JP7110833B2 - Inkjet printer, control method for inkjet printer - Google Patents

Description

The present invention relates to an inkjet printer and an inkjet printer control method.

Conventionally, in interrupting printing, if the amount of ink ejected up to the point of interruption exceeds a threshold value, it is determined that the paper should be ejected without being reversed, and the amount of ejected ink There is known a serial scan printer that determines to reverse when the value is equal to or lower than a threshold value, and performs a reverse operation or a paper ejection operation depending on either result (see, for example, Patent Document 1). .

JP 2007-152684 A

However, the ink-discharged portion of the paper tends to swell over time. Therefore, if the sheet is simply reversed and conveyed, the bulging portion of the sheet contacts the reversing mechanism and ink adheres to the reversing mechanism. In addition, there is a problem that the ink is transferred to the conveyed paper and the image quality is deteriorated.

An inkjet printer of the present application includes a transport section that transports a medium, an inkjet head that can eject ink onto the transported medium, and a control section that controls the transport section, wherein the control section controls the inkjet head positioning the retraction target portion of the medium in a correction region for correcting the attitude of the medium, which is a region different from the scanning region scanned by the inkjet head in the medium transport path when ejection of ink is interrupted by When the interrupted ink ejection is in the first mode, the retraction target portion is a portion located within the scanning area when the ink ejection is interrupted, and the interrupted ink ejection is performed in the first mode. In the second mode, in which the amount of ink ejected per predetermined area is smaller than that in the first mode, the retraction target portion includes the portion located within the scanning area when the ink ejection is interrupted and the portion upstream from the scanning area. and a portion located on the side.

In the inkjet printer described above, it is preferable that the correction area is located downstream of the scanning area in the transport path along which the medium is transported.

It is preferable that the correction area of the inkjet printer is a concave portion provided on the downstream side and recessed in the direction of gravity.

In the above ink jet printer, the correction area differs between the first mode and the second mode, and the correction area in the second mode is recessed in the direction of gravity. A recess is preferred.

In the inkjet printer, as the transport unit, a first paper discharge roller provided downstream of the scanning area in the transport path, and a first paper discharge roller provided downstream of the first paper discharge roller in the transport path, and a second paper discharge roller driven by the same drive source as the first paper discharge roller, wherein the transport amount of the medium per predetermined drive amount of the second paper discharge roller is greater than that of the first paper discharge roller. Largely, the correction area is preferably a speed increasing area between the first paper discharge roller and the second paper discharge roller in the transport path.

In the inkjet printer, the transport unit includes a first discharge roller provided downstream of the scanning area in the transport path, and a first discharge roller provided downstream of the first discharge roller in the transport path. and a second paper discharge roller driven by the same drive source as the first paper discharge roller, wherein the transport amount of the medium per predetermined drive amount of the second paper discharge roller is greater than that of the first paper discharge roller. In general, a region between the first discharge roller and the second discharge roller in the transport path is a speed increasing region, and the speed increases in the first mode and the second mode. Correction regions are different from each other, and the correction region in the first mode is preferably the acceleration region.

In the inkjet printer, the control unit positions the retraction target portion in the first mode in a first correction area as the correction area when in the first mode, and positions the retraction target portion in the first mode in the second mode. It is preferable that the retraction target part in the second mode is positioned in a second correction area upstream of the first correction area.

In the inkjet printer described above, it is preferable that the correction area is located upstream of the scanning area in a transport path along which the medium is transported.

A control method for an inkjet printer according to the present application is a control method for an inkjet printer including a transport unit that transports a medium, an inkjet head capable of ejecting ink onto the transported medium, and a control unit that controls the transport unit. wherein, when ink ejection by the inkjet head is interrupted, the retraction target portion of the medium is an area different from a scanning area scanned by the inkjet head in the conveying path, and is a correction area for correcting the posture of the medium. , and when the interrupted ink ejection is in the first mode, the retraction target portion is a portion located within the scanning area when the ink ejection is interrupted, and the interrupted ink ejection However, in the second mode, in which the amount of ink ejected per predetermined area is smaller than that in the first mode, the retraction target portion includes the portion located within the scanning area when the ink ejection is interrupted, and a portion positioned upstream from the scanning area.

1 is an external perspective view showing the configuration of a printer; FIG. 1 is a schematic diagram showing the configuration of a printer; FIG. FIG. 2 is a plan view showing the configuration of the head; FIG. 4 is a detailed diagram showing the configuration around the conveying unit; FIG. 2 is a block diagram showing the control configuration of the printer; 4A and 4B are schematic diagrams for explaining print modes of a printer; FIG. 4A and 4B are schematic diagrams for explaining print modes of a printer; FIG. FIG. 4 is an explanatory diagram showing an example of the state of a medium when ink ejection is interrupted; The schematic diagram for demonstrating a correction area|region. FIG. 4 is an operation diagram for explaining a printer control method; FIG. 4 is an operation diagram for explaining a printer control method; FIG. 4 is an operation diagram for explaining a printer control method; FIG. 4 is an operation diagram for explaining a printer control method; FIG. 5 is a partial schematic diagram showing the configuration of a printer according to Modification 1;

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

(First embodiment)
First, the configuration of the printer 1 will be described.
FIG. 1 is an external perspective view showing the configuration of the printer 1. As shown in FIG. In the following description, assuming that the printer 1 shown in FIG. 1 is placed on a horizontal plane, the vertical direction along the upward and downward directions is defined as the Z-axis direction, and the directions along the horizontal plane are defined as the X-axis direction and the Y-axis direction. . In this embodiment, the width direction of the printer 1 is the X-axis direction, the depth direction is the Y-axis direction, and the height direction is the Z-axis direction. The X-axis direction, the Y-axis direction, and the Z-axis direction are different directions, and are orthogonal to each other.

As shown in FIG. 1, the printer 1 is a printer capable of forming an image on a sheet S as a medium. The printer 1 can form an image on roll paper of a relatively large size such as JIS standard A0 size or B1 size as the paper S, for example. In addition, the printer 1 can also form an image on a sheet of paper S such as A4 size. The printer 1 includes a main body portion 2 and a discharged paper receiving portion 3 . The main body part 2 is provided on the upper part of the support 8 erected on the base 9 . The discharged paper receiving section 3 has a paper collecting section 4 . The paper collecting section 4 is provided below the main body 2 and receives the paper S ejected from the main body 2 side. The main component of the paper S of this embodiment is wood fiber.

A main unit 2 of the printer 1 includes a substantially rectangular parallelepiped housing 12 . A paper feed cover 13 positioned on the rear side and a maintenance cover 14 positioned on the front side are provided on the upper surface of the housing 12 so as to be able to be opened and closed. An operation panel 15 for performing various operations of the printer 1 is provided at a position adjacent to the maintenance cover 14 in the X-axis direction on the upper surface of the housing 12 . A discharge port 16 is provided on the front surface of the housing 12, which is the side surface on the +Y direction side in the Y-axis direction. The sheet S on which an image has been formed in the housing 12 is discharged from the discharge port 16 toward the +Y direction side (forward). A paper ejection section 90 that supports the paper S ejected from the paper ejection port 16 is provided on the front surface of the housing 12 . The printer 1 also includes a control section 60 that controls each section.

Next, the internal structure of the printer 1 will be described.
FIG. 2 is a schematic diagram showing the configuration of the printer 1. As shown in FIG. FIG. 3 is a plan view showing the configuration of the head 21. As shown in FIG. The head 21 is an inkjet head.
As shown in FIG. 2, the printer 1 has a guide shaft 32 extending in the X-axis direction inside the housing 12 . The guide shaft 32 is installed at a predetermined height position in the Z-axis direction inside the housing 12 while being supported by the frame 18 . A rail portion 33 extending in the X-axis direction is provided at a height position above the guide shaft 32 . The rail portion 33 is formed by bending a portion of the frame 18 and functions as a support shaft together with the guide shaft 32 . The carriage 20 is guided by the guide shaft 32 and the rail portion 33 and is movable in the X-axis direction, which is the extending direction of the guide shaft 32 . The head 21 is supported by the carriage 20 and reciprocates along with the carriage 20 in the X-axis direction. The head 21 has a nozzle surface 21A in which nozzles N for ejecting ink as liquid are opened.

As shown in FIG. 3, a nozzle surface 21A of the head 21 is provided with a plurality of nozzles N. As shown in FIG. The head 21 is provided with an actuator (not shown) corresponding to each nozzle N, and by driving the actuator, ink can be ejected from each nozzle N as droplets. A piezoelectric element, for example, can be employed as the actuator. The nozzles N form a nozzle row NR arranged in the Y-axis direction. The nozzle row NR is composed of a group of M nozzles N arranged at a predetermined pitch in the Y-axis direction. M is a predetermined value within the range of 100-500, for example. A plurality of nozzle rows NR are arranged in parallel in the X-axis direction.
Here, the dimension in the transport direction Y of the range in which the plurality of nozzles N constituting the nozzle row NR are formed is defined as the nozzle row dimension NL. Then, when the head 21 moves in the X-axis direction as the width direction, the scanning region E is a portion where the nozzle row dimension NL and the paper S overlap when viewed from the +Z direction.

Returning to FIG. 2 , the printer 1 has a moving mechanism 22 that moves the carriage 20 . The moving mechanism 22 includes a guide shaft 32 and a rail portion 33 that support the carriage 20, a carriage motor 23 that is a power source of the carriage 20, and a timing belt 25 that is wound around a pulley 24 that rotates with the power of the carriage motor 23. etc. The carriage 20 is fixed to a part of the timing belt 25 and reciprocates in the X-axis direction by driving the carriage motor 23 forward and backward. The printer 1 also includes a first encoder 26 for detecting the movement position of the carriage 20 in the X-axis direction, which is the scanning direction. The carriage 20 is speed-controlled and position-controlled based on the pulse signal output from the first encoder 26 .

An ink cartridge 27 is detachably attached to the carriage 20 . The ink cartridge 27 is an example of an ink containing body that contains ink to be supplied to the head 21 . The carriage 20 carries the ink cartridge 27 and the head 21 and moves in the X-axis direction as the scanning direction. The ink cartridge 27 is mounted on the carriage 20 at a position in the +Z direction from the head 21 . The carriage 20 has a main body 20A that can accommodate the ink cartridges 27, and a cover 20B that covers the ink cartridges 27 accommodated in the main body 20A from above. A plurality of ink cartridges 27 each containing ink of a plurality of colors including four colors of cyan, magenta, yellow, and black, for example, are mounted. Note that, for example, only one black ink cartridge 27 may be installed.

The carriage 20 has terminals (not shown) on the mounting surface of the ink cartridge 27 . The terminal is electrically connected to the control unit 60 . The ink cartridge 27 mounts a memory element and has a terminal on the mounting surface. When the ink cartridge 27 is detached from the carriage 20, both terminals are separated and are in an electrically non-contact state. The control unit 60 detects attachment and detachment of the ink cartridge 27 through connection and disconnection of both terminals of the ink cartridge 27 and the carriage 20 . Further, the control unit 60 can read and write data to and from the memory element through the connection of both terminals while the ink cartridge 27 is attached to the carriage 20 . The storage element of the ink cartridge 27 stores ink-related information such as product number information, ink color information, remaining ink amount information, and the like.
The control unit 60 manages the amount of ink consumed by the printer 1 for printing and the like, and manages the current remaining amount of ink by subtracting the amount of ink consumption from the remaining amount information read from the storage element. When the power of the printer 1 is turned on, the remaining amount of ink is read out from the storage element, and when the power of the printer 1 is turned off, the information on the remaining amount of ink measured so far is written in the storage element.
Then, for example, when the remaining amount of ink in the ink cartridge 27 reaches a predetermined value, the control unit 60 causes the operation panel 15 to display a message suggesting replacement of the ink cartridge 27 . Further, the control unit 60 stops ejection of ink from the head 21 .
The ink cartridge 27 can be attached and detached by opening the maintenance cover 14 .
In the embodiment, the configuration in which the ink cartridge 27 is replaced with a new ink cartridge 27 when the remaining amount of ink in the ink cartridge 27 reaches a predetermined value has been described as an example. The ink cartridge 27 may be replenished with ink when the remaining amount of ink reaches a predetermined value.

The printer 1 includes a feeding section 35 that feeds the paper S. As shown in FIG. The feeding unit 35 includes a rotatable feeding shaft 36 on which a roll body R formed by cylindrically winding the paper S can be loaded. A feeding motor 37, which is a power source of the feeding shaft 36, is driven to rotate the roll body R counterclockwise in FIG. The paper S delivered from the roll body R is continuous paper. Feed motor 37 is shown in FIG. The feeding unit 35 can also feed, for example, cut-sheet paper S through the supply port 17, as indicated by a two-dot chain line in FIG.
The sheet S unwound from the roll body R is conveyed along the conveying path V formed along the conveying section 40 .

The paper S fed out from the roll body R passes along the path forming member 19, which has a curved upstream portion of the transport path V and a horizontally extending downstream portion, toward the head 21. be guided towards. After passing between the head 21 and the medium support unit 30 , the sheet S is conveyed downstream by the conveying unit 40 , passes through the discharge port 16 opened in the front surface of the housing 12 , and exits from the housing 12 to the housing 12 . discharged to the outside. That is, in the present embodiment, among the directions along the Y-axis, the direction from the rear to the front of the housing 12, or the direction from the right to the left in FIG. It becomes the conveying direction Y.

The medium support section 30 is arranged to face the nozzle surface 21A of the head 21 . The medium support section 30 has a surface that faces the head 21 and supports the paper S. As shown in FIG.

A pressing roller 31 is rotatably arranged at a position in the +Z direction of the medium support section 30 on the downstream side of the transport path V from the head 21 . When the paper S printed by the head 21 is supported by the medium support section 30 and transported to the downstream side of the transport path V, the pressure roller 31 contacts the surface of the paper S to which the ink is adhered. Therefore, the pressing roller 31 is configured with a star wheel or the like having a small contact area with the paper S in order to reduce deterioration of the quality of the image printed on the paper S. As shown in FIG.

The transport unit 40 transports the paper S drawn out from the roll body R along the transport path V passing between the head 21 and the medium support unit 30 and through the medium cutting unit 50 from the inside of the housing 12 to the paper discharge port. Transport to 16. On the downstream side of the medium support section 30, a first roller pair 41 including a driving roller 45 as a first paper discharge roller and a It has a plurality of roller pairs of a second roller pair 42 including a drive roller 45 and a third roller pair 43 . On the other hand, one roller pair 44 is provided on the upstream side of the medium support section 30 .

The first roller pair 41, the second roller pair 42, the third roller pair 43, and the roller pair 44 are a drive roller 45 and a drive roller 45 that can be driven and rotated by a conveyance motor 39 (see FIG. 5) as the same drive source. It is composed of a driven roller 46 capable of being driven to rotate with respect to the rotation of 45 . The first roller pair 41, the second roller pair 42, the third roller pair 43, and the roller pair 44 transport the paper S by rotating with the paper S sandwiched between the driving roller 45 and the driven roller 46. . The drive roller 45 is arranged to contact the paper S from the -Z direction, and the driven roller 46 is arranged to contact the paper S from the +Z direction.
Further, the transport section 40 is provided with a second encoder 58 that detects the operation of the transport motor 39 . A second encoder 58 is shown in FIG.

The driven rollers 46 of the first roller pair 41, the second roller pair 42, and the third roller pair 43 come into contact with the surface of the printed paper S to which printing ink is adhered when the paper S is transported. Therefore, the driven rollers 46 of the first roller pair 41, the second roller pair 42, and the third roller pair 43 are configured by star wheels or the like having a small contact area with the paper S. As shown in FIG. A plurality of the pressing rollers 31, the downstream first roller pair 41, the second roller pair 42, the third roller pair 43, and the roller pair 44 are arranged at predetermined intervals in the X-axis direction.
Further, when the transport motor 39 that drives each drive roller 45 is driven by a predetermined drive amount, the transport amount of the paper S in each drive roller 45 is determined by the gear ratio of the transmission gear connected between the drive rollers 45. Also, it is appropriately set depending on the diameter of each drive roller 45 and the like. In the present embodiment, when the paper S is transported in the transport direction Y, the transport amount of the paper S by each driving roller 45 in the first roller pair 41, the second roller pair 42, and the third roller pair 43 is It is larger than the transport amount of the driving rollers 45 of the pair 44 . In other words, each driving roller 45 in the first roller pair 41, the second roller pair 42, and the third roller pair 43 is in a state of being accelerated with respect to the driving roller 45 of the roller pair 44 on the upstream side.

That is, when ink is ejected from the head 21 onto the paper S to form an image, the paper S is likely to swell and deform due to the reception of the ink. In particular, when the paper S is deformed in the scanning area E of the head 21 , the deformed portion of the paper S comes into contact with the head 21 , causing staining of the paper S and ejection failure of the head 21 . Therefore, in the present embodiment, the driving rollers 45 of the first roller pair 41, the second roller pair 42, and the third roller pair 43 are arranged downstream of the medium support section 30 including the scanning area E in the transport direction Y. is larger than the driving roller 45 of the roller pair 44, tension is applied to the paper S. As a result, it is possible to reduce the occurrence of deformation of the paper S in the scanning area E, and prevent the occurrence of ejection defects. Note that the deformation of the paper S due to the reception of ink tends to occur in the scanning area E where the ink is ejected. This is because the deformation of the paper S due to the reception of ink is more likely to occur as the amount of water contained in the paper S increases, and after the amount of deformation of the paper S reaches its peak, the more time elapses after the ink is ejected, the more This is because evaporation of water from the paper S progresses.
Further, in the present embodiment, when the paper S is transported in the transport direction Y, the transport amount of the paper S per predetermined drive amount of the drive rollers 45 of the second roller pair 42 is determined by driving the first roller pair 41. It is configured to be larger than the conveying amount of the roller 45 . For example, it is set by the gear ratio of the transmission gear, the diameter of each drive roller 45, and the like. Therefore, the area between the first roller pair 41 and the second roller pair 42 becomes a speed increasing region.
A detailed configuration around the transport unit 40 will be described later.

The medium cutting unit 50 is arranged in the transport direction Y between the second roller pair 42 and the third roller pair 43 . The medium cutting unit 50 is composed of a disk-shaped drive blade 51 driven and rotated about an axis extending in the horizontal direction and a disk-shaped driven blade 52 driven to rotate. The drive blade 51 and the driven blade 52 are positioned below the driven blade 52 in the vertical direction Z. As shown in FIG. The cutting edge that forms the upper portion of the drive blade 51 and the cutting edge that forms the lower portion of the driven blade 52 are arranged so as to overlap each other.

Therefore, between the second roller pair 42 and the third roller pair 43, the driving blade 51 and the driven blade 52 scan the paper S in the X-axis direction, which is the width direction intersecting the conveying direction Y of the paper S. is disconnected by Then, the paper S cut by the medium cutting section 50 is discharged from the paper discharge port 16 by being conveyed downstream by the third roller pair 43 . The paper S ejected from the paper ejection port 16 is accommodated in the paper collection section 4 . Note that the printer 1 according to the present embodiment is designed so that the user cannot insert his or her fingertips from the outside of the housing 12 through the paper discharge port 16 into the movable portion such as the medium cutting section 50 inside the housing 12 . , the interval in the Z-axis direction at the opening of the paper ejection port 16 is relatively small.

Next, a detailed configuration around the transport unit 40 will be described. FIG. 4 is a detailed diagram showing the configuration around the transport section 40. As shown in FIG.
As shown in FIG. 4 , in the first roller pair 41 , the axial center of the drive roller 45 is positioned downstream of the axial center of the driven roller 46 by a distance d1 in the transport direction Y. As shown in FIG. Similarly, in the second roller pair 42 as well, the axial center of the drive roller 45 is located downstream of the axial center of the driven roller 46 by a distance d2 in the transport direction Y. The sandwiching position P1 of the sheet S by the first roller pair 41 is positioned in the +Z direction from the support position P of the sheet S by the medium support section 30 . Further, the sandwiching position P2 of the paper S between the second roller pair 42 is positioned in the +Z direction from the sandwiching position P1 of the paper S between the first roller pair 41 . In the present embodiment, the pinching position by each roller pair means a line segment connecting the centers of the two roller shafts constituting the roller pair on a plane extending in the Y-axis direction and the Z-axis direction as shown in FIG. and the outer peripheries of the two rollers.

Therefore, when the sheet S sandwiched between the first roller pair 41 and the second roller pair 42 is conveyed downstream along the conveying path V, the conveying direction is the horizontal first direction D1. , to a second direction D2 that intersects with the first direction D1 and that is diagonally upward toward the downstream side. In the present embodiment, the first roller pair 41 and the second roller pair 42 change the direction in which the sheet S is transported from the first direction D1 to the first direction on the downstream side of the transport path V from the medium support section 30. The paper S is guided downstream by changing to a second direction D2 that intersects with D1.

On the other hand, as shown in FIG. 4 , in the third roller pair 43 , the axial center of the drive roller 45 is positioned upstream of the axial center of the driven roller 46 by a distance d3 in the transport direction Y. The position P3 of the paper S between the third roller pair 43 and the position P1 of the paper S between the first roller pair 41 is positioned in the -Z direction. Furthermore, the sandwiching position P3 of the paper S by the third roller pair 43 is positioned in the −Z direction from the support position P of the paper S by the medium support section 30 .

Therefore, when the sheet S is conveyed downstream along the conveying path V in a state of being sandwiched between the second roller pair 42 and the third roller pair 43, the direction in which the sheet S is conveyed is the oblique upward direction toward the downstream side. It changes from the second direction D2 to a third direction D3 that intersects with the second direction D2 and is diagonally downward toward the downstream side.

As shown in FIG. 4, a support member 47 is arranged between the first roller pair 41 and the second roller pair 42 to support the paper S by contacting the paper S from the -Z direction. be. The support member 47 contacts the sheet S conveyed downstream in the second direction, which is the obliquely upward direction, while being sandwiched between the first roller pair 41 and the second roller pair 42 . The surface of the support member 47 that supports the sheet S extends downstream in a second direction D2 that is obliquely upward. Therefore, the sheet S sandwiched between the first roller pair 41 and the second roller pair 42 constituting the transport unit 40 and transported in the second direction D2 has a stable transport posture.

Further, as shown in FIG. 4, a position upstream of the medium cutting unit 50 between the second roller pair 42 and the third roller pair 43 is in contact with the paper S from the -Z direction. A support member 48 capable of supporting the sheet S is arranged. The support member 48 contacts the sheet S sandwiched between the second roller pair 42 and the third roller pair 43 and conveyed downstream in a third direction D3, which is an oblique downward direction. The surface of the support member 48 that supports the sheet S extends downstream in a third direction D3 obliquely downward. Therefore, the sheet S sandwiched between the second roller pair 42 and the third roller pair 43 and transported in the third direction D3 has a stable transport attitude.

Here, as shown in FIG. 4 , a first straight line L1 extending in a first horizontal direction D1 and a second straight line L2 extending in a second direction D2 diagonally upward toward the downstream side of the recess 100 The pressure roller 31 provided in the +Z direction intersects at the -Z direction end position Pa. Further, a second straight line L2 extending downstream in a second direction D2 that is an obliquely upward direction and a third straight line L3 that extends downstream in a third direction D3 that is an obliquely downward direction are defined by the second roller pair . S intersects at sandwiching position P2.

In this case, the angle θA formed by the second straight line L2 intersecting the first straight line L1 toward the downstream side of the conveying path V is positive with respect to the first straight line in the vertical direction Z. is an angle with an angle in the +Z direction. On the other hand, the angle θB formed by the third straight line L3 intersecting the first straight line L1 toward the downstream side of the transport path V is negative with respect to the first straight line in the vertical direction Z— A corner with an angle in the Z direction. That is, the second straight line L2 intersects the first straight line L1 and forms an angle θA toward the downstream side of the transport path V, and the third straight line L3 intersects the first straight line L1 and forms an angle θA toward the downstream side of the transport path. The positive/negative direction of the angle θB with respect to the first straight line L1 is different from the angle θB formed toward . Therefore, in the housing 12, when viewed from the width direction X, the transport path V of the sheet S from the medium support section 30 to the discharge port 16 is +Z direction and -Z direction in the vertical direction Z. It is configured to change the conveying direction alternately with the direction. In the present embodiment, the angle formed by two straight lines toward the downstream side of the conveying path V is an angle formed by a portion of a half straight line extending downstream in the conveying direction Y from the intersection of the two straight lines. be.

In addition, the positional relationship in the transport direction Y between the center of the axis of the drive roller 45 and the center of the axis of the driven roller 46 is appropriately changed according to the inclination of the transport path V with respect to the horizontal direction. That is, since the direction in which the paper S is conveyed changes, the position in the conveying direction Y between the center of the axis of the driving roller 45 and the center of the axis of the driven roller 46, and the distances d1, d2, and d3 are the same as the conveying path V is changed as appropriate according to the inclination with respect to the horizontal direction.

Further, a concave portion 100 is provided on the downstream side of the scanning area E scanned by the head 21 . In this embodiment, the recess 100 is provided in the medium support portion 30 . More specifically, the recess 100 is formed in the medium support section 30 toward the −Z direction from the support surface including the support position P where the sheet S is supported. The concave portion 100 is provided in the −Z direction of the pressing roller 31 . The recessed portion 100 is recessed in the direction of gravity and formed over the entire width direction of the medium support portion 30 in the X-axis direction.
The concave portion 100 moves the leading end portion of the sheet S on the downstream side in the -Z direction. Specifically, since the downstream edge of the paper S fed out from the roll body R is curled, when the paper S is positioned on the medium support section 30, the downstream edge of the paper S is bent. is likely to float in the +Z direction, and the posture of the sheet S on the medium support section 30 is not stable. Therefore, by positioning the leading edge of the sheet S on the downstream side in the concave portion 100, the leading edge of the sheet S moves in the -Z direction, thereby preventing the sheet S from floating. The concave portion 100 of this embodiment also functions as a correction area Q (see FIG. 9), which will be described later.

Next, the control configuration of the printer 1 will be explained.
FIG. 5 is a block diagram showing the control configuration of the printer 1. As shown in FIG.
As shown in FIG. 5, the printer 1 prints an image on a sheet S based on print data received from a host device (not shown). The printer 1 includes a control section 60 that controls the carriage 20, the transport section 40, and the like.
The head 21 , the carriage motor 23 , the feed motor 37 and the transport motor 39 are electrically connected to the controller 60 . In addition, the control unit 60 includes the operation panel 15, a cover sensor 57 that detects opening and closing of the maintenance cover 14, a first encoder 26, a second encoder 58, a medium detector 59 provided in the transport path V of the paper S, and an ink detector 59. A memory element provided in the cartridge 27 is connected.

The control unit 60 causes ink to be ejected from the nozzles N by controlling the head 21 based on the print data. The control unit 60 also controls the carriage motor 23 to perform position control and speed control of the carriage 20 . The controller 60 rotates the carriage motor 23 in the forward direction to move the carriage 20 forward from the -X direction to the +X direction, and rotates the carriage motor 23 in the reverse direction to move the carriage 20 from the +X direction to the -X direction. Move back towards the direction. Further, the control unit 60 controls the feeding motor 37 to rotate the feeding shaft 36 to let out the roll body R and feed the sheet S to the head 21 side. In addition, the control unit 60 controls the transport motor 39 to drive the driving rollers 45 of the transport unit 40 so that the roller pair 44, the first roller pair 41, the second roller pair 42, and the third roller pair 43 The fed sheet S is transported in the transport direction Y.

The control unit 60 causes the operation panel 15 to display various menus and various messages. The control unit 60 manages the amount of ink remaining in the ink cartridge 27 via a memory element, and determines whether or not the amount of ink remaining in the ink cartridge 27 has reached a predetermined value. When the control unit 60 determines that the remaining amount of ink has reached a predetermined value, that is, when it determines that the ink has reached the end, it displays a message to the effect that the ink has run out on the operation panel 15 to notify the user. inform.

After notifying that the ink has run out, the control unit 60 inputs a detection signal from the cover sensor 57 that detects that the user has opened the maintenance cover 14 while the ink end flag is set in the memory 65. It is recognized that the ink cartridge 27 has been replaced.

The control unit 60 includes a CPU 61 , a first counter 62 , a second counter 63 and a memory 65 . Various programs executed by the CPU 61 are stored in the memory 65 . The programs include an ink cartridge replacement control program for replacing the ink cartridge 27, a print control program for print processing, and the like. The CPU 61 performs various print controls by executing print control programs stored in the memory 65 . Further, the CPU 61 performs control when replacing the ink cartridge 27 by executing an ink cartridge replacement control program. Here, the control at the time of replacement of the ink cartridge 27 means to support the replacement of the ink cartridge 27 by the user, and to suppress deterioration of print quality due to interruption of printing when replacement of the ink cartridge 27 is performed during printing. control. The control for replacing the ink cartridge 27 includes control for moving the carriage 20 to a predetermined position where the ink cartridge 27 is replaced, control for retracting the sheet S, and the like.

The first counter 62 acquires a count value indicating the carriage position by counting the number of pulse edges of the pulse signal from the first encoder 26 with the home position of the carriage 20 as the origin under the instruction of the CPU 61 . Specifically, the control unit 60 acquires the moving direction of the carriage 20 by comparing two phases included in the pulse signal from the first encoder 26 . Then, every time a pulse edge is detected in the input signal from the first encoder 26, the control unit 60 increments the count value of the first counter 62 in the forward movement direction (+X direction) moving away from the home position. , the count value of the first counter 62 is decremented in the backward movement direction (-X direction).

The second counter 63 is instructed by the CPU 61 to count the number of pulse edges of the pulse signal from the second encoder 58 with the position where the medium detector 59 on the transport path V detects the paper S as the origin position. A count value indicating the transport position of the sheet S is obtained. More specifically, the control unit 60 obtains the rotation direction of the transport motor 39 based on the pulse signal from the second encoder 58, and detects the pulse edge of the pulse signal. The count value is incremented, and if it is in the reverse direction, the count value of the second counter 63 is decremented.

Here, the print control executed by the print control program is control for printing an image on the paper S based on the print data received from the host device. In this embodiment, the head 21, the transport motor 39, etc. are controlled based on the print mode included in the print data.
The print mode is set according to the amount of ink ejected per predetermined area of the paper S when ink is ejected onto the paper S from the head 21 . The print mode of this embodiment has a first mode and a second mode.
The second mode is ink ejection in which the amount of ink ejected per predetermined area of the sheet S is smaller than that in the first mode. In other words, the first mode is a print mode for high-quality printing, and the second mode is a print mode for high-speed printing.

When printing, the controller 60 causes the carriage 20 to move the head 21 in the X-axis direction, which is the main scanning direction, while ejecting ink from the nozzles N toward the paper S. FIG. This operation is called a "pass". As a result, a raster line, which is a row of dots d formed along the main scanning direction, is printed on the paper S. FIG. Next, the controller 60 drives the transport motor 39 to transport the paper S in the +Y direction as the sub-scanning direction. By repeating the above operation by the control unit 60, rows of dots d are arranged in the sub-scanning direction of the paper S, and an image is formed on the paper S. FIG.
Here, when printing at a resolution exceeding the interval between adjacent nozzles N, after printing one raster line, the paper S is slightly fed and the carriage 20 is scanned several times so as to reach the desired resolution. Then, when the desired resolution is reached, the process of moving to the next cycle is repeated.

As a specific example, a case where an image is printed by scanning the carriage 20 four times in the first mode and an image is printed by scanning the carriage 20 twice in the second mode will be described below. In other words, the first mode is four-pass printing and the second mode is two-pass printing. In the first mode, dots d are formed by feeding the paper S by a feed amount smaller than the feed amount of the paper S after two passes in the second mode. Therefore, in the first mode, the amount of ink ejected per predetermined area of the paper S is greater than in the second mode, and high-quality printing can be performed. On the other hand, in the second mode, since the paper S is sent by a larger feed amount than in the first mode every two passes, high-speed printing can be performed.

6 and 7 are schematic diagrams for explaining print modes of the printer 1. FIG. Specifically, FIG. 6 is a schematic diagram for explaining the first mode, and FIG. 7 is a schematic diagram for explaining the second mode. 6 and 7, the nozzle surface 21A of the head 21 and the width direction X of the paper S are shown side by side for ease of explanation. Also, the number of nozzles N in the head 21 is made smaller than the actual number. Also, although the paper S is actually moved in the transport direction Y with respect to the head 21, the state in which the head 21 is moved with respect to the paper S is shown.

As shown in FIG. 6, in the first mode, the head 21 moves the sheet S in the +Y direction at the same pitch each time. In the present embodiment, when the pitch dimension between adjacent nozzles N is divided by 1/4, the paper S is moved by a dimension distance corresponding to 5/4 pitch. As a result, the nozzle N of the next pass moves to a position parallel to the nozzle N of the previous pass in the Y-axis direction. As a result, the raster lines of the first pass and the raster lines of the second pass are formed adjacent to each other. Similarly, the raster lines of the third pass are formed adjacent to the raster lines of the second pass. Then, the raster lines of the fourth pass are formed adjacent to the raster lines of the third pass. Also, the raster lines of the fourth pass are formed adjacent to the raster lines of the first pass. As a result, all raster lines are formed.
Note that the area where the image is completed is referred to as a first area F1.

Further, of the raster lines formed from the second pass, the second region F2, which is a part of the upstream side in the transport direction, is in a state in which a non-dot region is formed in which one more raster line is not formed. , the image formation is completed when the raster line of the fifth pass (not shown) is formed in the non-dot area.
Further, of the raster lines formed from the third pass, the third region F3, which is a part of the upstream side in the transport direction, is in a state in which a non-dot region in which two more raster lines are not formed is formed. , image formation is completed when the raster lines of the 5th and 6th passes (not shown) are formed in the non-dot areas.
Further, of the raster lines formed from the fourth pass, the fourth region F4, which is a part of the upstream side in the transport direction, is in a state in which a non-dot region is formed in which three more raster lines are not formed. , the image formation is completed when the raster lines of the 5th, 6th, and 7th passes (not shown) are formed in the non-dot areas.
Here, the amount of ink ejected per predetermined area of the sheet S differs in each area from the first area F1 to the fourth area F4. Specifically, the amount of ink ejected per predetermined area of the sheet S in the first area F1 is larger than that in the second area F2. The ejection amount of ink per predetermined area of the sheet S in the second area F2 is larger than that in the third area F3. The ejection amount of ink per predetermined area of the sheet S in the third area F3 is larger than that in the fourth area F4. Therefore, a gradient of the ink ejection amount is formed from the first area F1 toward the fourth area F4, and the ink ejection amount per predetermined area of the sheet S gradually decreases.

As shown in FIG. 7, in the second mode, after the raster lines are formed in the first pass, the paper S is moved in the +Y direction with respect to the head 21 . In the present embodiment, in the second pass, when the pitch dimension between adjacent nozzles N is divided by 1/2, the paper S is moved by a dimension distance corresponding to 1/2 pitch. As a result, the raster lines of the first pass and the raster lines of the second pass are formed in parallel. Then, all raster lines are formed.
Note that the area where the image is completed is referred to as a first area G1.

In addition, the second region G2, which is the region in which the new first pass is formed, is in a state where a non-dot region is formed in which five raster lines are not formed, and the raster lines in the second pass are formed as described above. Image formation is completed when the dots are formed in the non-dot areas.
Here, the amount of ink ejected per predetermined area of the sheet S differs between the first area G1 and the second area G2. Specifically, the amount of ink ejected per predetermined area of the sheet S in the first region G1 is larger than that in the second region G2. Therefore, a gradient of the ink ejection amount is formed from the first area G1 toward the second area G2, and the ink ejection amount per predetermined area of the paper S decreases.

Next, a problem that occurs when the ejection of ink from the head 21 onto the paper S is interrupted will be described.
FIG. 8 is an explanatory diagram showing an example of the state of the paper S when ink ejection is interrupted.
When ink is ejected from the head 21 toward the paper S supported by the medium support section 30, the ejected ink adheres to the surface of the paper S, and the ink adhered to the paper S permeates the inside of the paper S. . The ink penetrating into the paper S swells the wood fibers, which are the main component of the paper S, and then, as shown in FIG. bulges from the support position P of the medium support portion 30 toward the head 21 side. So-called cockling occurs. The bulging of the paper S occurs uniformly along the X-axis direction, which is the width direction of the paper S. As shown in FIG.
In addition, the degree of expansion of the paper S due to swelling changes with the lapse of time. For example, for several minutes after the ink is discharged, the swelling of the paper S becomes maximum due to the absorption of the ink. On the other hand, 10-odd minutes after the ejection of the ink, the swelling of the paper S subsides due to the evaporation of the ink.
Therefore, for example, when ink ejection is interrupted at the time of replacement of the ink cartridge 27, if the replacement work of the ink cartridge 27 takes several minutes, the swelling of the paper S becomes large and it contacts the nozzle surface 21A of the head 21. . As a result, the nozzle surface 21A becomes dirty and ink ejection failure occurs, resulting in deterioration of image quality.

Therefore, in order to prevent part of the paper S from contacting the nozzle surface 21A due to swelling, the head 21 is moved in the X-axis direction to a position where the paper S and the nozzle surface 21A do not face each other when ink ejection is interrupted. can be considered. However, even if the head 21 is retracted, it takes more than ten minutes for the swelling of the paper S to subside. You can't, and your productivity will drop.
In addition, considering the size reduction of the printer 1, the dimension in the X-axis direction is shortened. In some cases, it may not be possible to move.
In this case, it is conceivable to retract the bulging portion of the paper S with respect to the head 21 . However, in this case as well, it takes more than ten minutes for the bulge of the paper S to subside, so the paper S cannot be returned to its original position immediately after the ink cartridge 27 is replaced, resulting in a decrease in productivity. .
Therefore, in this embodiment, when the ink ejection is interrupted, the bulging portion of the sheet S is positioned in the correction area Q on the transport path V, and the posture of the sheet S is corrected.
As a result, the posture of the sheet S is corrected, and the bulging portion of the sheet S is made flatter than before the correction. As a result, even if the paper S is returned to its original position immediately after the ink cartridge 27 is replaced, the paper S does not come into contact with the nozzle surface 21A, thereby preventing ink ejection failure. Moreover, it can contribute to improvement in productivity.

Further, the portion of the sheet S that swells tends to be different depending on the print mode.
Therefore, in the present embodiment, the evacuation target portion K to be evacuated to the correction area Q is defined for each print mode, the evacuation target portion K is positioned in the correction area Q, and the posture of the sheet S is corrected. The retraction target portion K is a portion of the sheet S that swells. As a result, the posture of the paper S can be efficiently corrected according to the print mode. In the present embodiment, retracting the portion to be retracted K to the correction region Q means positioning the portion to be retracted K in the correction region Q. FIG.

The reason why the swollen portion of the paper S differs depending on the print mode is that even if the paper S is made of the same material, the expansion deformation due to the pressing of the fibers will differ due to, for example, the difference in the amount of ink ejected. it is conceivable that. For example, as shown in FIGS. 6 and 7, in the first mode, the ink discharge amount gradually decreases from the first area F1 toward the fourth area F4 and the upstream side of the fourth area F4. In the mode, the difference in ink ejection amount changes greatly from the first area G1 toward the second area G2 and the upstream side of the second area G2. In this way, it is considered that the position at which cockling occurs varies depending on the change in the amount of ink ejected on the paper S. FIG.

The retraction target portion K of the sheet S in the print mode will be specifically described below.
In this embodiment, the first mode and the second mode are described as examples of print modes.
First, the first mode is a print mode in which the amount of ink ejected per predetermined area is greater than that in the second mode. In the first mode, as shown in FIG. 6, the degree of swelling due to the swelling of the sheet S in the second area F2 is greater than in the first area F1, the third area F3, and the fourth area F4, which are the other areas. In the case of the first mode, while the ink ejection amount gradually decreases from the first area F1 toward the fourth area F4, the second area adjacent to the first area F1 where all the raster lines are formed. A large bulge occurs in the region F2. The second region F2 has the narrowest region in which raster lines are not formed as compared with the third region F3 and the fourth region F4, as shown in FIG. . For this reason, in the second region F2, the degree of expansion and deformation is higher than in the third region F3 and the fourth region F4 due to the pressing of the swollen fibers against the region where the raster lines are not formed, so the swelling does not occur. expected to grow. In the present embodiment, the upstream side of the first area F1, the second area F2, the third area F3, and the fourth area F4 are defined as the first evacuation target portion K1. That is, the first retraction target portion K1 in the first mode is the portion positioned within the scanning region E when ink ejection is interrupted.

On the other hand, in the second mode, as shown in FIG. 7, the degree of bulging on the upstream side in the transport direction adjacent to the second area G2 of the sheet S is higher than that in the first area G1 and the second area G2, which are other areas. big. In the case of the second mode, a large bulge occurs in a portion of the paper S where the difference in the amount of ink ejected is large. More specifically, the portion of the sheet S on the upstream side in the transport direction Y adjacent to the second region G2, in other words, the portion where the raster lines are not formed, is drawn toward the swollen side of the second region G2. , it is considered that the bulge is larger than that of other regions. Therefore, the upstream side of the second region G2 in the transport direction Y and the portion adjacent to the upstream side of the second region G2 in the transport direction Y, that is, the upstream side of the second region G2 in the transport direction Y and the transport of the second region G2 A portion continuing to the upstream side in the direction Y is defined as a second evacuation target portion K2. That is, the second retraction target portion K2 in the second mode includes a portion positioned within the scanning region E and a portion positioned upstream from the scanning region E when ink ejection is interrupted.

Next, the correction area Q will be explained. FIG. 9 is a schematic diagram for explaining the correction area Q. As shown in FIG.
The correction area Q is an area in which the retraction target portion K of the sheet S is retracted. The correction area Q is arranged in a different area from the scanning area E scanned by the head 21 in the conveying path V of the paper S. As shown in FIG. The correction area Q is an area for correcting the posture of the sheet S. FIG. That is, the correction region Q is a region for retracting the retraction target portion K of the paper S and correcting the attitude of the retraction target portion K of the paper S when ink ejection by the head 21 is interrupted.

In this embodiment, the correction area Q is arranged downstream of the scanning area E in the transport path V. As shown in FIG. The correction area Q of this embodiment includes a first correction area Q1 and a second correction area Q2, and the first correction area Q1 and the second correction area Q2 are arranged downstream of the scanning area E. As shown in FIG.
As a result, the first retraction target portion K1 and the second retraction target portion K2 of the paper S are retracted to the downstream side of the scanning area E. Therefore, when the paper S is retracted, the first retraction target portion K1 and the second retraction target portion K2 contact the head 21 and stain the nozzle surface 21A. Further, when the sheet S is retracted downstream from the scanning area E, part of the sheet S is discharged from the discharge port 16 and exposed to the outside of the housing 12 . Therefore, the image portion printed on the paper S is exposed to the outside air, thereby further promoting drying.

The first correction area Q1 is a speed increasing area between the first roller pair 41 and the second roller pair 42 on the transport path V. As shown in FIG. As described above, in the transport section 40, the driving rollers 45 of the first roller pair 41, the second roller pair 42, and the third roller pair 43 are accelerated with respect to the driving rollers 45 of the roller pair 44 on the upstream side. state. Therefore, the area between the first roller pair 41 and the second roller pair 42 is an area where the speed is increased.
Further, the second correction area Q2 is a concave portion 100 provided downstream of the scanning area E. As shown in FIG. The concave portion 100 of this embodiment is provided in the medium support portion 30 .

Then, when ink ejection by the head 21 is interrupted, the control unit 60 corrects at least one of the first retraction target portion K1 and the second retraction target portion K2 as the retraction target portion K according to the print mode. It is positioned in either the first correction region Q1 or the second correction region Q2.

In this embodiment, the correction area Q differs between the first mode and the second mode, and the correction area Q in the first mode is the first correction area Q1. That is, the correction area Q in the first mode is the speed increasing area between the first roller pair 41 and the second roller pair 42 . Then, when the print mode is the first mode, the control section 60 positions (retracts) the first retraction target portion K1 to the first correction area Q1. As a result, the first retraction target portion K1 is held while being accelerated by the first roller pair 41 and the second roller pair 42 . That is, the first retraction target portion K1 is pulled toward the downstream side of the transport path V, and the sheet S is held in a flattened state. At this time, the swelling portion in the first retraction target portion K1 is corrected by the pulling force. Furthermore, regarding the positional relationship between the first roller pair 41 and the second roller pair 42, the sandwiching position P1 of the paper S by the first roller pair 41 on the upstream side is greater than that of the paper S by the second roller pair 42 on the downstream side. It is positioned in the −Z direction, which is lower in the vertical direction Z than the sandwiching position P2. Further, the support position P of the medium support unit 30 is positioned in the −Z direction, which is lower in the vertical direction Z than the sandwiching position P2 of the sheet S between the second roller pair 42 . As a result, the sheet S is pressed in the -Z direction, and the first retraction target portion K1 of the sheet S is corrected.

Further, the correction area Q in the second mode is the second correction area Q2. That is, the correction area Q in the second mode is the concave portion 100 . Then, when the print mode is the second mode, the control section 60 positions the second retraction target portion K2 in the second correction area Q2. As a result, the second retraction target portion K2 is retracted to the recess 100, which is the second correction area Q2. In the second retraction target portion K2 retracted to the second correction area Q2, the bulging portion of the second retraction target portion K2 is caused by the recess 100 to act toward the bottom of the recess 100 in the direction opposite to the direction in which the recess 100 expands. It is held in a state that imitates the As a result, the swelling in the second retraction target portion K2 is eliminated, and the posture of the second retraction target portion K2 of the sheet S is corrected. The second correction area Q2 is particularly effective in correcting a portion in which the amount of change in the bulging portion becomes large after being retracted to the second correction area. Between the first to-be-restored portion K1 and the second to-be-restored portion K2 of the present embodiment, the second to-be-restored portion K2 tends to undergo a larger amount of change in the swelling portion after the elapse of a predetermined period of time.

In addition, in the present embodiment, the second correction area Q2 is arranged on the upstream side of the transport path V from the first correction area Q1.
This makes it possible to reduce the difference between the movement distance of the first evacuation target portion K1 during evacuation in the first mode and the movement distance of the second evacuation target portion K2 during evacuation in the second mode. That is, the first evacuation target portion K1 is a portion located within the scanning area E, but the second evacuation target portion K2 is a portion located within the scanning area E and a portion located upstream of the scanning area E. Therefore, when the moving distance for retracting the first retraction target portion K1 and the moving distance for retracting the second retraction target portion K2 are compared with the common correction area Q as a reference point, the second The movement distance for retracting the retraction target portion K2 is longer. Therefore, for example, if the second correction area Q2 is arranged downstream of the first correction area Q1 in the conveying path V, the movement distance for retracting the second retraction target portion K2 becomes even longer, and the printer The structure of 1 is also enlarged. Further, if the movement distance differs depending on the print mode, the transport control becomes complicated, and there is a possibility that a transport error may occur. For this reason, in the present embodiment, considering the balance between the movement distance of the retraction operation in the first mode and the movement distance of the retraction operation in the second mode, the movement distance for each print mode is shortened. A difference in moving distance can be reduced. Therefore, it is possible to reduce the size of the printer 1 and simplify the transport control.

Next, a method of controlling the printer 1 will be described. Specifically, a method of controlling the printer 1 when ink ejection by the head 21 is interrupted will be described.
10 and 11 are operation diagrams for explaining the control method of the printer 1 in the first mode. 12 and 13 are operation diagrams for explaining the control method of the printer 1 in the second mode. 10 to 13, for ease of explanation, a side view of the printer 1 viewed from the -X direction and a plan view of the paper S viewed from the +Z direction are shown in correspondence.

First, a method of controlling the printer 1 in the first mode will be described.
Based on the print data received from the host device, the control unit 60 recognizes that the print mode is the first mode, and drives the carriage 20, head 21, transport unit 40, and the like. An image is thus printed on the sheet S (see FIG. 6).

The control unit 60 determines whether or not the amount of ink remaining in the ink cartridge 27 has reached a predetermined value based on the remaining amount of ink calculated via the storage element of the ink cartridge 27 . When it is determined that the remaining amount of ink in the ink cartridge 27 has reached a predetermined value, a message is displayed on the operation panel 15 suggesting that the ink cartridge 27 should be replaced. Then, the control unit 60 stops driving the carriage 20, the head 21, the transport unit 40, and the like. As a result, ink ejection by the head 21 is interrupted. That is, print processing is interrupted.
At this time, in the example of FIG. 10, at the position of the sheet S corresponding to the scanning area E, there are a part of the first area F1 of the image formed on the sheet S, a second area F2, and a third area F3. , and the fourth region F4 are positioned.

The user replaces the ink cartridge 27 with the maintenance cover 14 opened. Here, during the replacement work of the ink cartridge 27, there is a risk that a part of the paper S will swell due to the reception of ink, bulge in a convex shape toward the head 21 side, and come into contact with the nozzle surface 21A (see FIG. 8). .
In the first mode, the portion of the sheet S corresponding to the scanning area E bulges. Among them, the bulge is particularly noticeable in the second region F2.

Therefore, when the controller 60 determines that the ink ejection by the head 21 has been interrupted, it recognizes the portion of the sheet S corresponding to the scanning area E as the first retraction target portion K1. Then, the transport unit 40 is driven to position the first retraction target portion K1 of the sheet S in the first correction area Q1 as shown in FIG. The control unit 60 stops driving the transport unit 40 when the first retraction target portion K1 of the sheet S is positioned in the first correction area Q1.
As a result, contact with the nozzle surface 21A of the swelling portion generated in the first retraction target portion K1 can be prevented.

The first correction area Q1 is an area between the first roller pair 41 and the second roller pair 42 and is a speed increasing area. The first retraction target portion K1 of the sheet S retracted to the first correction area Q1 is held between the first roller pair 41 and the second roller pair . That is, the first retraction target portion K1 is pulled toward the downstream side of the transport path V, and the sheet S is held in a flattened state. As a result, the posture of the first retraction target portion K1 is corrected.

The user replaces the ink cartridge 27 and closes the maintenance cover 14 . When the control unit 60 electrically detects the attachment of the ink cartridge 27 and the cover sensor 57 detects that the maintenance cover 14 is closed, it recognizes that the replacement of the ink cartridge 27 is completed.
Then, the control section 60 drives the transport section 40 to move the first retraction target portion K1 of the sheet S retracted to the first correction area Q1 to the scanning area E. As shown in FIG. As a result, the paper S returns to the position where the ink ejection was interrupted.
Since the first retraction target portion K1 that has returned to its original position has been flattened in the first correction region Q1, the first retraction target portion K1 does not come into contact with the nozzle surface 21A.

Next, the control unit 60 drives the carriage 20, the head 21, the conveying unit 40, and the like to resume ink ejection.

Next, a method of controlling the printer 1 in the second mode will be described.
Based on the print data received from the host device, the control unit 60 recognizes that the print mode is the second mode, and drives the carriage 20, the head 21, the transport unit 40, and the like. An image is thus printed on the sheet S (see FIG. 7).

The control unit 60 determines whether or not the amount of ink remaining in the ink cartridge 27 has reached a predetermined value based on the remaining amount of ink calculated via the storage element of the ink cartridge 27 . When it is determined that the remaining amount of ink in the ink cartridge 27 has reached a predetermined value, a message is displayed on the operation panel 15 suggesting that the ink cartridge 27 should be replaced. Then, the control unit 60 stops driving the carriage 20, the head 21, the transport unit 40, and the like. As a result, ink ejection by the head 21 is interrupted. That is, print processing is interrupted.
At this time, in the example of FIG. 12, the second area G2 of the image formed on the sheet S is positioned at the position of the sheet S corresponding to the scanning area E. As shown in FIG.

The user replaces the ink cartridge 27 with the maintenance cover 14 opened. Here, during the replacement work of the ink cartridge 27, there is a risk that a part of the paper S will swell due to the reception of ink, bulge in a convex shape toward the head 21 side, and come into contact with the nozzle surface 21A (see FIG. 8). .
In the second mode, swelling occurs in a continuous area including the upstream portion of the portion of the sheet S corresponding to the scanning area E and the upstream side of the scanning area E. FIG.

Therefore, when the control unit 60 determines that the ink ejection by the head 21 has been interrupted, the continuous area including the upstream side portion of the paper S corresponding to the scanning area E and the upstream side from the scanning area E is selected as the second evacuation target. It recognizes that it is part K2. Then, the transport unit 40 is driven to position (retreat) the second retraction target portion K2 of the sheet S to the second correction area Q2 as shown in FIG. The control unit 60 stops driving the transport unit 40 when the second retraction target portion K2 of the sheet S is positioned in the second correction area Q2.
As a result, contact with the nozzle surface 21A of the swelling portion generated in the second retraction target portion K2 can be prevented.

The second correction area Q2 is a concave portion 100 formed on the downstream side of the scanning area E of the medium support section 30. As shown in FIG. In the second retraction target portion K2 of the sheet S retracted to the second correction area Q2, the bulging portion of the second retraction target portion K2 is caused by the recess 100 to act toward the bottom of the recess 100 in the direction opposite to the swelling direction. , the second retraction target portion K<b>2 is held so as to follow the concave portion 100 . As a result, the posture of the second retraction target portion K2 of the sheet S is corrected.

The user replaces the ink cartridge 27 and closes the maintenance cover 14 . When the control unit 60 electrically detects the attachment of the ink cartridge 27 and the cover sensor 57 detects that the maintenance cover 14 is closed, it recognizes that the replacement of the ink cartridge 27 is completed.
Then, the control unit 60 drives the transport unit 40 to move the second retraction target portion K2 of the sheet S retracted to the second correction area Q2 to the scanning area E. As a result, the paper S returns to the position where the ink ejection was interrupted.
Since the posture of the second retraction target portion K2 that has returned to its original position has been corrected in the second correction region Q2, the second retraction target portion K2 and the nozzle surface 21A do not come into contact with each other.

Next, the control unit 60 drives the carriage 20, the head 21, the conveying unit 40, and the like to resume ink ejection.

As described above, according to this embodiment, the following effects can be obtained.

When the ejection of ink is interrupted, in the first mode, the portion located within the scanning region E is retracted to the first correction region Q1 as the first retraction target portion K1, and in the second mode, it is located within the scanning region E. The upstream portion and the portion upstream of the scanning region E are retracted to the second correction region Q2 as the second retraction target portion K2. As a result, it is possible to prevent the head from rubbing against the paper S when ink ejection is interrupted. Further, while ink discharge is suspended, the posture of the first retraction target portion K1 is corrected in the first correction region Q1, and the posture of the second retraction target portion K2 is corrected in the second correction region Q2. As a result, when the first retraction target portion K1 and the second retraction target portion K2 are returned to their original positions when ink ejection is restarted, the paper S does not come into contact with the nozzle surface 21A, so ink ejection can be resumed immediately. . That is, productivity can be improved.
Furthermore, since there is no need to provide an adsorption mechanism or the like for adsorbing the paper S to the medium support section 30 in order to suppress swelling of the paper S, the size and cost of the printer 1 can be reduced.

It should be noted that the present invention is not limited to the above-described embodiment, and various modifications and improvements can be made to the above-described embodiment. Modifications are described below.

(Modification 1) In the above-described embodiment, the correction area Q is arranged on the downstream side of the scanning area E in the transport path V for transporting the sheet S, but the present invention is not limited to this. The correction area Q may be arranged on the upstream side of the scanning area E in the transport path V along which the paper S is transported.
FIG. 14 is a partial schematic diagram showing the configuration of a printer 1A according to this modification.
As shown in FIG. 14 , a notch portion 101 is formed by cutting off a part of the medium support portion 30 at the +Z direction end portion of the medium support portion 30 upstream in the transport direction. A concave space is formed between the notch 101 and the driving roller 45 of the roller pair 44 when viewed from the -X direction. The space is an area provided on the upstream side of the scanning area E in the transport path V for transporting the paper S, and the area may be the third correction area Q3(Q). Further, the conveying path V following the path forming member 19 may be the fourth correction area Q4(Q).

Even in this way, since the evacuation target portion K of the sheet S that has been evacuated to the third and fourth correction areas Q3 and Q4 is retained following the form of the third and fourth correction areas Q3 and Q4, it is evacuated. The bulging portion of the target portion K is corrected. Also, the retraction target portion K of the sheet S is retracted upstream of the scanning area E. As shown in FIG. As a result, since the paper S is retracted while being accommodated inside the printer 1A, problems such as adhesion of foreign matter to the paper S and damage to the paper S can be prevented.

(Modification 2) In the above embodiment, in the first mode, the first retraction target portion K1 is retracted to the first correction region Q1, and in the second mode, the second retraction target portion K2 is retracted to the second correction region Q2. but not limited to. Either the first mode or the second mode may be retracted to the second correction area Q2. That is, the correction area Q may be only the concave portion 100 (second correction area Q2).
Even in this way, the first portion to be evacuated K1 or the second portion to be evacuated K2 is evacuated to the recessed portion 100 and held in a state following the recessed portion 100 . Thereby, the posture of the sheet S can be corrected.

(Modification 3) In the above embodiment, in the first mode, the first retraction target portion K1 is retracted to the first correction region Q1, and in the second mode, the second retraction target portion K2 is retracted to the second correction region Q2. but not limited to. It may be retracted to the first correction area Q1 in either the first mode or the second mode. That is, the correction area Q may be only the acceleration area (first correction area Q1).
Even in this way, the first retraction target portion K1 or the second retraction target portion K2 is retracted to the first correction region Q1 and held between the first roller pair 41 and the second roller pair 42 . Thereby, the posture of the sheet S can be corrected.

(Modification 4) In the above embodiment, in the first mode, the first retraction target portion K1 is retracted to the first correction region Q1, and in the second mode, the second retraction target portion K2 is retracted to the second correction region Q2. but not limited to. In the first mode, the first retraction target portion K1 may be retracted to the second correction area Q2, and in the second mode, the second retraction target portion K2 may be retracted to the first correction area Q1. In this way, the posture of the sheet S can also be corrected.

(Modification 5) In the above-described embodiment, the ink discharge is interrupted by exchanging the ink cartridge 27, but the present invention is not limited to this. For example, when the user stops the printing operation by operating the operation panel 15 when he or she notices an error in the print settings or print data, the ink ejection may be interrupted. can be replenished, ink ejection may be interrupted when ink is replenished, or ink ejection may be interrupted when a paper discharge stacker for slip sheets is mounted near the paper discharge port 16. It may be the case. Even if it does in this way, the effect similar to the above can be acquired.

(Modification 6) In the above-described embodiment, the distance dimension corresponding to the transport path V in the scanning area E and the transport path V between the first roller pair 41 and the second roller pair 42 in the first correction area Q1. Although the distance dimension was substantially the same as the distance dimension, if the distance dimension corresponding to the conveying path V in the scanning region E is larger than the distance dimension between the first roller pair 41 and the second roller pair 42 in the first correction region Q1 If the distance dimension corresponding to the transport path V between them is shorter, the first evacuation target portion K1 in the first mode is replaced with the second region F2 having the largest bulge in the scanning region E as the first evacuation target portion K1. , and is retracted to the first correction area Q1. By doing so, it is possible to efficiently correct the paper S and prevent the paper S from coming into contact with the nozzle surface 21A.

(Modification 7) In the above embodiment, the sheet S of the same type has been described. Alternatively, a control method may be used in which whether or not to retract each sheet S is selected. For example, in the case of plain paper, the retraction target portion K is defined and retracted to the correction area Q. In the case of glossy photo paper, the retraction may not be performed because swelling due to swelling does not occur.
In addition, the evacuation target portion K may be appropriately defined and evacuated to the correction area Q according to various print modes. Even if it does in this way, the effect similar to the above can be acquired.

The contents derived from the embodiment are described below.

An inkjet printer includes a transport unit for transporting a medium, an inkjet head capable of ejecting ink onto the transported medium, and a control unit for controlling the transport unit. When the ejection is interrupted, the retraction target portion of the medium is positioned in a correction area for correcting the attitude of the medium, which is an area different from the scanning area scanned by the inkjet head in the transportation path of the medium, and the ejection is interrupted. When the ink ejection is in the first mode, the retraction target portion is a portion located within the scanning area when the ink ejection is interrupted, and the interrupted ink ejection is in the first mode. In the second mode, in which the amount of ink ejected per predetermined area is smaller, the retraction target portion includes a portion located within the scanning area when the ink ejection is interrupted, and a portion upstream of the scanning area. and a portion located.

When ink ejection by the inkjet head is interrupted, if the portion of the medium onto which the ink is ejected stays in the scanning area of the inkjet head, the portion of the medium on which the ink is ejected and the periphery of that portion swell due to the water content of the ink. and inflate. When the bulging portion of the medium comes into contact with the inkjet head, the inkjet head surface becomes dirty, ink ejection failure occurs, and image quality deteriorates.
Therefore, according to the above configuration, the portion of the medium that may swell when ink ejection by the inkjet head is interrupted is positioned as the retraction target portion in the correction area different from the scanning area. As a result, contact between the medium and the inkjet head due to swelling can be prevented, and ejection failures of the inkjet head can be reduced.
Further, in the above configuration, the retraction target portion of the medium to be retracted to the correction area differs depending on the ink ejection mode, that is, the amount of ink ejected. This is because even if the medium is of the same type, the swelling portion of the medium differs depending on the ink ejection amount.
Therefore, when there are a first mode of ink ejection and a second mode in which the amount of ink ejected per predetermined area is smaller than that of the first mode, in the case of the first mode, the portion located within the scanning area of the medium is It is retracted to the correction area as the retraction target portion. On the other hand, in the case of the second mode, a portion including a portion located within the scanning region and a portion located upstream from the scanning region is retracted to the correction region as a retraction target portion.
Here, the correction area is an area in which the posture of the medium is corrected, and the posture of the medium is corrected in the correction region in each of the portion to be evacuated in the first mode and the portion to be evacuated in the second mode. That is, the bulge in each evacuation target portion is eliminated, and the medium is flattened.
Therefore, when ink ejection is resumed after ink ejection is interrupted, when the retraction target portion is returned to the scanning area, the retraction target portion of the medium has been corrected in posture, so that the retraction target portion and the inkjet head come into contact with each other. do not do. As a result, the ink jet head is not smeared, and ejection defects of the ink jet head can be reduced.
In summary, according to the above configuration, the portion to be retracted to the correction area is retracted differently according to the ink ejection mode, and the posture of the medium is corrected in the retracted correction area. This prevents the medium from rubbing against the inkjet head when ink ejection is interrupted, and prevents the medium from rubbing against the inkjet head when ink ejection is resumed. Therefore, image quality can be improved.

In the inkjet printer described above, it is preferable that the correction area is located downstream of the scanning area in the transport path along which the medium is transported.

According to this configuration, since the retraction target portion of the medium is retracted downstream of the scanning area, the retraction target portion does not contact the inkjet head and stain the inkjet head when the medium is retracted. In addition, when the medium is retracted to the downstream side of the scanning area, part of the medium may be exposed to the outside of the inkjet printer.

It is preferable that the correction area of the inkjet printer is a concave portion provided on the downstream side and recessed in the direction of gravity.

According to this configuration, the portion of the medium to be retracted is retracted into the concave portion. The portion of the medium to be evacuated that has been evacuated to the recess is held so as to follow the recess. At this time, the bulging portion in the retraction target portion is corrected by the concave portion in a direction opposite to the bulging direction.

In the above ink jet printer, the correction area differs between the first mode and the second mode, and the correction area in the second mode is recessed in the direction of gravity. A recess is preferred.

According to this configuration, the part to be saved in the first mode and the part to be saved in the second mode are saved to different areas. Then, particularly in the case of the second mode, the portion to be retracted is retracted to the concave portion, and the posture of the medium in the portion to be retracted is corrected.

In the inkjet printer, as the transport unit, a first paper discharge roller provided downstream of the scanning area in the transport path, and a first paper discharge roller provided downstream of the first paper discharge roller in the transport path, and a second paper discharge roller driven by the same drive source as the first paper discharge roller, wherein the transport amount of the medium per predetermined drive amount of the second paper discharge roller is greater than that of the first paper discharge roller. Largely, the correction area is preferably a speed increasing area between the first paper discharge roller and the second paper discharge roller in the transport path.

According to this configuration, the portion of the medium to be retracted is retracted between the first paper discharge roller and the second paper discharge roller. The portion of the medium to be evacuated that has been evacuated between the first and second discharge rollers is held in a state of being pulled downstream of the transport path by the acceleration processing by the second discharge roller. . That is, the medium is held flat. At this time, the bulging portion in the retraction target portion is corrected by the pulling force.
Also, the medium is held in a flattened state in the acceleration region. That is, the portion of the image area formed on the medium is not deformed. Thereby, image quality can be improved.

In the inkjet printer, the transport unit includes a first discharge roller provided downstream of the scanning area in the transport path, and a first discharge roller provided downstream of the first discharge roller in the transport path. and a second paper discharge roller driven by the same drive source as the first paper discharge roller, wherein the transport amount of the medium per predetermined drive amount of the second paper discharge roller is greater than that of the first paper discharge roller. In general, a region between the first discharge roller and the second discharge roller in the transport path is a speed increasing region, and the speed increases in the first mode and the second mode. Correction regions are different from each other, and the correction region in the first mode is preferably the acceleration region.

According to this configuration, the part to be saved in the first mode and the part to be saved in the second mode are saved to different areas. In the case of the first mode, the portion to be retracted is retracted to the acceleration area, and the orientation of the medium in the portion to be retracted is corrected.

In the inkjet printer, the control unit positions the retraction target portion in the first mode in a first correction area as the correction area when in the first mode, and positions the retraction target portion in the first mode in the second mode. It is preferable that the retraction target part in the second mode is positioned in a second correction area upstream of the first correction area.

According to this configuration, it is possible to shorten the moving distance in each mode by considering the balance between the moving distance of the retracting operation in the first mode and the moving distance of the retracting operation in the second mode. That is, according to the above configuration, it is possible to reduce the difference between the movement distance during retraction in the first mode and the movement distance during retraction in the second mode. When the transport amount is large, transport errors are likely to occur. If there is a difference between the transport errors occurring in the first mode and the transport errors occurring in the second mode, transport control at the time of restarting ink ejection becomes complicated. Therefore, by minimizing the difference between the transport amount in the first mode and the transport amount in the second mode, the transport path can be shortened and the transport control can be simplified.

In the inkjet printer described above, it is preferable that the correction area is located upstream of the scanning area in a transport path along which the medium is transported.

According to this configuration, the retraction target portion of the medium is retracted upstream from the scanning area. Here, when the part of the medium to be retracted is retracted to the downstream side of the scanning area, when part of the medium is exposed outside the inkjet printer, problems such as adhesion of foreign matter to the medium and damage to the medium may occur. Concerned. According to the above configuration, since the medium can be evacuated while being accommodated inside the inkjet printer, it is possible to prevent problems such as adhesion of foreign matter to the medium and damage to the medium.

A control method for an inkjet printer is a control method for an inkjet printer including a transport unit that transports a medium, an inkjet head capable of ejecting ink onto the transported medium, and a control unit that controls the transport unit. Then, when the ejection of ink by the inkjet head is interrupted, the retraction target portion of the medium is located in a correction area for correcting the attitude of the medium, which is a different area from the scanning area scanned by the inkjet head on the conveying path. and when the interrupted ink ejection is in the first mode, the retraction target portion is a portion located within the scanning area when the ink ejection is interrupted, and the interrupted ink ejection is: In the second mode, in which the amount of ink ejected per predetermined area is smaller than that in the first mode, the retraction target portion includes a portion located within the scanning area when the ink ejection is interrupted, and a portion located within the scanning area when the ink ejection is interrupted. and a portion positioned further upstream.

When ink ejection by the inkjet head is interrupted, if the portion of the medium onto which the ink is ejected stays in the scanning area of the inkjet head, the portion of the medium on which the ink is ejected and the periphery of that portion swell due to the water content of the ink. and inflate. When the bulging portion of the medium comes into contact with the inkjet head, the inkjet head surface becomes dirty, ink ejection failure occurs, and image quality deteriorates.
Therefore, according to the above configuration, the portion of the medium that may swell when ink ejection by the inkjet head is interrupted is positioned as the retraction target portion in the correction area different from the scanning area. As a result, contact between the medium and the inkjet head due to swelling can be prevented, and ejection failures of the inkjet head can be reduced.
Further, in the above configuration, the retraction target portion of the medium to be retracted to the correction area differs depending on the ink ejection mode, that is, the amount of ink ejected. This is because even if the medium is of the same type, the swelling portion of the medium differs depending on the ink ejection amount.
Therefore, when there are a first mode of ink ejection and a second mode in which the amount of ink ejected per predetermined area is smaller than that of the first mode, in the case of the first mode, the portion located within the scanning area of the medium is It is retracted to the correction area as the retraction target portion. On the other hand, in the case of the second mode, a portion including a portion located within the scanning region and a portion located upstream from the scanning region is retracted to the correction region as a retraction target portion.
Here, the correction area is an area in which the posture of the medium is corrected, and the posture of the medium is corrected in the correction region in each of the portion to be evacuated in the first mode and the portion to be evacuated in the second mode. That is, the bulge in each evacuation target portion is eliminated, and the medium is flattened.
Therefore, when ink ejection is resumed after ink ejection is interrupted, when the retraction target portion is returned to the scanning area, the retraction target portion of the medium has been corrected in posture, so that the retraction target portion and the inkjet head come into contact with each other. do not do. As a result, the ink jet head is not smeared, and ejection defects of the ink jet head can be reduced.
In summary, according to the above configuration, the portion to be retracted to the correction area is retracted differently according to the ink ejection mode, and the posture of the medium is corrected in the retracted correction area. This prevents the medium from rubbing against the inkjet head when ink ejection is interrupted, and prevents the medium from rubbing against the inkjet head when ink ejection is resumed. Therefore, image quality can be improved.

DESCRIPTION OF SYMBOLS 1... Printer (inkjet printer), 1A... Printer (inkjet printer), 2... Main body part, 3... Discharged paper receiving part, 4... Paper collection part, 8... Support, 9... Base, 12... Housing, 13... Paper feed cover 14 Maintenance cover 15 Operation panel 16 Paper ejection port 17 Supply port 18 Frame 19 Path forming member 20 Carriage 20A Main body 20B Cover 21 Head (Inkjet head) 21A Nozzle surface 22 Movement mechanism 23 Carriage motor 24 Pulley 25 Timing belt 26 First encoder 27 Ink cartridge 30 Medium support 31 Press roller , 32... Guide shaft 33... Rail part 35... Feeding part 36... Feeding shaft 37... Feeding motor 39... Carrying motor 40... Carrying part 41... First roller pair 42... Second Roller pair 43 Third roller pair 44 Roller pair 45 Drive roller 46 Driven roller 47 Support member 48 Support member 50 Medium cutting unit 51 Drive blade 52 Driven blade , 57... Cover sensor, 58... Second encoder, 59... Medium detector, 60... Control unit, 61... CPU, 62... First counter, 63... Second counter, 65... Memory, 90... Paper discharge unit, 100 Recess 101 Notch S Paper (medium) K1 First retraction target portion K2 Second retraction target portion V Conveyance path E Scanning region Q Correction region Q1 Third 1 correction area (correction area), Q2... second correction area (correction area), Q3... third correction area (correction area), Q4... fourth correction area (correction area).

Claims (9)

a transport unit that transports the medium;
an inkjet head capable of ejecting ink onto the medium being conveyed;
A control unit that controls the transport unit,
When ink ejection by the inkjet head is interrupted, the control unit sets the retraction target portion of the medium to a different area from the scanning area scanned by the inkjet head in the medium transport path and downstream of the scanning area. provided on the side and positioned in a correction area for correcting the posture of the medium;
when the interrupted ink ejection is in the first mode, the retraction target portion is a portion located within the scanning area when the ink ejection is interrupted;
When the interrupted ink ejection is in the second mode in which the amount of ink ejected per predetermined area is smaller than that in the first mode, the retraction target portion is within the scanning area when the ink ejection is interrupted. and a portion located upstream from the scanning area. The inkjet printer of claim 1 , wherein
The inkjet printer, wherein the correction area is a concave portion provided on the downstream side and recessed in the direction of gravity. a transport unit that transports the medium;
an inkjet head capable of ejecting ink onto the medium being conveyed;
A control unit that controls the transport unit,
The control unit controls the ink jet head to stop the ejection of the medium.
The inkjet head scans the retraction target portion of the body in the medium transport path.
positioned in a correction region that is different from the scanning region and corrects the orientation of the medium;
When the interrupted ink ejection is in the first mode, the retraction target portion is
a portion located within the scanning region when ejection is interrupted;
In the interrupted ink ejection, the amount of ink ejected per predetermined area is reduced from the first mode.
In the small second mode, the retraction target portion is
including a portion located within the scanning region and a portion located upstream from the scanning region;
The correction areas are different between when the first mode and the second mode,
An ink jet printer, wherein the correction area in the second mode is a recess recessed in the direction of gravity. a transport unit that transports the medium;
an inkjet head capable of ejecting ink onto the medium being conveyed;
A control unit that controls the transport unit,
The control unit controls the ink jet head to stop the ejection of the medium.
The inkjet head scans the retraction target portion of the body in the medium transport path.
positioned in a correction region that is different from the scanning region and corrects the orientation of the medium;
When the interrupted ink ejection is in the first mode, the retraction target portion is
a portion located within the scanning region when ejection is interrupted;
In the interrupted ink ejection, the amount of ink ejected per predetermined area is reduced from the first mode.
In the small second mode, the retraction target portion is
including a portion located within the scanning region and a portion located upstream from the scanning region;
As the transport unit,
a first discharge roller provided downstream of the scanning area in the transport path;
a second paper discharge roller provided downstream of the first paper discharge roller in the transport path and driven by the same drive source as the first paper discharge roller;
The conveying amount of the medium per predetermined driving amount of the second paper discharge roller is larger than that of the first paper discharge roller,
The inkjet printer, wherein the correction area is a speed increasing area between the first paper discharge roller and the second paper discharge roller in the transport path. a transport unit that transports the medium;
an inkjet head capable of ejecting ink onto the medium being conveyed;
A control unit that controls the transport unit,
The control unit controls the ink jet head to stop the ejection of the medium.
The inkjet head scans the retraction target portion of the body in the medium transport path.
positioned in a correction region that is different from the scanning region and corrects the orientation of the medium;
When the interrupted ink ejection is in the first mode, the retraction target portion is
a portion located within the scanning region when ejection is interrupted;
In the interrupted ink ejection, the amount of ink ejected per predetermined area is reduced from the first mode.
In the small second mode, the retraction target portion is
including a portion located within the scanning region and a portion located upstream from the scanning region;
As the transport unit,
a first discharge roller provided downstream of the scanning area in the transport path;
a second paper discharge roller provided downstream of the first paper discharge roller in the transport path and driven by the same drive source as the first paper discharge roller;
The transport amount of the medium per predetermined drive amount of the second paper discharge roller is greater than that of the first paper discharge roller, and the distance between the first paper discharge roller and the second paper discharge roller in the transport path is is the acceleration area,
The correction areas are different between when the first mode and the second mode,
An inkjet printer, wherein the correction area in the first mode is the acceleration area. a transport unit that transports the medium;
an inkjet head capable of ejecting ink onto the medium being conveyed;
A control unit that controls the transport unit,
The control unit controls the ink jet head to stop the ejection of the medium.
The inkjet head scans the retraction target portion of the body in the medium transport path.
positioned in a correction region that is different from the scanning region and corrects the orientation of the medium;
When the interrupted ink ejection is in the first mode, the retraction target portion is
a portion located within the scanning region when ejection is interrupted;
In the interrupted ink ejection, the amount of ink ejected per predetermined area is reduced from the first mode.
In the small second mode, the retraction target portion is
including a portion located within the scanning region and a portion located upstream from the scanning region;
The control unit
When in the first mode, the retraction target portion in the first mode is positioned in the first correction area as the correction area;
When in the second mode, in the second correction region on the upstream side of the first correction region, the second correction region
An inkjet printer characterized by positioning the retraction target portion in a mode. In the inkjet printer according to any one of claims 3 to 6 ,
An inkjet printer, wherein the correcting area is located downstream of the scanning area in the transport path along which the medium is transported. a transport unit that transports the medium;
an inkjet head capable of ejecting ink onto the medium being conveyed;
A control unit that controls the transport unit,
When ink ejection by the inkjet head is interrupted, the control unit sets the retraction target portion of the medium to a different area from the scanning area scanned by the inkjet head in the medium transport path and upstream of the scanning area. provided on the side and positioned in a correction area for correcting the posture of the medium;
when the interrupted ink ejection is in the first mode, the retraction target portion is a portion located within the scanning area when the ink ejection is interrupted;
When the interrupted ink ejection is in the second mode in which the amount of ink ejected per predetermined area is smaller than that in the first mode, the retraction target portion is within the scanning area when the ink ejection is interrupted. and a portion located upstream from the scanning area. A control method for an inkjet printer comprising a transport unit that transports a medium, an inkjet head capable of ejecting ink onto the transported medium, and a control unit that controls the transport unit,
When ink ejection by the inkjet head is interrupted, the retraction target portion of the medium is an area different from the scanning area scanned by the inkjet head in the transport path, and is provided upstream or downstream from the scanning area, positioned in a correction area for correcting the posture of the medium;
when the interrupted ink ejection is in the first mode, the retraction target portion is a portion located within the scanning area when the ink ejection is interrupted;
When the interrupted ink ejection is in the second mode in which the amount of ink ejected per predetermined area is smaller than that in the first mode, the retraction target portion is within the scanning area when the ink ejection is interrupted. A control method for an inkjet printer, comprising: a portion located on the scanning area; and a portion located on the upstream side of the scanning area.

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