Printer

Abstract

To prevent expansion and contraction of a medium, and deviation of a cut position.SOLUTION: Printers (1 and 2) have a conveyance part (30), an ink head (40), a drying part (60) which has a heater (61) for generating heat and dries ink discharged to a medium (M), a cutting part (50) for cutting a part where an image is formed from the medium (M), and a control part (10), wherein the drying part (60) includes a blowing fan (23) for blowing heat toward the medium (M), when cutting operation by the cutting part (50) is performed, the control part (10) executes at least any control of reduction of a heat generation amount of the heaters (61 and 69), and reduction of a blowing amount of the blowing fan (23), compared to the time when the ink is dried.SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present invention relates to a printing apparatus.

Background Art

[0002] Conventionally, a printing apparatus including an ink head that discharges ink onto a medium to print an image and a cutter that cuts a predetermined area (for example, an area where an image is printed) from the medium is known. For example, Patent Document 1 discloses a technique related to a printing apparatus (processing apparatus) that collectively executes printing processing and cutting (severing) processing based on aggregated job data obtained by aggregating a plurality of job data.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a printing apparatus such as an inkjet printer, a drying device may be provided to promote drying of ink by heating a medium on which an image is printed. Therefore, by providing a drying device in a printing apparatus capable of performing printing and cutting processes as in Patent Document 1, it is conceivable to shorten the time from printing an image on a medium to drying the image. However, if the medium is heated more than necessary by the drying device, the medium may expand and contract due to heat or be damaged by heat. As a result, there is a risk that the cutting position may shift due to the expansion and contraction of the medium.

[0005] An object of the present invention is to suppress the medium from expanding and contracting and causing the cutting position to shift.

Means for Solving the Problems

[0006] The main invention for achieving the above object is a printing apparatus having a conveyance unit that conveys a medium in a conveyance direction, an ink head that discharges ink onto the medium to form an image, a heater that generates heat, a drying unit that dries the ink discharged onto the medium, a cutting unit that cuts a portion of the medium on which an image is formed, and a control unit. The drying unit includes a blower fan that blows the heat toward the medium. When the cutting operation is performed by the cutting unit after the image forming operation by the ink head, the control unit executes at least one of the controls of reducing the heat generation amount of the heater and reducing the blowing amount of the blower fan. This is a printing apparatus characterized by the above.

[0007] Other features of the present invention will be clarified by the description in this specification.

Effect of the Invention

[0008] According to the present invention, when drying and cutting an image printed on a medium with a printing apparatus, it is possible to suppress the medium from expanding and contracting and the cutting position from shifting.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

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Figure 7

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Figure 10

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Figure 13

Embodiments for Carrying Out the Invention

[0010] ===First Embodiment=== <Basic Configuration of the Printing Apparatus 1> As an example of the printing apparatus according to the first embodiment, the printing apparatus 1 that prints an image by an inkjet method will be described. FIG. 1 is a perspective view for explaining the basic configuration of the printing apparatus 1. FIG. 2 is a schematic cross-sectional view when the printing apparatus 1 is viewed from the scanning direction. FIG. 3 is a block diagram of the printing apparatus 1.

[0011] In the following description, as shown in FIG. 1, each direction is defined. That is, the moving direction of the carriage 21 of the printing apparatus 1 is defined as the "scanning direction". Also, the moving direction of the medium M is defined as the "conveying direction", the side of the supply source of the medium M is defined as "upstream (upstream side)", and the discharge side of the medium M is defined as "downstream (downstream side)". Note that the direction from the downstream side toward the upstream side may be referred to as the "pull-back direction".

[0012] The printing device 1 is a device capable of printing (forming) an image on a medium M (printing paper, printing film, etc.) and drying it, and cutting a predetermined area of the medium M. For example, the printing device 1 is a serial printer with a cutter and a drying device. The printing device 1 of the present embodiment includes a controller 10, a carriage unit 20, a conveyance unit 30, a printing unit 40, a cutting unit 50, and a drying unit 60.

[0013] The controller 10 is a control unit that controls the printing device 1. The controller 10 controls the drive units of the printing device 1 (for example, the carriage motor 22 and the conveyance motor 32 shown in FIG. 3). For example, control is performed based on a command from a computer (not shown in FIG. 1) such as a personal computer operated by the user. In addition, the controller 10 controls the cutting operation by the cutting unit 50 and the drying operation by the drying unit 60. The specific control operations of the printing device 1 by the controller 10 will be described later.

[0014] The carriage unit 20 is a unit for reciprocating the carriage 21 in the scanning direction. The carriage unit 20 includes a carriage 21 and a carriage motor 22. The carriage 21 is a member that reciprocates in the scanning direction. An ink head 41 and a cutter 51 are mounted on the carriage 21, and by reciprocating the carriage 21 in the scanning direction, the ink head 41 and the cutter 51 can be reciprocated in the scanning direction. The carriage motor 22 is a drive unit for moving the carriage 21 in the scanning direction. The controller 10 controls the movement of the carriage 21 by controlling the drive of the carriage motor 22. In addition, the carriage unit 20 has a position detection unit 23 for detecting the position of the carriage 21 in the scanning direction. The position detection unit 23 may directly detect the position of the carriage 21 in the scanning direction, or may indirectly detect the position of the carriage 21 by detecting the drive amount (rotation amount) of the carriage motor 22. The position detection unit 23 feeds back the detection result to the controller 10.

[0015] In the printing apparatus 1, a long medium M is fed out from, for example, a raw material roll and conveyed along the conveyance direction (and the retraction direction) on the rear apron 4A, the platen 4B, and the front apron 4C (see FIG. 2). The conveyance unit 30 is a unit for conveying the medium M, and includes a conveyance roller 31A provided on the platen 4B, a pinch roller 31B disposed opposite to the conveyance roller 31A, and a conveyance motor 32. The conveyance roller 31A is a rotating roller for conveying the medium M on the platen 4B. By rotating the conveyance roller 31A with the medium M sandwiched between the conveyance roller 31A and the pinch roller 31B, the medium M can be conveyed in the conveyance direction (and the retraction direction). The conveyance motor 32 is a drive unit for rotating the conveyance roller 31A. The conveyance motor 32 can rotate the conveyance roller 31A in the forward rotation direction and the reverse rotation direction, whereby the medium M can be moved in the conveyance direction and the retraction direction on the platen 4B. The controller 10 controls the conveyance of the medium M by controlling the drive of the conveyance motor 32. Further, the conveyance unit 30 has a conveyance detection unit 33 for detecting the conveyance amount of the medium M. The conveyance detection unit 33 may directly detect the conveyance amount of the medium M, or may indirectly detect the conveyance amount of the medium M by detecting the rotation amount of the conveyance roller 31A or the drive amount (rotation amount) of the conveyance motor 32. The conveyance detection unit 33 feeds back the detection result to the controller 10.

[0016] The printing unit 40 is a unit for printing an image on the medium M. The printing unit 40 includes an ink head 41 and a head driving unit 42. The ink head 41 is an inkjet printing head provided with a number of nozzles for ejecting ink to form an image. The head driving unit 42 is a driving unit for causing ink to be ejected or not ejected from each nozzle of the ink head 41. The ink head 41 is mounted on the carriage 21 and reciprocates in the scanning direction together with the carriage 21. The head driving unit 42 is, for example, a heater driving unit that controls the on / off of a heater if the ink head 41 is a bubble jet type, or a driving unit that drives a piezo element if the ink head 41 is a piezo type. The controller 10 controls the ejection of ink from the ink head 41 by controlling the head driving unit 42.

[0017] The cutting unit 50 is a unit for cutting (severing) the medium M. The cutting unit 50 includes a cutter 51 and a cutter solenoid 52. The cutter 51 is a tool provided with a cutting edge for cutting the medium M. The cutter solenoid 52 is a driving unit that drives the cutter 51 along a direction perpendicular to the medium surface. The controller 10 controls the contact / non-contact between the cutting edge of the cutter 51 and the medium M and controls the contact pressure between the cutting edge of the cutter 51 and the medium M by controlling the cutter solenoid 52.

[0018] The drying unit 60 is located downstream of the printing unit 40 and the cutting unit 50 in the conveyance direction, is disposed opposite to the front apron 4C, and is a unit for heating and drying the medium M onto which ink has been ejected by the ink head 41. The drying unit 60 includes a heater 61, a heater driving unit 62, a blower fan 63, a motor 64 for the blower fan, an air curtain fan 65, and a motor 66 for the air curtain. The heater 61 is a heat source that generates heat for heating the medium M. The heater driving unit 62 is a part that supplies power to a heating element (for example, an electric resistance not shown) provided in the heater 61 and generates heat according to the supplied power. The blower fan 63 is a blower for sending air that convects the heat generated by the heater 61. The motor 64 for the blower fan is a driving unit that generates air for the blower fan 63 by rotating an impeller or the like. The air curtain fan 65 is a blower for taking in air (outside air) from outside the drying unit 60 and sending air for forming a so-called air curtain by injecting the air toward the medium M supported on the front apron 4C. The motor 66 for the air curtain is a driving unit that generates air for the air curtain fan 65. The controller 10 performs heating of the medium M and the like by controlling the heater driving unit 62, the motor 64 for the blower fan, and the motor 66 for the air curtain, respectively. A specific control method of the drying unit 60 will be described later.

[0019] As shown in FIG. 1, the printing apparatus 1 of the present embodiment is provided on a gantry 5. The gantry 5 is a base for supporting the printing apparatus 1 away from the installation surface (floor surface). Since the printing apparatus 1 is provided on the gantry 5 and the printing apparatus 1 is separated from the installation surface, the medium M discharged from the printing apparatus 1 will drip downward as shown in FIG. 1.

[0020] <Printing operation using the printing apparatus 1> Subsequently, the printing operation using the printing apparatus 1 will be described. FIG. 4 is a flowchart of the printing operation using the printing apparatus 1. FIGS. 5A to 5D are diagrams for explaining the operations of the respective parts of the printing apparatus 1 during the printing operation.

[0021] When performing a printing operation using the printing apparatus 1, first, a conveyance step of conveying the medium M in the conveyance direction is carried out (S101). In the conveyance step, the long medium M that is fed out from the original roll and supported on the platen 4B is conveyed at a predetermined conveyance speed along the conveyance direction based on the rotation of the conveyance roller 31A (and the pinch roller 31B) (see FIG. 2). Note that the medium M is basically printed with an image or the like while being conveyed from the upstream side to the downstream side in the conveyance direction. That is, an image is printed on the medium M while repeating the conveyance step (S101) and the image forming step (S102) described later and the like.

[0022] Next, an image forming step of forming an image on the conveyed medium is carried out (S102). In the image forming step, with respect to the image conveyed in the conveyance direction, while reciprocating the carriage 21 in the scanning direction, an image forming operation is performed in which ink is ejected from the ink head 41 mounted on the carriage 21 and ink droplets land on the medium M. Hereinafter, in the platen 4B, the region where the image forming operation is performed by the ink head 41 is also referred to as the printing region PA. FIG. 5A shows a case where an image (character) “A” is formed on the medium M while moving the ink head 41 in the scanning direction in the printing region PA. Note that in the image forming step, since the cutting unit 50 is not used, it is preferable to set the cutter 51 in a standby state at a position where it does not interfere with the movement of the ink head 41 (for example, at one end in the scanning direction). In this case, the carriage 21 may be configured to be able to move the ink head 41 and the cutter 51 independently in the scanning direction. Note that the carriage 21 on which the ink head 41 is mounted and the carriage 21 on which the cutter 51 is mounted may be configured to be connectable, and by being in a connected state, it may be possible to move the ink head 41 and the cutter 51 together in the scanning direction. Also, by disconnecting the connected state, the ink head 41 or the cutter 51 may be configured to be able to move independently in the scanning direction.

[0023] Next, a drying process is performed to dry and fix the image (ink droplets) formed on the medium (S103). In the drying process, the image (A) formed on the medium is conveyed downstream in the conveyance direction from the printing area PA, and a drying operation is performed at the position where the drying unit 60 is provided. Hereinafter, in the conveyance direction, the area downstream of the printing area PA in the conveyance direction where drying is performed by the drying unit 60 is also referred to as the drying area DA. FIG. 5B shows a case where the portion of the image "A" formed on the medium M is conveyed to the drying area DA and dried by the drying unit 60.

[0024] FIG. 6 is a schematic cross-sectional view for explaining the specific functions of each part constituting the drying unit 60. The drying unit 60 includes a casing 67 and an air injection port 68 in addition to the heaters 61 to the air curtain motor 66 described above. The casing 67 has an outer casing 671 that constitutes the exterior of the drying unit 60, an inner casing 672 disposed substantially parallel to the front apron 4C inside the outer casing 671, and a partition wall 673 that isolates the space surrounded by the outer casing 671 and the inner casing 672. The air injection port 68 is a gap formed by the outer casing 671 and the partition wall 673, and is the portion that serves as the outlet (injection port) of the air injected onto the medium M as an air curtain.

[0025] The interior of the drying unit 60 is mainly divided into two regions. That is, a heating chamber HR that generates heat for heating the medium and blows air toward the drying passage DR provided between the drying unit 60 and the front apron 4C, and an air curtain chamber AR that suppresses heat from escaping to the outside from within the drying passage DR by injecting air toward the medium to form an air curtain on the upstream side of the drying unit 60 in the conveyance direction.

[0026] The drying passage DR is, in FIG. 6, an area surrounded by the front apron 4C and the inner casing 672 (and a part of the partition wall 673), and heats the medium M supported on the front apron 4C by circulating the heat flow supplied from the heating chamber HR. The heating chamber HR is, in FIG. 6, an area surrounded by the inner casing 672 and the partition wall 673, and at least a heater 61 and a blower fan 63 are provided inside the heating chamber HR. The heating chamber HR is further divided into two areas by the heating chamber partition wall 674. In FIG. 6, the heating chamber HR is divided into an intake chamber HR1 below the heating chamber partition wall 674 and an exhaust chamber HR2 above the heating chamber partition wall 674. The blower fan 63 is arranged in the intake chamber HR1, and the heater 61 is arranged in the exhaust chamber HR2. Further, in a part of the boundary between the heating chamber HR and the drying passage DR in the inner casing 672, a heat flow outlet 672e and a heat flow inlet 672i are formed. The heat flow outlet 672e and the heat flow inlet 672i are formed, for example, by dispersedly providing a plurality of through holes such as punching metal. In FIG. 6, the heat flow outlet 672e is provided at the boundary between the exhaust chamber HR2 on the upstream side in the conveyance direction and the drying passage DR, and the heat flow inlet 672i is provided at the boundary between the intake chamber HR1 on the downstream side in the conveyance direction and the drying passage DR.

[0027] The air curtain chamber AR is, in FIG. 6, an area surrounded by the outer casing 671 and the partition wall 673, and at least an air curtain fan 65 is provided inside the air curtain chamber AR.

[0028] When performing the drying operation in the drying process (S103), first, the blower fan 63 generates air flowing in the direction from the intake chamber HR1 to the exhaust chamber HR2 (the blowing direction indicated by the arrow in FIG. 6). Then, the air generated by the blower fan 63 is heated by the heater 61 provided in the exhaust chamber HR2 on the downstream side in the blowing direction, and flows out from the heat outlet 672e into the drying passage DR as hot air. The hot air that has flowed out into the drying passage DR moves along the conveyance direction in the drying passage DR and heats and dries the medium M supported on the front apron 4C. At this time, an air curtain is formed by the air jetted by the air curtain fan 65 on the upstream side in the conveyance direction, and since the hot air is suppressed from moving from the downstream side to the upstream side in the conveyance direction, the hot air moves from the heat outlet 672e to the downstream side in the conveyance direction. Then, due to the negative pressure during the operation of the blower fan 63, it is sucked from the heat inlet 672i into the intake chamber HR1, reheated in the exhaust chamber HR2, and sent to the drying passage DR. That is, in the drying section 60 of the present embodiment, the medium M is heated and dried by blowing and circulating the air heated in the heating chamber HR into the drying passage DR.

[0029] Also, during the drying operation, the above-described air curtain is formed. The air curtain fan 65 takes in air (outside air) into the air curtain chamber AR from the outside of the drying unit 60 through an intake port (not shown). The taken-in air is sent through the flow path formed by the outer casing 671 and the partition wall 673 inside the air curtain chamber AR in the direction indicated by the arrow in FIG. 6. Then, at the upstream position in the conveyance direction of the drying unit 60, it is jetted from the air jet port 68 formed at the ends of the outer casing 671 and the partition wall 673 toward the medium M supported on the front apron 4C. The flow of the jetted air becomes a wall (air curtain), suppressing the entry and exit of air between the drying passage DR and the outside thereof. That is, it is possible to suppress the hot air from escaping to the outside from the drying passage DR, and the efficiency of the drying operation can be increased. Note that a part of the air jetted toward the medium M by the air curtain fan 65 flows into the inside of the drying passage DR. However, in the drying unit 60 of the printing apparatus 1, the air curtain fan 65 does not necessarily have to be provided. That is, the air curtain does not necessarily have to be formed during the drying operation or the cutting operation.

[0030] Next, returning to FIG. 4, after the drying process, a cutting process for cutting a predetermined area (the area where the image A is printed) of the medium M is performed (S104). In the cutting process, a cutting operation is performed in which the portion of the image A formed and dried on the medium M is pulled back to the printing area PA and cut using the cutting unit 50. That is, the cutting operation is performed in the printing area PA. In FIG. 5C, in the conveyance direction, the medium M (image A) located in the drying area DA is conveyed from the downstream side to the upstream side in the conveyance direction and pulled back to the area where the image is to be cut. Then, as shown in FIG. 5D, while moving the medium M (image A) along the conveyance direction, the cutter 51 is reciprocally moved in the scanning direction to cut the area where the image A of the medium M is printed (for example, the portion along the contour of the image A in FIG. 5D). Note that in the cutting process, since the printing unit 40 is not used, it is preferable to keep the ink head 41 in a standby state at a position where it does not interfere with the movement of the cutter 51 (for example, the other end in the scanning direction).

[0031] In this cutting step (S104), when cutting a predetermined area (the area where image A is formed) of the medium M, it is necessary to identify the predetermined area (i.e., the area to be cut). As an example of a method for identifying the cutting area, for example, in the image forming step (S102), a plurality of marks (not shown) indicating the positions of the outer edges of the area (printing area) where image A is to be formed in advance are printed, and the retraction amount is calculated considering the conveyance amount and the expansion and contraction of the medium due to passing through the drying area from the positions of the marks, thereby identifying the cutting area.

[0032] In this way, by sequentially performing the steps S101 to S104 shown in FIG. 4, the printing operation can be performed.

[0033] <Regarding the misalignment in the cutting step> In the printing operation using the printing apparatus 1, after performing the drying step (S103) for drying the image formed on the medium M, the cutting step (S104) for cutting the medium M is performed. Therefore, in the cutting step, it is necessary to retract the medium M in the dried state heated by the drying unit 60 in the drying area to the printing area and then cut the area where the image is formed. Further, the medium M contracts or expands (expands and contracts) when heated. Therefore, the retraction amount is calculated considering the conveyance amount and the expansion and contraction amount due to drying.

[0034] However, during the cutting operation, since the medium M is retracted from the drying area to the printing area, the medium M is also heated while being retracted from the drying area to the printing area. That is, even after the drying step (S103) is completed, the medium M continues to be heated by the drying unit 60, causing the medium M to expand and contract. Therefore, even when the medium is retracted by the amount of retraction calculated considering the conveyance amount and the expansion and contraction amount due to drying, the cutting area (cutting position) may shift. Therefore, in order to suppress the expansion and contraction of the medium due to heat before performing the cutting operation after drying, either one or both of the heater driving unit 62 or the blower fan motor 64 are controlled.

[0035] Also, after drying, if the medium M continues to be heated by the drying unit 60 until the cutting operation is performed, the amount of expansion and contraction generated by heat is also non-uniform, making it difficult to predict in advance. This is because the cutting operation for cutting the printed image cuts only the printed area, so unlike the printing operation, the medium M does not move at a constant speed. That is, the conveyance speed of the medium M becomes slower or faster depending on the printed image or the printed area. For example, in the printing area, it is conveyed at a relatively slow speed at which the cutting operation can be performed, and in the non-printing area, it is conveyed at the normal conveyance speed. Therefore, when the cutting operation is performed, non-uniform heat is applied to the medium M, resulting in non-uniform expansion and contraction and a decrease in accuracy. Thus, in the present embodiment, when the cutting operation is performed, control is performed so that the medium M is not heated or the temperature at which it is heated is lowered in the drying area as compared with the case where the printing operation is performed.

[0036] Also, after drying, if the medium M continues to be heated by the drying unit 60 until the cutting operation is performed, not only expansion and contraction but also conveyance clogging occurs due to heat. In the cutting operation, since the feed speed of the medium M is high for the non-printed part (the part where the cutting operation is not performed), the leading end of the medium may cause conveyance clogging by riding on the wind of the fan. For this reason as well, when the cutting operation is performed, control is performed so that the air blowing by the fan becomes weaker as compared with the case of the printing operation.

[0037] Figs. 7A to 7C are diagrams for explaining the control method of each part of the drying unit 60. Fig. 7A is a diagram for explaining the control method of the calorific value (heating temperature) of the heater 61 among the drying unit 60. Fig. 7B is a diagram for explaining the control method of the air volume of the blower fan 63. Fig. 7C is a diagram for explaining the control method of the air injection amount of the air curtain fan 65.

[0038] In the printing operation described with reference to FIG. 4, in the image forming step (S102), each part of the drying unit 60 (heater 61, blower fan 63, air curtain fan 65) is OFF (see FIGS. 7A to 7C). This is because it is not necessary to heat and dry the medium M by the drying unit 60 at the stage of forming an image on the medium M. However, in the image forming step, each part of the drying unit 60 (heater 61, blower fan 63, air curtain fan 65) may be turned ON, and each part of the drying unit 60 may be controlled so that the medium M can be heated by the drying unit 60. In this case, also in the image forming step, each part of the drying unit 60 may be operated in the same manner as in the drying step described below.

[0039] Next, in the drying step (S103), each part of the drying unit 60 is operated. The controller 10 (control unit) controls each part so that the heat generation amount by the heater 61 is H1, the air volume by the blower fan 63 is F1, and the air injection amount by the air curtain fan 65 is C2. In the drying operation, in order to dry the ink ejected onto the medium M, the heat generation amount H1 of the heater 61 and the air volume F1 of the blower fan 63 are set to be high, and control is performed so that the medium M can be sufficiently heated. Further, by controlling the air curtain motor 66 so that the air injection amount C2 of the air curtain fan 65 is larger than that during the printing operation, while suppressing the escape of hot air from the inside of the drying passage DR to the outside, the air (outside air) having a low temperature for forming the air curtain is prevented from flowing excessively into the inside of the drying passage DR. Also, by controlling the air volume by the air curtain fan 65 to be increased, the floating of the paper during the backward movement can also be suppressed.

[0040] Next, in the cutting step (S104), control is performed to weaken the operation of each part of the drying unit 60. The controller 10 (control unit) controls the heating amount of the heater 61 to be H2, which is smaller than H1, as shown in FIG. 7A. That is, the heating amount (H2) of the heater 61 during the cutting operation is controlled to be decreased compared to the heating amount (H1) of the heater 61 during the drying operation (H1 > H2). By decreasing the heating amount of the heater 61, it is possible to suppress the medium M from being overheated when it is pulled back. Although the heating of the heater 61 may be stopped, since it takes a predetermined time to raise the heater 61 to the drying temperature, it is preferable to decrease the heating amount of the heater 61 rather than stopping the heating of the heater 61. Here, the cutting operation time includes not only the time when the cutting operation of the medium M is performed, but also the time when the medium M in a state where the image is dried is being pulled back.

[0041] Also, in the cutting step (S104), the controller 10 (control unit) controls the air volume of the blower fan 63 to be F2, which is smaller than F1, as shown in FIG. 7B. That is, the air volume (F2) of the blower fan 63 during the cutting operation is controlled to be decreased compared to the air volume (F1) of the blower fan 63 during the drying operation, and the blower fan motor 64 is controlled accordingly (F1 > F2). By decreasing the air volume of the blower fan 63, the total amount of heat sent to the medium M by the wind becomes smaller, so that the medium M is suppressed from being overheated. Although the blowing by the blower fan 63 may be stopped, if the blower fan 63 is stopped, the temperature of the heater 61 may become too high. For this reason, when stopping the blower fan 63, it is necessary to perform fine control such as repeating on and off so that the temperature of the heater 61 does not become too high. For this reason, it is preferable to control the air volume (F2) of the blower fan 63 so that it is decreased compared to the air volume (F1) of the blower fan 63 during the drying operation, rather than stopping the blower fan 63, so that the heater 61 does not become too high.

[0042] Also, in the cutting process (S104), the controller 10 (control unit) controls the air injection amount by the air curtain fan 65 to be C1, which is larger than C2, as shown in FIG. 7C. That is, the air curtain motor 66 is controlled so that the air injection amount (C1) of the air curtain fan 65 during the cutting operation is increased compared to the air injection amount (C2) of the air curtain fan 65 during the drying operation (C2 < C1). By increasing the air injection amount of the air curtain fan 65, outside air with a low temperature easily flows into the drying passage DR, and the temperature in the drying passage DR decreases, so that the medium is prevented from being overheated.

[0043] In FIGS. 7A to 7C, the controller 10 (control unit) weakens the heating of the medium M by controlling the heater 61, the blower fan 63 (blower fan motor 64), and the air curtain fan 65 (air curtain motor 66) respectively. However, the heating of the medium M may be weakened by controlling at least any one of the heater 61, the blower fan 63, and the air curtain fan 65 as described above. For example, during the drying operation and the cutting operation, only the heat generation amount of the heater 61 may be decreased, and the control of the blower fan 63 and the air curtain fan 65 may not be changed. Even in such a case, by decreasing the heat generation amount of the heater 61, the effect of suppressing the overheating of the medium M during the cutting operation can be obtained.

[0044] As described above, in the printing apparatus 1 of the present embodiment, by weakening the heating of the medium M during the cutting operation compared to the heating of the medium M during the drying operation, the expansion and contraction of the medium due to heating are suppressed, and it is possible to suppress the displacement of the cutting position of the medium M during the cutting operation.

[0045] Furthermore, when the air curtain fan 65 is provided in the drying unit 60, by increasing the air injection amount of the air curtain fan 65 during the cutting operation compared to the air injection amount of the air curtain fan 65 during the drying operation, the expansion and contraction of the medium due to heating can be suppressed, and it is possible to suppress the cutting position of the medium M from shifting during the cutting operation.

[0046] Also, in the cutting process (S104), the controller 10 (control unit) executes control so that both the heat generation amount H2 of the heater 61 and the air volume F2 of the blower fan 63 are greater than zero. In order to weaken the heating of the medium M during the cutting operation, it is preferable to make the heat generation amount H2 of the heater 61 as low as possible. However, if the heat generation amount H2 of the heater 61 is set to zero (i.e., the heater 61 is turned off), the time and energy consumption required to heat the heater 61 to the heat generation amount H1 in the next printing operation will increase. On the other hand, by setting the heat generation amount H2 of the heater 61 to be greater than zero and maintaining a state similar to a so-called warm-up operation, it is possible to smoothly transition to the next printing operation.

[0047] Similarly, in order to weaken the heating of the medium M during the cutting operation, it is preferable to make the air volume F2 of the blower fan 63 as low as possible. However, if the air volume F2 of the blower fan 63 is set to zero (i.e., the blower fan 63 is turned off), the residual heat of the heater 61 is likely to accumulate in the heating chamber HR of the drying unit 60, and there is a risk that the drying unit 60 will malfunction. On the other hand, by making the air volume F2 of the blower fan 63 greater than zero, it is possible to suppress the heat from accumulating in the heating chamber HR and causing the drying unit 60 to malfunction.

[0048] Also, in the printing apparatus 1, when performing the cutting operation, the medium M is conveyed (pulled back) from the drying area DA to the printing area PA on the upstream side in the conveyance direction from the drying area DA (see FIG. 5C). That is, when performing the cutting operation, the medium M passes between the drying area DA and the printing area PA in the conveyance direction. At the position between the drying area DA and the printing area PA in the conveyance direction, air (air curtain) is jetted from the air curtain fan 65 (air injection port 68) toward the medium M. The air jetted from this air curtain fan 65 is taken in from the outside air and has a lower temperature than the drying area DA (drying passage DR). Therefore, by jetting low-temperature air (air curtain) during the process of pulling back the medium M from the drying area DA to the printing area PA, the temperature of the medium M decreases and its expansion and contraction are suppressed. Therefore, it is possible to more easily suppress the displacement during the cutting operation.

[0049] Also, in the printing apparatus 1, the conveyance unit 30 conveys the medium M so that the medium M bends downward from the printing area PA toward the drying area DA. Since the direction in which the medium M is conveyed bends downward, it becomes easier to secure the space of the conveyance path compared to the case where the medium M is conveyed straight horizontally. And it becomes easier to arrange the drying unit 60 on the downstream side in the conveyance direction of the printing area PA. Incidentally, if the medium M is excessively heated even during the cutting operation after the image is dried, the medium M will harden, and it will be difficult for the medium M to bend along the conveyance path, and the medium M may float up from the platen 4B or the front apron 4C during conveyance, or there may be fluttering during conveyance. On the other hand, according to the printing apparatus 1, since the heating of the medium M during the cutting operation is suppressed, the medium M is difficult to harden and it is easy to bend the medium M along the conveyance path. Therefore, even if the conveyance path (conveyed direction) of the medium M bends downward, the above-mentioned problems are less likely to occur.

[0050] ===Second Embodiment=== In the second embodiment, a printing apparatus 2 having a different configuration of the drying unit 60 from the printing apparatus 1 according to the first embodiment will be described. FIG. 8 is a schematic cross-sectional view for explaining the printing apparatus 2.

[0051] In the printing apparatus 2, the components other than the drying unit 60 are substantially the same as those in the printing apparatus 1. Therefore, the description of the components other than the drying unit 60 is omitted. In the printing apparatus 2, in the drying area DA (the area where the drying unit 60 was arranged in the printing apparatus 1), a platen heater 69 is provided along the front apron 4C. The platen heater 69 is a plate-shaped heater and can heat the medium M supported on the front apron 4C by being controlled in the same manner as the heater 61 of the printing apparatus 1 by the controller 10 (see FIG. 7A).

[0052] The printing operation of the printing apparatus 2 in the second embodiment is carried out in substantially the same manner as the printing operation of the printing apparatus 1 in the first embodiment (see FIG. 4). However, in the printing apparatus 2, in the drying step (S103), the medium M is heated and dried by the above-described platen heater 69. Specifically, similar to the heater 61 described with reference to FIG. 7A, in the conveying step (S101) and the image forming step (S102), the platen heater 69 is turned off, and in the drying step (S103), the calorific value of the platen heater 69 is controlled to be H1. Then, in the cutting step (S104), the calorific value of the platen heater 69 is controlled to be H2 which is smaller than H1 (H1 > H2).

[0053] By reducing the calorific value (H2) of the platen heater 69 during the cutting operation compared to the calorific value (H1) of the platen heater 69 during the drying operation, it is possible to prevent the medium M from being overheated.

[0054] ===Third Embodiment === In the above-described first and second embodiments, the cutting step (S104) was performed after the image forming step (S102) and the drying step (S103). However, as will be described below, the image forming step or the drying step may be performed after the cutting step.

[0055] FIG. 9 is a flowchart of the printing operation according to the third embodiment using the printing apparatus 1. FIGS. 10A to 10D are diagrams for explaining the operations of the respective parts of the printing apparatus 1 during the printing operation according to the third embodiment.

[0056] First, a cutting step of cutting a predetermined area of the medium M is performed (S202). In the cutting step, a cutting operation of cutting using the cutting unit 50 is performed. As shown in FIG. 10A, while moving the medium M along the conveyance direction, the cutter 51 is reciprocated in the scanning direction to cut the medium M. Note that "cutting" includes both the case of cutting the entire thickness direction of the medium M (for example, when cutting both the mount and the release paper of the medium M composed of the mount and the release paper) and the case of cutting a part of the thickness direction of the medium M (for example, when the mount is not cut in the entire thickness direction and the release paper is cut in the entire thickness direction). Here, a part of the thickness direction of the medium M is cut. FIG. 10A shows the cut line formed on the medium M by the cutter 51. Here, the cut line is formed along the contour of the image A described later.

[0057] Next, an image forming step of forming an image on the medium is performed (S203). In the image forming step, as shown in FIG. 10B, the medium (the medium on which the cut line is formed) located downstream of the printing area in the conveyance direction is conveyed from the downstream side to the upstream side in the conveyance direction and pulled back to the area where the image is to be printed. Then, as shown in FIG. 10C, while reciprocating the carriage 21 in the scanning direction, an image forming operation is performed in which ink is ejected from the ink head 41 mounted on the carriage 21 and ink droplets land on the medium M. Note that the image is printed on the medium M by alternately repeating the image forming operation and the operation of conveying the medium M from the upstream side to the downstream side in the conveyance direction. FIG. 10C shows a state in which the image A is formed on the medium M on which the cut line is formed while moving the ink head 41 in the scanning direction in the printing area PA.

[0058] Next, a drying process is performed to dry and fix the image (ink droplets) formed on the medium (S204). As shown in FIG. 10D, in the drying process, the image A formed on the medium is conveyed to a drying region DA on the downstream side in the conveyance direction from the printing region PA and dried by the drying unit 60.

[0059] FIGS. 11A and 11B are diagrams for explaining a control method for each part of the drying unit 60 in the third embodiment. FIG. 11A is a diagram for explaining a control method for the calorific value (heating temperature) of the heater 61 in the third embodiment. FIG. 11B is a diagram for explaining a control method for the air volume of the blower fan 63 in the third embodiment.

[0060] In the cutting process (S202) of the third embodiment, control is performed so as to weaken the operation of each part of the drying unit 60. The controller 10 (control unit) controls the calorific value of the heater 61 to be H2, which is smaller than H1, as shown in FIG. 11A. That is, the calorific value (H2) of the heater 61 during the cutting operation is controlled to be decreased compared to the calorific value (H1) of the heater 61 during the drying operation (H1 > H2). By decreasing the calorific value of the heater 61, it is possible to suppress the medium M from being overheated. Since it takes a predetermined time to raise the heater 61 to the drying temperature, it is preferable not to turn off the heater 61.

[0061] Also, in the cutting step (S202) of the third embodiment, the controller 10 (control unit) controls the air volume of the blower fan 63 to be F2, which is smaller than F1, as shown in FIG. 11B. That is, the controller controls the blower fan motor 64 so as to reduce the air volume (F2) of the blower fan 63 during the cutting operation compared to the air volume (F1) of the blower fan 63 during the drying operation (F1 > F2). By reducing the air volume of the blower fan 63, the total amount of heat sent to the medium M by the wind is reduced, so that the medium M is prevented from being overheated. Note that the blowing by the blower fan 63 may be stopped, but if the blower fan 63 is stopped, the temperature of the heater 61 may become too high. Therefore, when stopping the blower fan 63, it is necessary to perform fine control such as repeating on / off to prevent the temperature of the heater 61 from becoming too high. For this reason, rather than stopping the blower fan 63, it is preferable not to turn off the blower fan 63 in order to prevent the heater 61 from becoming too high.

[0062] In the image forming step (S203) of the third embodiment, the controller 10 (control unit) controls each part of the drying unit 60 in the same manner as during the drying operation, as shown in FIGS. 11A and 11B. When the image formed on the medium M is long in the conveyance direction, a part of the image may reach the drying area DA during the printing of the image. Therefore, by controlling each part of the drying unit 60 in the same manner as during the drying operation during the image forming step, it becomes possible to dry the image in the drying area DA while forming the image on the medium M in the printing area PA.

[0063] Figs. 12A to 12C are explanatory views of the medium M in the third embodiment. Fig. 12A is an explanatory view of the medium M after the cutting step (S202) and before the image forming step (S203). Fig. 12A shows that a cut line is formed on the medium M. Fig. 12B is an explanatory view of the medium M after the image forming step (S203) and after the drying step (S204). Fig. 12B shows that a cut line and an image are formed on the medium M. Fig. 12C is an explanatory view of the medium M after the drying step (S204). Fig. 12C shows that the medium M has shrunk due to the drying process.

[0064] In the third embodiment, when performing the cutting operation, the controller 10 (control unit) executes control to weaken the operation of each part of the drying unit 60 as compared with the drying operation. For this reason, as shown in Fig. 12C, when the drying operation is performed, the medium M shrinks, whereas when the cutting operation is performed as shown in Fig. 12A, shrinkage of the medium M can be suppressed. Further, in the third embodiment, even when the medium M shrinks when the drying operation is performed as shown in Fig. 12C, since the cut line and the image shrink together, displacement between the cut line and the image can be suppressed.

[0065] Figs. 13A to 13C are explanatory views of the medium M in the comparative example. In the comparative example, the printing operation is executed in the order of the image forming step, the drying step, and the cutting step. Fig. 13A is an explanatory view of the medium M after the image forming step and before the drying step. Fig. 13B is an explanatory view of the medium M after the drying step and before the cutting step. Fig. 13C is an explanatory view of the medium M after the cutting step. In the comparative example, when the medium M is heated to dry the ink, the medium M shrinks, and then the cutting step is executed. As shown in Fig. 13C, in the comparative example, since cutting is performed after the medium has shrunk, there is a possibility that the cut line set before printing may be displaced with respect to the image to be actually printed. For this reason, when the printing operation is executed in the order of the image forming step, the drying step, and the cutting step as in the comparative example and the thermal shrinkage of the medium M is large, it is necessary to correct the displacement of the cut line generated due to the thermal shrinkage with respect to the cut line set before the printing setting.

[0066] In the third embodiment, when performing the cutting operation, the controller 10 (control unit) executes control to weaken the operation of each part of the drying unit 60 compared to the drying operation, so that the medium M can be prevented from being overheated during the cutting operation. Therefore, it is possible to suppress the deviation between the cut line set before printing and the image during printing (when discharging ink). That is, when the printing operation is executed in the order of the cutting step, the image forming step, and the drying step as in the third embodiment, even if the thermal contraction of the medium M is large, since the cut line and the image contract together, the deviation between the cut line and the image can be suppressed. Therefore, it is not necessary to correct the deviation of the cut line according to the contraction of the medium.

[0067] Note that in FIGS. 11A and 11B, the controller 10 (control unit) weakens the heating of the medium M by controlling the heater 61 and the blower fan 63 (blower fan motor 64) respectively. However, the heating of the medium M may be weakened by controlling at least one of the heater 61 and the blower fan 63 as described above. For example, it may be controlled to reduce only the calorific value of the heater 61 during the cutting operation compared to the drying operation, and not change the control of the blower fan 63. Also, when the drying unit 60 is constituted by the platen heater 69 as in the second embodiment, the controller 10 (control unit) may reduce the calorific value of the platen heater 69 when performing the cutting operation, with the calorific value of the platen heater 69 when performing the drying operation being H1 and the calorific value of the platen heater 69 when performing the cutting operation being H2 (H1 > H2).

[0068] ===Other Embodiments=== The above embodiments are presented as examples and do not limit the scope of the invention. The above configurations can be implemented in appropriate combinations, and various omissions, replacements, and changes can be made without departing from the gist of the invention. The above embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and its equivalent scope.

Explanation of Reference Numerals

[0069] 1 Printing device (First Embodiment), 2 Printing device (Second Embodiment), 4A Rear apron, 4B Platen, 4C Front apron, 5 Stand, 10 Controller (Control unit), 20 Carriage unit, 21 Carriage, 22 Carriage motor, 23 Position detection unit, 30 Conveyor unit, 31A Conveyor roller, 31B Pinch roller, 32 Conveyor motor, 33 Conveyor detection unit, 40 Printing unit, 41 Ink head, 42 Head drive unit, 50 Cutting unit, 51 Cutter, 52 Cutter solenoid, 60 Drying unit, 61 Heater, 62 Heater drive unit, 63 Blower fan, 64 Blower fan motor, 65 Air curtain fan, 66 Air curtain motor, 67 Casing, 671 Outer casing, 672 Inner casing, 672i Heat inlet, 672e Heat outlet, 673 Partition wall, 674 Heating chamber partition wall, 68 Air injection port, 69 Platen heater, M Medium, PA Printing area, DA Drying area

Claims

1. A transport unit that transports a medium in a transport direction, an ink head that discharges ink onto the medium to form an image, a drying unit that includes a heater that generates heat and dries the ink discharged onto the medium, a cutting unit that cuts a portion of the medium on which an image has been formed, a control unit, and a printing apparatus having the same, wherein the drying unit includes a blower fan that blows the heat toward the medium, when performing a cutting operation by the cutting unit, the control unit, compared to when drying the ink, reduces the amount of heat generated by the heater, reduces the amount of air blown by the blower fan, and executes at least one of the above controls. A printing apparatus characterized by this.

2. A printing apparatus according to Claim 1, wherein the control unit performs a cutting operation by the cutting unit after an image forming operation by the ink head. A printing apparatus characterized by this.

3. A printing apparatus according to Claim 2, wherein the drying unit further includes an air curtain fan that forms an air curtain that suppresses the heat from escaping outside the drying unit by injecting air toward the medium at an upstream position in the transport direction of the drying unit, when performing a cutting operation by the cutting unit after an image forming operation by the ink head, the control unit, reduces the amount of heat generated by the heater, reduces the amount of air blown by the blower fan, increases the amount of air injection by the air curtain fan, and executes at least one of the above controls. A printing apparatus characterized by this.

4. A printing apparatus according to Claim 3, wherein in the transport direction, a printing area where the image forming operation and the cutting operation are performed and a drying area where a drying operation by the drying unit is performed are provided, the drying area is located downstream of the printing area in the transport direction, and when performing the cutting operation, the medium is transported from the drying area to the printing area. A printing apparatus characterized by this.

5. A printing apparatus according to Claim 4, wherein the transport unit transports the medium so that the medium bends downward from the printing area toward the drying area. A printing apparatus characterized by this.

6. A printing apparatus according to any one of Claims 1 to 5, when performing a cutting operation by the cutting unit after an image forming operation by the ink head, The printing apparatus is characterized in that the control unit executes control so that the calorific value of the heater and the air volume of the blower fan are greater than zero.

7. The printing apparatus according to claim 1, wherein the control unit performs an image forming operation by the ink head after a cutting operation by the cutting unit.

8. a conveyance unit that conveys a medium in a conveyance direction; an ink head that discharges ink onto the medium to form an image; a drying unit that includes a heater that generates heat and dries the ink discharged onto the medium; a cutting unit that cuts a portion where an image is formed from the medium; a control unit; The printing apparatus having: when performing a cutting operation by the cutting unit, the control unit executes control to reduce the calorific value of the heater compared to when drying the ink.

Images