawing the medium upstream in the transport direction after the rear end of the medium passes through the transport path;
a trailing edge aligning part provided on the intermediate tray, contacting the trailing edge of the medium drawn in by the first drawing member, and aligning the trailing edge of the medium;
a control unit that controls the operation of the first retraction member;
The control unit controls the control unit when a first cumulative number of rotations after starting the first retraction operation reaches a first necessary number of rotations necessary for aligning the rear end of the medium with the rear end alignment unit. configured to regulate the first retraction operation,
The control unit determines the first required rotation speed according to parameter conditions ,
The control unit includes:
an elapsed time from when printing on the medium is started by the liquid discharged by the liquid discharge unit until the first pull-in member starts the first pull-in operation to pull the medium;
a standby time after printing on the medium printed with the liquid discharged by the liquid discharge unit;
a liquid discharge amount per area of the liquid discharged onto the medium by the liquid discharge section;
A post-processing device characterized in that at least one of the following is used as the parameter . The elapsed time is
printing time on the medium printed with the liquid discharged by the liquid discharge unit;
transport time for the medium printed with the liquid discharged by the liquid discharge unit;
a conveyance pitch time of the medium from starting the first pulling operation to starting the next first pulling operation;
The post-processing device according to claim 1 , wherein the post-processing device is at least one of the following. The control unit includes:
the waiting time;
liquid discharge amount per area of the liquid,
the size of the medium;
using at least one of the following as the parameter,
The post-processing device according to claim 1 , wherein the first required rotation speed increases as the numerical value of the parameter increases. The amount of liquid discharged per area is
The post-processing device according to claim 1 or 3, wherein the amount of liquid discharged is the amount of liquid discharged per area in a region where the first drawing member contacts the medium or a region overlapping with the contact region. The surface on the intermediate tray side when the medium is loaded on the intermediate tray is the back surface,
When the medium on which the first drawing member performs the first drawing operation is the first medium,
The control unit includes:
According to any one of claims 1 to 4 , the liquid discharge amount per area of the back surface of the first medium and the size of the first medium are used as the parameters. Post-processing equipment. The surface on the intermediate tray side when the medium is loaded on the intermediate tray is the back surface,
When the medium on which the first drawing member performs the first drawing operation is the first medium,
The control unit includes:
Any one of claims 1 to 4 , characterized in that the amount of liquid ejected per area of the back surface of the first medium and the humidity of the environment in which the printing device is installed are used as the parameters. The post-processing device according to item 1. a surface opposite to a surface on the intermediate tray side when the medium is loaded on the intermediate tray;
The medium on which the first drawing member performs the first drawing operation is a first medium;
When the first retracting member performs the first retracting operation, the medium loaded on the top side of the intermediate tray is a second medium;
The control unit includes:
a liquid ejection amount per area of the back surface of the first medium;
a liquid discharge amount per surface area of the second medium;
an elapsed time on the back side of the first medium;
elapsed time on the surface of the second medium;
The post-processing device according to any one of claims 1 to 4 , wherein: is used as the parameter. The medium on which the first drawing member performs the first drawing operation is a first medium;
When the posture in which the first drawing member draws in the first medium is the first posture,
The control unit may determine a height of the first drawing member, which is a distance between a bottom surface of the intermediate tray on which the medium is loaded and a rotation center of the first drawing member, according to the parameter conditions. The post-processing device according to any one of claims 1 to 7 , characterized in that: The medium on which the first drawing member performs the first drawing operation is a first medium;
When the first retracting member performs the first retracting operation, the medium loaded on the top side of the intermediate tray is a second medium;
The control unit controls the first retraction of the first retraction member in a state in which the first retraction member is in contact with the first medium when the first integrated rotational speed reaches the first required rotational speed. Claims 1 to 8 are characterized in that the operation is stopped, the height of the first retracting member is lowered, and the first position is changed to a second posture in which the second medium is pressed by the first retracting member. The post-processing device according to any one of the above. The intermediate tray includes a second pull-in member provided downstream of the first pull-in member in the conveyance direction,
When the posture in which the first drawing member draws in the first medium is a first posture,
The control unit causes the second retracting member to start a second retracting operation of pulling the first medium upstream in the transport direction when the first retracting member is in the second attitude;
The first drawing member is configured to return from the second attitude to the first attitude and restart the first drawing operation by the time the rear end of the first medium reaches the first drawing member. The post-processing device according to claim 9 , characterized in that: When the posture in which the first drawing member draws in the first medium is the first posture,
When the first integrated rotation speed reaches the first required rotation speed,
Any one of claims 1 to 8 , wherein the control unit changes the first drawing member from the first attitude to a third attitude in which the first drawing member is separated from the first medium. The post-processing device described in . The intermediate tray includes a second pull-in member provided downstream of the first pull-in member in the conveyance direction,
The control unit causes the second retracting member to start a second retracting operation of pulling the first medium upstream in the conveying direction when the first retracting member is in the third attitude;
By the time the trailing end of the first medium reaches the first retraction member, the first retraction member is configured to return from the third attitude to the first orientation and resume the first retraction operation. The post-processing device according to claim 11 . The control section is configured such that a second cumulative number of rotations after the second drawing member starts the second drawing operation is a number of rotations necessary for aligning the rear end of the medium with the rear end alignment section. The post-processing device according to claim 10 or 12 , wherein the post-processing device is configured to restrict the second retracting operation when a certain second required number of rotations is reached. a liquid ejection unit that ejects liquid onto a medium;
a conveyance path that conveys a medium printed with the liquid discharged by the liquid discharge unit;
an intermediate tray on which the medium transported by the transport path is loaded;
a first drawing member that is provided on the intermediate tray and starts a first drawing operation of drawing the medium upstream in the transport direction after the rear end of the medium passes through the transport path;
a trailing edge aligning part provided on the intermediate tray, contacting the trailing edge of the medium drawn in by the first drawing member, and aligning the trailing edge of the medium;
a control unit that controls the operation of the first retraction member;
The control unit controls the control unit when a first cumulative number of rotations after starting the first retraction operation reaches a first necessary number of rotations necessary for aligning the rear end of the medium with the rear end alignment unit. configured to regulate the first retraction operation,
The control unit is a printing system that determines the first required rotation speed according to parameter conditions,
The printing system has a test mode for printing a test pattern for measuring the alignment accuracy of the trailing edge of the post-processed medium,
configured to be able to perform a test process of printing the test pattern when the test mode is selected;
When the medium on which the first drawing member performs the first drawing operation is the first medium, and the posture in which the first drawing member draws the first medium is the first posture,
The control unit, depending on the result of the test process,
the first required rotation speed of the first retraction member;
a height when the first retracting member is in the first posture;
A printing system characterized in that at least one of the above can be changed .