JP2024029342A - Processing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a processing device which enables reduction of a thickness of an adhering object adhering to a sheet and enables a surface of the adhering object to be flattened to provide glossy feeling to a processed part of the sheet.

SOLUTION: A processing device includes: a printing cylinder 16 (a transport device) which transports a sheet 4, holding the sheet 4; first to fourth inkjet heads 22 to 25 which perform processing to a processed surface of the sheet 4 held by the printing cylinder 16; ink drying means 27 (a processed device body); and first and second pressing cylinders 41, 48 (pressing means) which are provided at the downstream side of the ink drying means 27 in a sheet 4 transport direction and press the processed surface of the sheet 4.

SELECTED DRAWING: Figure 1

COPYRIGHT: (C)2024,JPO&INPIT

Description

The present invention relates to a processing apparatus equipped with a pressing means for pressing a sheet.

2. Description of the Related Art Conventionally, processing apparatuses for attaching some kind of substance to sheets include printing apparatuses such as inkjet printing apparatuses and offset printing apparatuses, and coating apparatuses for applying varnish. An example of an inkjet printing device is one described in Patent Document 1, for example.
The inkjet printing device disclosed in Patent Document 1 includes first to fourth inkjet heads that eject ink onto a sheet, and a drying device provided downstream of these first to fourth inkjet heads in the conveying direction of the sheet. It is equipped with
The drying device consists of an ink drying lamp. Ink is dried (cured) by being irradiated with infrared rays or ultraviolet rays from an ink drying lamp.

JP 2017-210337 Publication

In the inkjet printing apparatus disclosed in Patent Document 1, infrared rays and ultraviolet rays are irradiated from an ink drying lamp immediately after ink is ejected onto a sheet. For this reason, there is a problem that the ink hardens before it soaks into the sheet, resulting in a thicker ink film than in general offset printing. This problem becomes more noticeable when UV-curable ink is used for printing. There are two reasons for this. The first reason is that UV-curable ink has a higher viscosity than other inks such as oil-based inks and is difficult to penetrate into a sheet of paper. The second reason is that UV-curable ink has a much faster curing speed than oil-based ink.

If the ink film is thick, processing will be hindered when some processing is performed on the sheet in a subsequent process. That is, a thick ink film leads to a decrease in workability in post-processing. Further, when the patterns are concentrated in some areas, the pattern parts become partially raised, which causes a problem that the sheets cannot be stacked evenly.
Furthermore, as the ink film becomes thicker, the smoothness of the ink surface decreases and light is diffusely reflected, resulting in the problem that the printed area has a weaker gloss than offset printing. In particular, in halftone areas, ink is scattered with respect to solid areas, and light is likely to be diffusely reflected, so that the gloss becomes even weaker. Such a problem also occurs in offset printing apparatuses, coating apparatuses, etc., which are common to inkjet printing apparatuses in that they perform a process of causing deposits to adhere to the processed surface of the sheet.

An object of the present invention is to provide a processing device that can reduce the thickness of deposits adhering to a sheet, smooth the surface of the deposits, and impart a glossy appearance to the processed portion of the sheet. That's true.

In order to achieve this object, a processing apparatus according to the present invention includes a transporting apparatus that holds and transports a sheet, a processing apparatus main body that processes a processing surface of a sheet held by the transporting apparatus, and a processing apparatus main body that processes a processing surface of a sheet held by the transporting apparatus. The apparatus is provided with a pressing means that is provided on the downstream side in the conveying direction of the sheet and presses the processing surface of the sheet. The term "processing" used herein includes printing such as inkjet printing and offset printing, and coating such as varnishing.

In the processing apparatus according to the present invention, the processing apparatus main body includes a plurality of print heads that eject ink onto the processing surface of the sheet held by the conveyance apparatus, and a plurality of print heads provided downstream from the print heads in the sheet conveyance direction. , and an ink drying device that dries the ink adhered to the sheet.

In the present invention, the processing device is configured to be capable of performing double-sided printing in which both the front and back sides of the sheet serve as printing surfaces, and single-sided printing in which one side of the sheet serves as the printing surface; The first pressing means presses one printing surface of the sheet when printing on both sides, and the second pressing means presses the other printing surface of the sheet during duplex printing and presses the printing surface of the sheet during single-sided printing. It's okay.

In the present invention, the processing apparatus further includes a control device configured to switch to either one of one-sided printing or double-sided printing, and a control device located downstream of the ink drying device in a sheet conveyance direction. a conveyance path switching means for switching the conveyance destination of the sheet according to the print mode of the sheet, and the conveyance destination of the sheet by the conveyance path switching means is one side of the sheet when the print mode of the control device is a double-sided printing mode. a reversing mechanism for reversing the front and back of the sheet and returning it to the conveying device when printing has been completed only on one side; It may also be a paper ejecting mechanism that ejects the sheet when the sheet is finished.

In the present invention, in the processing apparatus, the first pressing means may be provided in the reversing mechanism, and the second pressing means may be provided in the paper ejecting mechanism.

In the present invention, in the processing apparatus, the first pressing means and the second pressing means may be provided in the paper ejection mechanism.

In the processing apparatus according to the present invention, the reversing mechanism includes a reversing side transfer drum that receives the sheet from the conveying path switching means, a front reversing cylinder that receives the sheet from the reversing side transferring drum, and a sheet being conveyed to the front reversing cylinder. and a reversing means for holding the tail of the sheet and returning it to the conveying device.

In the processing apparatus according to the present invention, the paper discharge mechanism includes a first paper discharge side transfer cylinder that receives the sheet from the conveyance path switching means, and a second paper discharge side transfer cylinder that receives the sheet from the first paper discharge side transfer cylinder. It may be comprised of a paper discharge side transfer cylinder and a paper discharge means for receiving the sheet from the second paper discharge side transfer cylinder and discharging the sheet.

According to the present invention, the deposits raised on the processed surface of the sheet are pushed by the pressing means and pushed into the sheet, so that the thickness of the deposits can be reduced. Furthermore, since the surface of the deposit becomes smooth, it becomes possible to impart a glossy appearance to the treated portion of the sheet.

FIG. 1 is a side view of a printing apparatus according to a first embodiment. FIG. 2 is a side view of the reversing mechanism. FIG. 3 is a side view of the paper ejection mechanism. FIG. 4 is a block diagram showing the configuration of the control system. FIG. 5 is a side view of the printing device according to the second embodiment. FIG. 6 is a side view of the paper ejection mechanism. FIG. 7 is a side view showing a part of the printing apparatus according to the third embodiment. FIG. 8 is a side view of the printing apparatus according to the fourth embodiment. FIG. 9 is a side view of the printing apparatus according to the fifth embodiment. FIG. 10 is a side view of the coating apparatus according to the sixth embodiment.

(First embodiment)
Hereinafter, one embodiment of the processing apparatus according to the present invention will be described in detail with reference to FIGS. 1 to 4. Here, an embodiment in which the present invention is applied to an inkjet printing device will be described.
A printing apparatus 1 shown in FIG. 1 conveys a sheet 4 from a feeder section 2 located on the far right in FIG. 1 to a printing unit 3, and prints on one or both sides of the sheet 4 in this printing unit 3. In this embodiment, the printing side when printing on one side of the sheet 4 and the printing side that is first printed when printing on both sides of the sheet 4 are referred to as the "front side" of the sheet 4, and the side opposite to the front side is referred to as the "front side" of the sheet 4. is called the "back side".
The sheet 4 that has been printed by the printing unit 3, that is, the sheet 4 on which only the front side is printed, or the sheet 4 on which both the front and back sides are printed, is processed by the printing unit 3 as described below. It is sent to the delivery section 6 via the discharge cylinder 5 and accumulated in the delivery pile 7.

The feeder section 2 has a structure in which the sheets 4 are transferred from the feeder pile 11 to the feeder board 12 by means of a sucker (not shown). A soccer game operates in one of two modes: a mode in which the sheets 4 are fed continuously, and a mode in which the sheets 4 are fed intermittently. When printing is performed only on the front side of the sheet 4, that is, in the case of single-sided printing, the sucker continuously feeds the sheet 4 to the feeder board 12. On the other hand, when printing is performed on the front and back sides of the sheet 4, that is, in the case of double-sided printing, the sucker feeds the sheet 4 to the feeder board 12 intermittently. Such soccer movements are controlled by a control device 13 (see FIG. 4), which will be described later.

(Description of printing unit)
The printing unit 3 includes a supply cylinder 15 to which the sheet 4 supplied from the feeder section 2 is conveyed by a swing device 14, a printing cylinder 16 to which the sheet 4 is conveyed from the supply cylinder 15, and the sheet 4 after printing, which will be described later. A discharge cylinder 5 is provided as a conveyance path switching means for distributing the paper to either one of the reversing mechanism 17 and the paper discharge mechanism 18.
The supply cylinder 15 has a first gripping device 21 that holds the sheet 4 . The first gripper device 21 grips and holds the downstream end 4a of the sheet 4 in the transport direction, and supplies the sheet 4 received from the swing device 14 to the printing cylinder 16 at the supply position P1.

The printing cylinder 16 constitutes a "conveying device" in the present invention, and absorbs the sheet 4 and conveys it to a position where printing is performed by first to fourth inkjet heads 22 to 25, which will be described later. The printing cylinder 16 according to this embodiment is a so-called triple cylinder, and is provided with second gripping claw devices 26 at three locations in the rotational direction. The second gripper device 26 is equivalent to the first gripper device 21 provided on the supply cylinder 15.

A plurality of first to fourth inkjet heads 22 to 25 and an ink drying means 27 are arranged in this order near the periphery of the printing cylinder 16 and downstream from the supply cylinder 15 in the conveying direction of the sheet 4. ing. The first to fourth inkjet heads 22 to 25 and the ink drying means 27 constitute a "processing device main body" in the present invention. The first to fourth inkjet heads 22 to 25 constitute "a plurality of print heads" in the present invention. The first to fourth inkjet heads 22 to 25 are connected to the printing surface of the sheet 4 held on the printing cylinder 16 (the surface opposite to the conveying surface that contacts the printing cylinder, and referred to as the "processing surface" in the present invention). Printing is performed by ejecting ink onto the surface. The operations of the first to fourth inkjet heads 22 to 25 are controlled by a control device 13, which will be described later.

The ink drying means 27 corresponds to the "ink drying device" in the present invention, is provided downstream from the fourth inkjet head 25 in the conveying direction of the sheet 4, and dries the ink adhering to the sheet 4. The ink drying means 27 can be constituted by, for example, an ink drying lamp. The ink drying lamp irradiates the sheet 4 with infrared rays and ultraviolet rays. Ink dries or hardens by being irradiated with infrared rays or ultraviolet rays. In the printing apparatus 1 according to this embodiment, the ink is completely dried or hardened by the sheet 4 passing near the ink drying lamp.

The discharge cylinder 5 receives the printed sheet 4 from the printing cylinder 16 at a receiving position P2 located downstream of the ink drying means 27 in the conveyance direction of the sheet 4, and depending on the printing state of the sheet 4, a reversing mechanism 17 (described later) and the paper ejecting mechanism 18 for conveyance. The printing state is a state in which printing is performed on one side of the sheet 4 and a state in which printing is performed on both sides of the sheet 4.
The delivery cylinder 5 receives the sheet 4 from the printing cylinder 16 and transfers the sheet 4 to the reversing mechanism 17 and the paper delivery mechanism 18 using a third gripper device 31 provided on the delivery cylinder 5. After holding the downstream end 4a of the sheet 4 in the conveying direction at the receiving position P2, the third gripping claw device 31 is controlled by the control device 13 to move either the reversing mechanism 17 or the paper ejecting mechanism 18. It operates so that the sheet 4 is delivered to one of the destinations. A configuration for the discharge cylinder 5 to switch the conveyance destination of the sheet 4 can be realized using, for example, a switching mechanism described in Patent Document 1. The operation of the discharge cylinder 5 when switching the conveyance destination is controlled by a control device 13, which will be described later.

(Explanation of reversing mechanism)
As shown in FIG. 2, the reversing mechanism 17 includes a reversing side transfer drum 33 which receives the sheet 4 from the discharge cylinder 5 by a fourth gripper device 32, and a reversing side transfer drum 33 which receives the sheet 4 from the reversing side transfer drum 33 through a fifth gripper. The pre-reversing doubler cylinder 35 received by the device 34 and the trailing edge (rear end 4b, which is the upstream end in the transport direction) of the sheet 4 conveyed by the pre-reverse doubler cylinder 35 are gripped by the sixth gripping claw device 36. It is constituted by a reversing swing device 37 as a reversing means for returning the printing cylinder 16 to the printing cylinder 16.
The reversing swing device 37 is configured to swing around an axis parallel to the axes of the printing cylinder 16 and the pre-reversing double cylinder 35, and the sixth gripping claw device 36 provided at the swinging end It swings back and forth between a position close to the pre-reversal double cylinder 35 and a sheet return position P3 close to the printing cylinder 16. The reversing swing device 37 swings toward the printing cylinder 16 with the sixth gripping claw device 36 of the reversing swing device 37 gripping the paper trailing edge of the sheet 4 on the pre-reversing double cylinder 35 side. The front and back sides are reversed, and this sheet 4 is delivered to the printing cylinder 16 at the sheet return position P3.

The reversing side transfer cylinder 33 has an outer circumferential surface 33a with which the entire print area of the sheet 4 is in close contact. The outer peripheral surface 33a is formed of a metal material or other highly rigid material. Moreover, the surface of the outer circumferential surface 33a is formed smoothly. The sheet 4 conveyed by the reversing side transfer cylinder 33 is printed on both the front and back sides, and the sheet 4 is printed on the front side, and is transferred to the reversing side with the printed side (front side) exposed. It is held by the transfer body 33.

A first pressing cylinder 41, which constitutes the first pressing means of the present invention, is arranged at a position facing the sheet 4 conveyed by the reversing side transfer cylinder 33. The first pressing cylinder 41 presses the sheet 4 being conveyed by the reversing transfer cylinder 33 with a predetermined pressing force. This pressing force is 4 to 12 times the printing pressure in offset printing. The first pressing cylinder 41 is a rotary cylinder whose entire outer circumferential surface 41a is smoothly formed, and whose axis is parallel to the axis of the reversing side transfer cylinder 33, and whose outer circumferential surface 41a is connected to the reversing side transfer cylinder 33. It is rotatably supported by a printing device frame (not shown) via a bearing structure 42 while being in contact with the outer circumferential surface 33a of the printer. The bearing structure 42 has a configuration in which the distance between the shafts of the first pressing cylinder 41 and the reversing side transfer cylinder 33 can be adjusted. An example of a structure for adjusting the distance between the shafts is an eccentric bearing. By adjusting the distance between the axes, the pressing force when the first pressing cylinder 41 presses the sheet 4 can be adjusted. The outer diameter of the first pressing cylinder 41 according to this embodiment is approximately the same diameter as that of the reversing side transfer cylinder 33, which is a single cylinder.

The first pressing cylinder 41 rotates as the sheet 4 is conveyed while pressing the sheet 4. Note that the first press cylinder 41 is not limited to the configuration in which it rotates by co-rotation in this way. There is no limit to the method of driving the first press cylinder 41, and for example, the first press cylinder 41 may be driven independently to rotate, or the first press cylinder 41 may be rotated by transmitting power for driving the reversing side transfer cylinder 33. I can do it.

The outer circumferential surface 41a of the first press cylinder 41 is formed of an elastic body. As this elastic body, for example, a rubber material such as silicone rubber or synthetic rubber, an elastomer, or a plastic material having elasticity can be used. Note that this outer circumferential surface 41a may be formed of a metal material in order to press the sheet 4 even more strongly.

(Explanation of paper ejection mechanism)
As shown in FIG. 3, the paper ejection mechanism 18 includes a first paper ejection side transfer cylinder 44 that receives the sheet 4 from the ejection cylinder 5 by a seventh gripper device 43, and a first paper ejection side transfer cylinder 44 that receives the sheet 4 from the ejection cylinder 5. A second paper delivery side transfer cylinder 46 that receives the sheet 4 by the eighth gripping claw device 45, and a paper delivery unit that conveys the sheet 4 ejected from the second paper delivery side transfer cylinder 46 to the delivery section 6. It is composed of a discharge belt 47 and the like.

The first paper delivery side transfer cylinder 44 has an outer circumferential surface 44a with which the entire print area of the sheet 4 is in close contact. This outer peripheral surface 44a is formed of a metal material or other highly rigid material. The outer peripheral surface 44a has a smooth surface. The sheet 4 conveyed by the first paper delivery side transfer cylinder 44 may be printed on only one side, or printed on both the front and back sides, and the sheet may be printed on only one side. The printing surface (front surface) of the sheet 4 and the second printing surface (back surface) of the sheet 4 on which both the front and back sides are printed are held on the first paper delivery side transfer cylinder 44 in an exposed state.

A second pressing cylinder 48, which constitutes the second pressing means of the present invention, is arranged at a position facing the sheet 4 conveyed by the first paper delivery side transfer cylinder 44. The second press cylinder 48 according to this embodiment is arranged directly above the first paper delivery side transfer cylinder 44 . The second pressing cylinder 48 has the same configuration as the first pressing cylinder 41 described above, and presses the sheet 4 being conveyed by the first paper delivery side transfer cylinder 44 with a predetermined pressing force. This pressing force is 4 to 12 times the printing pressure in offset printing.
The second press cylinder 48 has a smooth outer circumferential surface 48a like the first press cylinder 41, and its axis is parallel to the axis of the first paper delivery side transfer cylinder 44 and is located on the first paper delivery side. It is rotatably supported by a printing device frame (not shown) via a bearing structure 49 while being in contact with the outer circumferential surface 44a of the transfer cylinder 44. The bearing structure 49 has a configuration in which the distance between the axes of the second press cylinder 48 and the first paper delivery side transfer cylinder 44 can be adjusted. An example of a structure for adjusting the distance between the shafts is an eccentric bearing. By adjusting the distance between the axes, the pressing force when the second pressing cylinder 48 presses the sheet 4 can be adjusted. The outer diameter of the second press cylinder 48 according to this embodiment is approximately the same diameter as the first paper delivery side transfer cylinder 44, which is a single cylinder.

The second pressing cylinder 48 rotates as the sheet 4 is conveyed while pressing the sheet 4. Note that the second press cylinder 48 is not limited to the configuration in which it rotates by co-rotation in this way. There is no limit to the method of driving the second press cylinder 48, and for example, the second press cylinder 48 may be driven independently to rotate, or the power to drive the first paper delivery side transfer cylinder 44 may be transmitted to rotate the second press cylinder 48. configuration can be adopted.
The outer circumferential surface 48a of the second press cylinder 48 is formed of an elastic body. As the elastic body, for example, rubber materials such as silicone rubber and synthetic rubber, elastomers, and plastic materials having elasticity can be used.

The discharge belt 47 is an endless belt, and is stretched between an upstream sprocket 47a located near the bottom of the second paper delivery side transfer drum 46 and a downstream sprocket 47b located above the delivery pile 7. It extends substantially horizontally from near the bottom of the paper discharge side transfer cylinder 46 of No. 2 to the side opposite to the printing cylinder 16. This discharge belt 47 is rotated by driving an upstream sprocket 47a and a downstream sprocket 47b together with the printing cylinder 16 and other cylinders by a drive device (not shown). The sheet 4 is placed on a discharge belt 47, and is conveyed to the delivery section 6 as the discharge belt 47 moves (rotates).

(Description of control device)
The control device 13 is composed of a CPU (Central Processing Unit), and as shown in FIG. 4, a print mode selection switch 51 and a rotary encoder 52 as a phase detection device are connected, and The fourth inkjet heads 22 to 25, the sucker operation switching actuator 53 of the feeder section 2, the transport path switching actuator 54 of the discharge cylinder 5, and the like are connected. The print mode selection switch 51 is used to switch the printing apparatus 1 between a one-sided printing mode in which one-sided printing is performed and a two-sided printing mode in which two-sided printing is performed.

When the single-sided printing mode is selected by the print mode selection switch 51, the control device 13 controls the feeder section 2 (soccer operation switching actuator 53), the first to fourth inkjet heads 22 to 25, and the like to perform single-sided printing. Controls the operation of the discharge cylinder 5 (transport route switching actuator 54), etc. Further, when the double-sided printing mode is selected by the print mode selection switch 51, the control device 13 controls the feeder section 2 (soccer operation switching actuator 53), the first to fourth inkjet heads 22 to 25, the discharge cylinder 5 (transport route switching actuator 54), and the like.

(Explanation of operation when printing on one side)
Next, the operation of the printing apparatus 1 according to this embodiment will be explained.
When an operator (not shown) operates the print mode selection switch 51 to select single-sided printing mode, the control device 13 is switched to the single-sided printing mode and controls the operations of various devices. In the single-sided printing mode, the sheets 4 are continuously fed from the feeder section 2 to the printing unit 3. The sheet 4 conveyed to the printing cylinder 16 of the printing unit 3 is printed by passing near the first to fourth inkjet heads 22 to 25. Printing is performed by the control device 13 specifying the position of the sheet 4 based on the phase signal of the rotary encoder 52.

The ink printed on the sheet 4 is cured as the sheet 4 is conveyed near the ink drying means 27.
Thereafter, the sheet 4 is sent from the print cylinder 16 to the discharge cylinder 5. In the single-sided printing mode, the sheet 4 held on the discharge cylinder 5 is sent to the first paper delivery side transfer cylinder 44 of the paper delivery mechanism 18 without being sent to the reversing mechanism 17 . This sheet 4 is pressed by a second pressing cylinder 48 while being conveyed by the first paper delivery side transfer cylinder 44 .
At this time, the second pressing cylinder 48 presses the printing surface (front surface) of the sheet 4. The hardened ink adheres to the printing surface of the sheet 4 in a raised state from the surface of the sheet 4.

This ink is pushed into the interior of the sheet 4 by being pressed against the outer circumferential surface 48a of the second press cylinder 48. Therefore, the film thickness of the ink exposed on the surface of the sheet 4 can be reduced. The film thickness of the ink exposed on the surface of the sheet 4 is 5 μm to 10 μm before pressing, but becomes approximately 1 μm after pressing.
Further, the ink is pressed by the second press cylinder 48, so that the surface of the ink becomes smooth, and a glossy appearance is imparted to the printed portion on the surface of the sheet 4.
The sheet 4 that has passed between the first paper delivery side transfer cylinder 44 and the second press cylinder 48 is transferred to the second paper delivery side transfer cylinder 46 and from the second paper delivery side transfer cylinder 46. It is discharged onto the discharge belt 47, discharged above the delivery pile 7 by the discharge belt 47, and stacked on the delivery pile 7.

(Explanation of operation during double-sided printing)
When the operator operates the print mode selection switch 51 to select the double-sided printing mode, the control device 13 controls the operations of various devices in the double-sided printing mode. In the double-sided printing mode, the sheet 4 is intermittently supplied from the feeder section 2 to the printing unit 3. That is, the sheet 4 is conveyed to the printing cylinder 16 every two rotations of the supply cylinder 15. The new sheet 4 thus conveyed to the printing cylinder 16 is conveyed by the printing cylinder 16, has its surface printed, and is sent to the discharge cylinder 5, as in the case of single-sided printing.

In the double-sided printing mode, a new sheet 4 whose surface is printed is transferred from the discharge cylinder 5 to the reversing side transfer cylinder 33. The sheet 4, which has been printed only on its surface, is pressed by the first pressing cylinder 41 while being conveyed by the reversing side transfer cylinder 33. At this time, the first pressing cylinder 41 presses the surface of the sheet 4, which is the printing surface. The hardened ink adheres to the printing surface of the sheet 4 in a raised state from the surface of the sheet 4. This ink is pushed into the interior of the sheet 4 by being pressed against the outer circumferential surface of the first press cylinder 41 . Therefore, in the same way as when the sheet 4 is pressed by the second press cylinder 48 during single-sided printing, the thickness of the ink film exposed on the surface of the sheet 4 can be reduced, and the ink surface can be smoothed. , a glossy appearance is imparted to the printed portion on the surface of the sheet 4.

The sheet 4 that has passed between the reversing side transfer drum 33 and the first pressing cylinder 41 is transferred from the reversing side transfer drum 33 to the pre-reversing doubling drum 35, and is further turned over by the reversing swing device 37 to form the back side. It is delivered to the printing cylinder 16 in a state where it is exposed. The sheet 4, which is held on the printing cylinder 16 with the back side exposed, is printed on the back side when passing near the first to fourth inkjet heads 22 to 25. At this time, the control device 13 discriminates between a new sheet 4 and a sheet 4 whose back side is exposed based on the phase signal of the rotary encoder 52, and performs printing according to each sheet 4.

The sheet 4, whose back surface is printed, passes near the ink drying means 27 and is sent to the discharge cylinder 5 with the ink cured. The discharge cylinder 5 delivers the sheet 4, which has been printed on both sides in the double-sided printing mode, to the first paper discharge side transfer cylinder 44. The destination where the sheet 4 is conveyed by the discharge cylinder 5 differs depending on the printing state of the sheet 4. That is, if the print mode of the control device 13 is double-sided printing and printing has been completed on only one side of the sheet 4, the conveyance destination is the reversing mechanism 17, and in other cases, the paper ejecting mechanism 18. It is. Other cases are when the print mode of the control device 13 is a single-sided printing mode, or when printing has been completed on both sides of the sheet 4 in a double-sided printing mode.

The sheet 4 sent from the discharge cylinder 5 to the first paper discharge side transfer cylinder 44 is pressed by the second press cylinder 48 while being conveyed by the first paper discharge side transfer cylinder 44 . That is, the second press cylinder 48 presses the ink adhering to the back surface of the sheet 4, and it is pushed into the inside of the sheet 4 in the same way as when printing on one side. Therefore, the film thickness of the ink exposed on the back surface of the sheet 4 can be reduced, and the surface of the ink becomes smooth, giving a glossy appearance to the printed portion on the back surface of the sheet 4.
The sheet 4 that has passed between the first paper delivery side transfer cylinder 44 and the second press cylinder 48 is transferred to the delivery pile 7 by the second paper delivery side transfer cylinder 46 and the discharge belt 47, as in the case of single-sided printing. is discharged.

(Explanation of effects according to embodiment)
The printing apparatus 1 according to this embodiment includes a printing cylinder 16 (conveying device) that holds and conveys the sheet 4, and a printing surface (processing surface) of the sheet 4 held by the printing cylinder 16 that performs printing (processing). First to fourth inkjet heads 22 to 25 and ink drying means 27 (processing device main body); Second press cylinders 41 and 48 (pressing means) are provided.
Therefore, the ink (deposits) raised on both the front and back sides of the sheet 4 is pushed by the first and second press cylinders 41 and 48 and pushed into the sheet 4, so that the thickness of the ink can be reduced. Furthermore, since the surface of the ink becomes smooth, it becomes possible to give a glossy appearance to the printed portion (the treated portion) of the sheet 4.

The processing apparatus main body according to this embodiment includes first to fourth inkjet heads 22 to 25 that eject ink onto the printing surface of a sheet 4 held on a printing cylinder 16, and these first to fourth inkjet heads. The ink drying device 27 is provided downstream from 22 to 25 in the conveyance direction of the sheet 4 and dries the ink attached to the sheet 4.
For this reason, even though inkjet printing is performed, where the ink film is thicker and the gloss of the printed area tends to be weaker compared to general offset printing, it is possible to reduce the ink film thickness and print the sheet 4. It becomes possible to give the area a glossy appearance.

The printing apparatus 1 according to this embodiment is configured to be able to perform double-sided printing in which both the front and back sides of the sheet 4 serve as printing surfaces, and single-sided printing in which one side of the sheet serves as the printing surface. The printing apparatus 1 also includes a first pressing cylinder 41 (first pressing means) that presses one printing surface (front surface) of the sheet 4 during double-sided printing, and a first pressing cylinder 41 (first pressing means) that presses one printing surface (front surface) of the sheet 4 during double-sided printing. The second pressing cylinder 48 (second pressing means) presses the printing surface (front surface) of the sheet 4 during single-sided printing. Therefore, the raised ink is pushed by the first and second press cylinders 41 and 48 onto the sheet 4, so the ink film thickness can be reduced both during single-sided printing and double-sided printing. . Furthermore, since the surface of the ink becomes smooth, it becomes possible to impart a glossy feel to the printed area both during single-sided printing and double-sided printing.

The printing apparatus 1 according to this embodiment includes a control device 13 that can be switched to one of the printing modes of single-sided printing and double-sided printing, and a discharge cylinder 5 that can switch the conveyance destination of the sheet 4 according to the printing mode of the control device 13. (transport route switching means). The conveyance destination of the sheet 4 by the discharge cylinder 5 is determined by inverting the front and back of the sheet 4 when the print mode of the control device 13 is a double-sided printing mode and printing has been completed on only one side of the sheet 4. A reversing mechanism 17 that returns the sheet 4 to the printing cylinder 16 (conveying device) and discharges the sheet 4 when the print mode is one-sided printing or when printing has been completed on both sides of the sheet 4 in the printing mode two-sided printing. and a paper ejecting mechanism 18.
For this reason, when double-sided printing is performed, the sheet 4 is reversed and returned to the printing cylinder 16, so that the common first to fourth inkjet heads 22 to 25 are used for single-sided printing and double-sided printing. It can be implemented by Therefore, it is possible to realize a compact printing device in which the ink film thickness is thinner and the ink surface is flattened, giving a glossy appearance to the printed area during both single-sided printing and double-sided printing. .

In this embodiment, the first press cylinder 41 is provided in the reversing mechanism 17, and the second press cylinder 48 is provided in the paper discharge mechanism 18. Therefore, before the back side of the sheet 4 is printed, the film thickness of the ink adhering to the surface of the sheet 4 becomes thinner and the ink is flattened, so that printing on the back side is not affected by the ink on the front side. It can be performed. Therefore, it is possible to provide a printing device with high printing quality on the back side.

(Second embodiment)
The printing apparatus according to the present invention can be configured as shown in FIGS. 5 and 6. In FIGS. 5 and 6, members that are the same as or equivalent to those described with reference to FIGS. 1 to 4 are designated by the same reference numerals, and detailed description thereof will be omitted as appropriate. The printing device 61 shown in FIG. 5 is different from the printing device 1 according to the first embodiment in the configuration of the reversing mechanism 17 and the paper ejection mechanism 18, and the other configurations are different from the printing device 1 shown in the first embodiment. The same configuration as 1 is adopted.

The reversing mechanism 17 of the printing device 61 shown in FIG. 5 does not include the first press cylinder 41 compared to the first embodiment. This reversing mechanism 17 does not include the first pressing cylinder 41, and the rest of the structure is the same as that of the first embodiment.
As shown in FIG. 6, the paper discharge mechanism 18 of the printing device 61 shown in FIG. ing. In this embodiment, the first press cylinder 41 is arranged directly below the second paper delivery side transfer cylinder 46 . This first press cylinder 41 is used for a printing press (not shown) in a state in which its axis is parallel to the second paper delivery side transfer cylinder 46 and the outer circumferential surface 41a is in contact with the second paper delivery side transfer cylinder 46. It is rotatably supported on the frame by a bearing structure 42. This bearing structure 42 is equivalent to that supporting the first pressing cylinder 41 in the first embodiment.

In the printing device 61 in which the first press cylinder 41 is provided in the paper discharge mechanism 18 in this way, the ink on the surface of the sheet 4 is pressed by the second press cylinder 48 during single-sided printing. The sheet 4 that has passed between the second press cylinder 48 and the first paper delivery side transfer cylinder 44 is transferred to the second paper delivery side transfer cylinder 46 and conveyed, and is then conveyed to the second paper delivery side transfer cylinder 46. It passes between the cylinder 46 and the first pressing cylinder 41. At this time, since no ink is attached to the back surface of the sheet 4, the sheet 4 is hardly pressed. Note that the bearing structure 42 that supports the first press cylinder 41 can be provided with a moving mechanism that retracts the first press cylinder 41 in a direction away from the sheet 4 during single-sided printing. By adopting this configuration, it is possible to avoid unnecessary contact of the first press cylinder 41 with the sheet 4 during single-sided printing.

On the other hand, during double-sided printing, the second press cylinder 48 presses the ink on the back side of the sheet 4, and the first press cylinder 41 presses the ink on the front side of the sheet 4. Therefore, even when this embodiment is adopted, the ink film thickness is reduced and the ink surface is flat in both single-sided printing and double-sided printing, as in the case of the first embodiment. This makes it possible to give the printed area a glossy appearance.

In the printing device 61 according to this embodiment, the first press cylinder 41 and the second press cylinder 48 are provided in the paper discharge mechanism 18. Therefore, a strong support structure for supporting the first press cylinder 41 and the second press cylinder 48 can be assembled in the paper discharge mechanism 18, so that highly rigid parts can be distributed in multiple locations. The manufacturing of the printing device becomes easier than in the case of the conventional method.

The printing apparatuses 1 and 61 shown in the first embodiment and the second embodiment described above are both equipped with a reversing mechanism 17 that uses a reversing swing device 37 (reversing means). Therefore, the reversing mechanism 17 can be realized compactly, and it is possible to provide a printing device that is compact despite being provided with the first and second press cylinders 41 and 48 and is capable of double-sided printing. can.

The printing apparatuses 1 and 61 shown in the first embodiment and the second embodiment described above each have first and second paper discharge side transfer cylinders 44, 46 and a second paper discharge side transfer cylinder. It includes a discharge belt 47 (discharge means) that receives and discharges the sheet 4 from the cylinder 46. Therefore, it becomes possible to use the first and second paper delivery side transfer cylinders 44 and 46 as cylinders for receiving the pressing force of the first pressing cylinder 41 and the second pressing cylinder 48. 1. The degree of freedom is increased in setting the location of the second press cylinders 41, 48.

(Third embodiment)
The reversing mechanism can be configured as shown in FIG. In FIG. 7, the same or equivalent members as those explained with reference to FIGS. 1 to 4 are given the same reference numerals, and detailed explanations are omitted as appropriate.
The reversing mechanism 17 shown in FIG. 7 includes a reversing cylinder 71 between the pre-reversing doubling cylinder 35 and the supply cylinder 15, and does not include the reversing swing device 37 described above. Note that the configuration of this embodiment other than the reversing mechanism 17 may be the same as that of the first embodiment, although some of the configuration is shown in the drawings.

The reversing cylinder 71 rotates in synchronization with each cylinder that conveys the sheet 4, receives the sheet 4 from the pre-reversing doubling cylinder 35, reverses the front and back of the sheet 4, and transfers the reversed sheet 4 to the supply cylinder 15. supply The supply cylinder 15 shown in FIG. 7 is constituted by a double cylinder.
The reversing drum 71 is equivalent to the reversing drum disclosed in, for example, Japanese Patent Application Laid-Open No. 5-16330, and is located at the upstream end in the conveying direction of the sheet 4 being conveyed by the pre-reversing doubling cylinder 35. It has a grip member 72 that grips the end 4b.

By rotating the reversing cylinder 71 with the grip member 72 gripping the rear end of the sheet 4, the sheet 4 is transported toward the supply cylinder 15 with the rear end 4b of the sheet 4 located on the downstream side in the transport direction. be done. The sheet 4 thus conveyed is transferred from the grip member 72 to the gripper device 21 of the supply cylinder 15 . When the sheet 4 is conveyed by the supply cylinder 15, the surface of the sheet 4 is exposed outside the supply cylinder 15. Therefore, the sheet 4 conveyed through the reversing mechanism 17 is conveyed from the supply cylinder 15 to the printing cylinder 16 with the front and back sides reversed.

Even if the reversing mechanism 17 is configured as shown in FIG. 7, the ink film thickness will be small and the ink surface will be flat in both single-sided printing and double-sided printing, as in the first embodiment. This makes it possible to give the printed area a glossy appearance.

In the first to third embodiments described above, an example was shown in which the pressing means according to the present invention is constituted by the first pressing cylinder 41 and the second pressing cylinder 48. However, the pressing means is not limited to such a limitation, and can be composed of one or more rollers.

(Fourth embodiment)
In each of the embodiments described above, an example is shown in which the present invention is applied to a printing device that can print on both the front and back sides of a sheet, but the present invention can also be applied to a printing device that prints only on one side of a sheet. can do. An example of a printing device adopting this configuration is shown in FIG. In FIG. 8, the same or equivalent members as those explained with reference to FIGS. 1 to 4 are given the same reference numerals, and detailed explanations are omitted as appropriate.

A printing device 81 shown in FIG. 8 has a configuration in which the reversing mechanism 17 is removed from the printing device 1 shown in the first embodiment. Therefore, the discharge cylinder 5 provided in this printing device 81 is not equipped with a switching mechanism for switching the conveyance destination of the sheet 4.
In the printing device 81 according to this embodiment, printing is performed on only one side of the sheet 4, and the printed sheet 4 is all sent from the discharge cylinder 5 to the first paper discharge side transfer cylinder 44. The sheet 4 is pressed by the second pressing cylinder 48 while being conveyed by the first paper delivery side transfer cylinder 44 . Therefore, in the printing device 81 configured to perform only one-sided printing, the film thickness of the ink after printing can be reduced, and a glossy appearance can be imparted to the printed portion on the surface of the sheet 4.

(Fifth embodiment)
The processing device according to the present invention can be applied to an offset printing device as shown in FIG. In FIG. 9, the same or equivalent members as those explained with reference to FIGS. 1 to 4 are given the same reference numerals, and detailed explanations are omitted as appropriate.
The printing unit 3 of the offset printing apparatus 91 shown in FIG. 9 removes the reversing mechanism 17 from the printing apparatus 1 shown in the first embodiment, and performs offset printing instead of the first to fourth inkjet heads 22 to 25. A configuration in which a portion 92 is provided is adopted. Therefore, the discharge cylinder 5 provided in this printing device 91 is not equipped with a switching mechanism for switching the conveyance destination of the sheet 4.

The offset printing unit 92 includes an ink supply device 94 that supplies ink to a plate cylinder 93, and a rubber unit that is supplied with ink from the plate cylinder 93 and that sandwiches the sheet 4 between the print cylinder 16 and transfers the ink to the sheet 4. It is equipped with a trunk 95 and the like.
In the printing device 91 according to this embodiment, printing is performed on only one side of the sheet 4 by offset printing, and the sheet 4 after printing passes near the ink drying means 27 and is discharged with the ink dried. The paper is sent from the cylinder 5 to the first paper delivery side transfer cylinder 44 . The sheet 4 is pressed by the second pressing cylinder 48 while being conveyed by the first paper delivery side transfer cylinder 44 . Therefore, in the printing device 91 configured to perform single-sided printing by offset printing, the film thickness of the ink after printing can be reduced, and a glossy appearance can be imparted to the printed portion on the surface of the sheet 4.

(Sixth embodiment)
The processing apparatus according to the present invention can be applied to a coating apparatus as shown in FIG. In FIG. 10, members that are the same or equivalent to those described with reference to FIGS. 1 to 4 are designated by the same reference numerals, and detailed descriptions thereof will be omitted as appropriate.
A coating apparatus 101 shown in FIG. 10 has a configuration in which the reversing mechanism 17 is removed from the printing apparatus 1 shown in the first embodiment, and a coating section 102 is provided in place of the first to fourth inkjet heads 22 to 25. is taken. Therefore, the discharge cylinder 5 provided in this coating apparatus 101 is not equipped with a switching mechanism for switching the conveyance destination of the sheet 4.

The coating section 102 includes a coater cylinder 103 that faces the printing cylinder 16 and a varnish supply cylinder 104 that supplies varnish to the coater cylinder 103.
In this coating device 101 , when the sheet 4 being conveyed by the printing cylinder 16 passes between the coater cylinder 103 and the printing cylinder 16 , varnish is transferred from the coater cylinder 103 to the surface of the sheet 4 . is coated with varnish. The coated sheet 4 passes near the ink drying means 27 and is then sent from the discharge cylinder 5 to the first paper transfer cylinder 44 in a state in which the varnish is dried. The sheet 4 is pressed by the second pressing cylinder 48 while being conveyed by the first paper delivery side transfer cylinder 44 . Therefore, in the coating apparatus 101 that performs varnish coating, the thickness of the varnish after coating can be reduced, and a glossy appearance can be imparted to the coated portion of the surface of the sheet 4.

(Other examples of adjusting the pressing force)
In each of the embodiments described above, the pressing force when the first and second pressing cylinders 41 and 48 press the sheet 4 is different from that of the first and second pressing cylinders 41 and 48 and the reversing side transfer cylinder 33, An example is shown in which the distance between the axes of the first paper discharge side transfer cylinder 44, the second paper discharge side transfer cylinder 46, etc. is changed and adjusted. This pressing force can be automatically adjusted by changing the above-mentioned distance between the axes using an actuator (not shown). In this case, the operation of the actuator is controlled depending on the thickness of the printing base material (paper, etc.) constituting the sheet 4 and the density of the printed pattern. The operation of the actuator can be controlled by a control device, and can be automatically controlled based on the thickness of the printing substrate and pattern information input at the time of printing settings. For example, when the printing substrate is thick, or when the pattern is dark and the ink film is thick, the pressing force can be increased by operating the actuator so that the above-mentioned distance between the axes is shortened. I can do it.

DESCRIPTION OF SYMBOLS 1, 61, 81... Printing device, 4... Sheet, 5... Discharge cylinder (conveyance path switching means), 13... Control device, 16... Print cylinder (conveyance device), 17... Reversing mechanism, 18... Paper discharge mechanism, 22 ...First inkjet head (printing head), 23... Second inkjet head (printing head), 24... Third inkjet head (printing head), 25... Fourth inkjet head (printing head), 27... Ink Drying means (ink drying device), 33... Reversing side transfer cylinder, 35... Pre-reversing doubling cylinder (pre-reversing cylinder), 37... Reversing swing device (reversing means), 41... First pressing cylinder (first pressing means) ), 44...First paper delivery side transfer cylinder, 46...Second paper delivery side transfer cylinder, 47...Discharge belt (sheet discharge means), 48...Second press cylinder (second press means), 71 ...Reversing cylinder (reversing means), 91... Offset printing device, 101... Coating device.

Claims (9)

a conveyance device that holds and conveys the sheet;
a processing device main body that performs processing on the processing surface of the sheet held by the conveying device;
A processing apparatus characterized by comprising: a pressing means that is provided on the downstream side of the processing apparatus main body in a sheet conveyance direction and presses a processing surface of the sheet. The processing device according to claim 1,
The processing device main body includes a plurality of print heads that eject ink onto the processing surface of the sheet held by the transport device;
A processing device comprising: an ink drying device that is provided downstream of the print head in a sheet conveying direction and dries the ink attached to the sheet. The processing device according to claim 2,
It is configured to be able to perform double-sided printing in which both the front and back sides of the sheet are the printing surfaces, and single-sided printing in which one side of the sheet is the printing surface,
The pressing means is
a first pressing means for pressing one printing surface of the sheet during double-sided printing;
A processing device comprising a second pressing means that presses the other printing surface of the sheet during double-sided printing and presses the printing surface of the sheet during single-sided printing. The processing device according to claim 3,
moreover,
a control device capable of switching to either one-sided printing or double-sided printing;
a conveyance path switching means located downstream of the ink drying device in the sheet conveyance direction and configured to switch the conveyance destination of the sheet according to the print mode of the control device;
The conveyance destination of the sheet by the conveyance path switching means is as follows:
a reversing mechanism for reversing the front and back of the sheet and returning it to the conveying device when the print mode of the control device is a double-sided printing mode and printing has been completed on only one side of the sheet;
1. A processing device comprising: a paper ejecting mechanism that ejects a sheet when the printing mode is one-sided printing, or when printing has been completed on both sides of the sheet in the printing mode two-sided printing. The processing device according to claim 4,
the first pressing means is provided in the reversing mechanism,
A processing device characterized in that the second pressing means is included in the paper ejecting mechanism. The processing device according to claim 4,
A processing apparatus characterized in that the first pressing means and the second pressing means are provided in the paper ejecting mechanism. The processing device according to claim 5 or 6,
The reversing mechanism is
a reversing side transfer drum that receives sheets from the conveyance path switching means;
a reversing front trunk that receives sheets from the reversing side transfer trunk;
A processing device comprising: a reversing unit that grips the trailing edge of the sheet conveyed to the front reversing cylinder and returns the sheet to the conveying device. The processing device according to claim 7,
The paper ejection mechanism is
a first paper delivery side transfer cylinder that receives the sheet from the transport path switching means;
a second paper delivery side transfer cylinder that receives the sheet from the first paper delivery side transfer cylinder;
A processing device comprising: a sheet discharging means for receiving a sheet from the second sheet discharging side transfer cylinder and discharging the sheet. The processing device according to claim 5 or 6,
The paper ejection mechanism is
a first paper delivery side transfer cylinder that receives the sheet from the transport path switching means;
a second paper delivery side transfer cylinder that receives the sheet from the first paper delivery side transfer cylinder;
A processing device comprising: a sheet discharging means for receiving a sheet from the second sheet discharging side transfer cylinder and discharging the sheet.

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