Printing device

Abstract

A printing apparatus (1) is provided with a processing cylinder (17) configured to transport a sheet (4), a processing device (23) that performs printing on the sheet (4) on the processing cylinder (17), a supply cylinder (16) that supplies the sheet (4) to the processing cylinder (17), a transport mechanism (18) that receives the sheet (4) from the processing cylinder (17) and sends the sheet (4) to a device in the next step, and a turn-over cylinder (51) that turns over the front and back of the sheet (4) from the transport mechanism (18) and supplies the sheet (4) to the supply cylinder (16). According to this configuration, the sheet can be easily turned over at high speed, and printing failure can be prevented at the time of turning over.

Description

Technical Field

[0001] The present invention relates to a printing apparatus, comprising: a processing cylinder that holds and conveys a sheet; and a processing device for performing a process including printing on the sheet on the processing cylinder. Background Technology

[0002] Patent Document 1 discloses an example of a conventional printing apparatus including an inkjet head. The printing apparatus disclosed in Patent Document 1 includes a flipping oscillating device for flipping the front and back sides of a printed sheet and returning it to the printing cylinder, thereby enabling printing on both sides of the sheet using the inkjet head. The flipping oscillating device is configured to oscillate towards the printing cylinder while gripping the upstream edge of the sheet in the sheet transport direction, and to transfer the sheet to a gripper mechanism of the printing cylinder.

[0003] Because the tumbling and oscillating device flips the sheet through reciprocating motion, acceleration and deceleration of the device itself are necessary. This results in a significant load on the equipment and limitations on increasing speed. Furthermore, when the sheet is flipped by the tumbling and oscillating device, there is a problem of the sheet's tail edge (paper tail) floating in the air. This can lead to printing defects, such as the tail edge (paper tail) swinging excessively and damaging the sheet, friction between the sheet and surrounding components, or wrinkles forming within the sheet.

[0004] List of cited references

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent No. 2017-210337

[0007] Patent Document 2: Japanese Patent No. 2013-240987

[0008] Patent Document 3: Japanese Patent No. H05-16330 Summary of the Invention

[0009] Technical issues

[0010] The purpose of this invention is to provide a printing apparatus that can easily increase the speed of sheet flipping without causing printing defects during the flipping process.

[0011] Solution

[0012] One aspect of the present invention relates to a printing apparatus, comprising: a processing roller configured to convey a sheet; a processing device configured to perform a processing including printing on the sheet on the processing roller; a supply roller configured to supply the sheet to the processing roller; a conveying mechanism configured to receive the processed sheet from the processing roller and convey the sheet to a device for the next processing; and a flipping roller configured to receive the sheet from the conveying mechanism, flip the front and back sides of the sheet, and supply the flipped sheet to the supply roller. The flipping roller may contact the supply roller.

[0013] The tilting roller may include a gripping member configured to grip the trailing edge of a sheet on its upstream side along the sheet conveying direction. The gripping member may be configured to pivot relative to the tilting roller about an axis parallel to the axis of the tilting roller. The gripping member may include jaws and jaw pads. The jaws may be configured to swing between a closed position and an open position, in which the sheet is gripped between the jaws and the jaw pads, and in the open position, the jaws are separated from the jaw pads. The gripping member of the tilting roller can convey the sheet to the gripping member of the supply roller.

[0014] The conveying mechanism may include an adsorption roller configured to adsorb the tail edge of a sheet located upstream in the sheet conveying direction. The tilting roller may include a gripping member configured to grip the sheet adsorbed onto the tail edge of the adsorption roller. The gripping member may be configured to pivot relative to the tilting roller about an axis parallel to the axis of the tilting roller. The gripping member may include jaws and jaw pads. The jaws may be configured to swing between a closed position and an open position, in which the sheet is gripped between the jaws and the jaw pads, and in the open position, the jaws are separated from the jaw pads. The gripping member of the tilting roller may convey the sheet to the gripping member of the supply roller.

[0015] The tumbling roller may further include an adsorption member configured to adsorb the tail edge of a sheet onto the roller and convey it to a gripping member. The adsorption member may include an adsorption surface having adsorption holes for adsorbing the tail edge of the sheet. The tail edge of the sheet is adsorbed onto the adsorption surface. The adsorption member may include a base end supported on the tumbling roller to allow it to oscillate about an axis parallel to the axis of the tumbling roller. By oscillating, the adsorption member can be positioned either radially outward from the adsorption roller or oriented towards the gripping member.

[0016] The printing apparatus may also include a delivery unit configured to stack sheets from a conveying mechanism. The conveying mechanism may include a sheet path distribution device configured to guide the sheets along a flipping path including a path on a flipping roller or along a discharge path for conveying the sheets to the delivery unit.

[0017] When the conveying mechanism includes an adsorption roller, the adsorption roller can be configured to guide the sheet along a flipping path including a path on a flipping roller or along a discharge path for conveying the sheet to a delivery unit.

[0018] The printing apparatus may also include a sheet pressing roller configured to contact a supply roller and rotate while pressing the sheet onto the supply roller. A flipping roller may be configured to supply flipped sheet onto the supply roller at a position upstream of the position where the sheet is pressed by the sheet pressing roller in the sheet conveying direction.

[0019] The printing apparatus may also include a oscillating device configured to supply sheet to a feed roller. A flipping roller may be configured to supply flipped sheet to a position on the feed roller downstream of the position where the sheet is conveyed by the oscillating device in the sheet transport direction.

[0020] The printing apparatus may also include a heater for heating the outer periphery of the supply roller.

[0021] Beneficial effects of the present invention

[0022] The flipping roller for turning the front and back sides of a sheet can rotate continuously at a constant speed. Compared to conventional flipping oscillating devices that convey material while accelerating and decelerating, conveying the sheet through this flipping roller results in less swaying of the sheet's trailing edge. Therefore, according to one aspect of the invention, a printing apparatus can be provided that can easily increase the speed of sheet flipping without causing printing defects during the flipping process. Attached Figure Description

[0023] Figure 1 A side view of the construction of a printing apparatus according to a first embodiment is shown.

[0024] Figure 2 It shows Figure 1 A side view of the main part of the printing apparatus shown.

[0025] Figures 3A to 3C A schematic diagram illustrating the operation of the rotating drum is shown.

[0026] Figure 4 A side view of the construction of a printing apparatus according to a second embodiment is shown.

[0027] Figures 5A to 5C A schematic diagram illustrating the operation of the rotating drum is shown. Detailed Implementation

[0028] First Embodiment

[0029] The following will refer to Figure 1 , Figure 2 as well as Figures 3A to 3C A printing apparatus according to a first embodiment of the present invention is described.

[0030] Conveying device 1 transports sheet 4 from the location located Figure 1 The rightmost supply unit 2 delivers the material to the printing unit 3, where one or both sides of the sheet 4 are printed. The printed sheet 4 in the printing unit 3 is then sent to the delivery unit 5 and stacked in the delivery stack 6.

[0031] The supply unit 2 has a structure that transfers sheet 4 from supply stack 11 to supply plate 13 via a suction nozzle 12. The suction nozzle 12 is connected to an intermittent supply valve 14 and operates in either a continuous sheet feeding mode or an intermittent sheet feeding mode. When printing is performed only on the front side of sheet 4, the suction nozzle 12 continuously feeds sheet 4 to supply plate 13. Simultaneously, when printing is performed on both the front and back sides of sheet 4, the suction nozzle 12 intermittently feeds sheet 4 to supply plate 13.

[0032] The printing unit 3 includes: a supply roller 16, to which sheet 4 from supply unit 2 is supplied via a swing device 15; a processing roller 17, to which sheet 4 is sent from supply roller 16; and a conveying mechanism 18 to which printed sheet 4 is sent.

[0033] The supply roller 16 is a double-diameter roller with twice the diameter of a single roller, and as... Figure 2 As shown, the supply roller 16 has two transport surfaces 16a that hold the sheet 4 at two locations in the rotational direction. These two transport surfaces 16a are formed by the outer peripheral surface of the supply roller 16, and the outer peripheral surface is bisected in the rotational direction when viewed from the axial direction of the supply roller 16. An outer peripheral cutout 16b is provided between adjacent transport surfaces 16a. A gripper device 44 is provided in the outer peripheral cutout 16b. The gripper device 44 grips and holds the leading edge 4a, which is the end of the sheet 4 on the downstream side in the sheet transport direction, and supplies the sheet 4 received from the swing device 15 to the processing roller 17 at the supply position P1.

[0034] A heater 21 for heating the outer periphery of the supply roller 16 is provided near the supply roller 16. By heating the supply roller 16 with the heater 21, the heat of the supply roller 16 is transferred to the sheet 4 during the conveying of the sheet 4 by the supply roller 16, thereby raising the temperature of the sheet 4.

[0035] Furthermore, between position P4, where the sheet 4 is supplied by the oscillating device 15, and position P1, the sheet pressing roller 22 contacts the outer peripheral surface of the supply roller 16. The sheet pressing roller 22 rotates while pressing the sheet 4, conveyed by the supply roller 16, onto the supply roller 16. By pressing the sheet 4 onto the supply roller 16 in this manner with the sheet pressing roller 22, the heat from the supply roller 16 is efficiently transferred to the sheet 4, and the temperature of the sheet 4 can be reliably raised to the target temperature.

[0036] The processing roller 17 picks up the sheet 4 and conveys it to a position where it is processed by the processing apparatus 23, which will be described later. According to this embodiment, the processing roller 17 is a three-diameter roller, three times the diameter of a single roller, and as... Figure 2 As shown, the processing roller 17 has three transport surfaces 17a that hold the sheet 4 at three locations in the rotational direction. These three transport surfaces 17a are formed by the outer peripheral surface of the processing roller 17, and the outer peripheral surface is divided into three equal parts in the rotational direction when viewed from the axial direction of the processing roller 17. A peripheral cutout 24 is provided between adjacent transport surfaces 17a. A gripper device 25 is provided in the peripheral cutout 24. The gripper device 25 grips and holds the leading edge 4a, which is the downstream end of the sheet 4 in the sheet transport direction.

[0037] Downstream of the feed roller 16 along the sheet conveying direction, near the circumference of the processing roller 17, a pre-printing treatment device 31, a first inkjet head 26, a second inkjet head 27, a third inkjet head 28, and a fourth inkjet head 29, as well as an ink drying lamp 30, are arranged sequentially along the sheet conveying direction. The pre-printing treatment device 31 is, for example, a pre-coating device for applying a pre-coating layer to the sheet 4 before printing, or a corona treatment device for corona discharge treatment of the sheet 4 before printing.

[0038] The first to fourth inkjet heads 26 to 29 perform printing by ejecting ink droplets onto the sheet 4. Each of the first to fourth inkjet heads 26 to 29 is provided with a plurality of nozzles (not shown) along the axial direction of the processing roller 17. Figure 2 The inkjet heads 26 to 29 are arranged perpendicular to the paper surface. Each of the first to fourth inkjet heads 26 to 29 is provided with a heater (not shown) for heating the ink to a predetermined temperature so that the ink droplets adhere properly to the sheet 4.

[0039] The ink drying lamp 30 is used to cure the ink applied to the sheet 4 by the first to fourth inkjet heads 26 to 29. The ink drying lamp 30 irradiates the sheet 4 with infrared or ultraviolet light. The ink is dried or cured by being irradiated with infrared or ultraviolet light.

[0040] In this embodiment, the pre-printing processing device 31, the first to fourth inkjet heads 26 to 29, and the ink drying lamp 30 constitute the processing device 23, used to perform processing, including printing, on the sheet 4 on the processing roller 17. It should be noted that the pre-printing processing device 31 and the ink drying lamp 30 are not essential.

[0041] The conveying mechanism 18 is configured using multiple conveying rollers and receives the printed sheet 4 at a receiving position P2 downstream of the first to fourth inkjet heads 26 to 29 in the sheet conveying direction. The multiple conveying rollers include: an exhaust roller 41 for receiving the sheet 4 from the processing roller 17 at the receiving position P2; an exhaust-side transfer roller 42 for receiving the sheet 4 from the exhaust roller 41; and a double-diameter roller 43 before flipping for receiving the sheet 4 from the exhaust-side transfer roller 42.

[0042] The feed roller 16, discharge roller 41, discharge-side conveyor roller 42, and double-diameter roller 43 before tilting are respectively equipped with gripper devices 44, 45, 46, and 47 to convey the sheet 4. These gripper devices 44 to 47 are equivalent to the gripper device 25 of the processing roller 17.

[0043] Among the sheets 4 received by the discharge roller 41 at the receiving position P2, the sheets 4 to be printed on the back side are returned to the supply roller 16 in a state where both the front and back sides are flipped through the flipping path 52 formed by the discharge side conveyor roller 42, the double diameter roller 43 before flipping, and the flipping roller 51 described later. At the same time, the sheets 4 with only the front side printed or the sheets 4 with both the front and back sides printed are discharged from the discharge roller 41 to the delivery unit 5 through the discharge path 54 including the conveyor belt 53.

[0044] In this embodiment, the discharge roller 41 constitutes a sheet path distribution device that distributes the conveying path to the flipping path 52 of the front and back sides of the flipped sheet 4 or the discharge path 54 of the discharged sheet 4. This sheet path distribution device can be configured using, for example, the technology disclosed in Patent Document 2. Patent Document 2 discloses a cam device that uses a cam to open and close the gripper device 45 of the discharge roller 41 to change the opening and closing timing of the gripper device 45 (the conveying timing of the sheet 4). This cam device is configured to convey the sheet 4 from the discharge roller 41 to the gripper device 46 of the discharge-side conveyor roller 42 or a gripper device (not shown) that moves with the conveyor belt 53.

[0045] The delivery unit 5 has three functions. The first function is to stack the printed sheets 4, which have been printed by the conveying mechanism 18, into the delivery stack 6. The second function is to extract samples. The third function is to transport the sheets 4 to the next process.

[0046] The flipping roller 51 rotates synchronously with the rollers 41 to 43 constituting the conveying mechanism 18, receives the sheet 4 from the conveying mechanism 18, flips the front and back sides of the sheet 4, and supplies the flipped sheet 4 to the supply roller 16. In this embodiment, the flipping roller 51 is, for example, equivalent to the steering roller disclosed in Patent Document 3, and as... Figures 3A-3C As shown, a gripping member 55 is included, which grips the trailing edge 4b ​​of the sheet 4, which is conveyed by the double-diameter roller 43 before tilting and located upstream in the sheet conveying direction. The gripping member 55 is pivotable relative to the tilting roller 51 about an axis parallel to the axis of the tilting roller 51.

[0047] Reference Figures 3A-3C Describes the flipping of sheet 4. Sheet 4 is conveyed by the double-diameter roller 43 before flipping, with the printed front side 4c in contact with the double-diameter roller 43 before flipping. For example... Figure 3A As shown, when the trailing edge 4b ​​of the sheet 4 passes between the double-diameter roller 43 and the flipping roller 51, the gripping member 55 of the flipping roller 51 grips and holds the trailing edge 4b ​​of the sheet 4. In this state, as the flipping roller 51 rotates, as... Figures 3B-3C As shown, sheet 4 is conveyed towards the feed roller 16 with its trailing edge 4b ​​located downstream along the sheet conveying direction. Sheet 4, conveyed in this manner via the flipping path 52, ... Figure 1 and Figure 2 The sheet 4 is conveyed to the supply roller 16 at the conveying position P3 shown. When the sheet 4 is conveyed by the supply roller 16, the front side 4c of the sheet 4 is exposed to the outside of the supply roller 16. Therefore, the sheet 4 conveyed by the flipping path 52 is conveyed from the supply roller 16 to the processing roller 17 with its front and back sides flipped.

[0048] The conveying position P3 is located downstream of the receiving position P4 where the supply roller 16 receives the sheet 4 from the oscillating device 15 in the sheet conveying direction, and upstream of the pressing position P5 where the sheet 4 is pressed by the sheet pressing roller 22 in the sheet conveying direction. That is, the flipping roller 51 is configured to supply the flipped sheet 4 at a position on the supply roller 16 that is downstream of the receiving position P4 and upstream of the pressing position P5. Therefore, the flipped sheet 4 is also pressed by the sheet pressing roller 22 before being conveyed to the processing roller 17.

[0049] As described above, the flipping roller 51 for flipping the sheet 4 can rotate continuously at a constant speed. Compared with conventional flipping oscillating devices that convey the sheet while accelerating and decelerating, the tail edge (paper tail) of the sheet 4 is less likely to oscillate when the flipping roller 51 conveys the sheet 4. Therefore, according to this embodiment, a printing apparatus can be provided that can easily increase the speed of flipping the sheet 4 without causing printing defects during the flipping process.

[0050] In this embodiment, the tilting roller 51 has a gripping member 55 that grips the trailing edge 4b ​​of the sheet 4 located upstream in the sheet conveying direction. The gripping member 55 is configured to pivot relative to the tilting roller 51 about an axis parallel to the axis of the tilting roller 51. Therefore, the sheet 4 conveyed by the tilting roller 51 follows the outer peripheral surface of the tilting roller 51, thereby facilitating the stabilization of the sheet 4's posture during conveying.

[0051] Second Embodiment

[0052] Next, refer to Figure 4 and Figures 5A to 5C A printing apparatus according to a second embodiment of the present invention is described. In these figures, [the following text is incomplete and likely refers to a different document or diagram]. Figures 1 to 3C Elements that are the same or equivalent as those shown are indicated by the same reference numerals, and their detailed descriptions are omitted where appropriate.

[0053] Figure 4 The printing apparatus 61 shown is Figure 1 The printing apparatus 1 shown differs in that: the supply roller 16 is a single roller; the conveying mechanism 18 for receiving the sheet 4 from the processing roller 17 consists of a suction roller 62; and a suction-type flipping roller 63 is used. Other constructions are similar to... Figure 1 The printing apparatus 1 shown is equivalent to that shown.

[0054] The adsorption roller 62 conveys the sheet 4 in the following manner: it holds the leading edge 4a of the end of the sheet 4 located on the downstream side along the sheet conveying direction, while adsorbing the trailing edge 4b ​​of the end of the sheet 4 located on the upstream side (i.e., the adsorption roller 62 is a double-diameter roller and has conveying surfaces 62a that hold the sheet 4 at two locations in the rotational direction. These two conveying surfaces 62a are formed by the outer peripheral surface of the adsorption roller 62, and the outer peripheral surface is bisected in the rotational direction when viewed from the axial direction of the adsorption roller 62. An outer peripheral cutout 62b is provided between adjacent conveying surfaces 62a.

[0055] A gripper device 64 is provided upstream in the outer peripheral cut portion 62b along the sheet conveying direction. The gripper device 64 is equivalent to the gripper device 25 of the processing roller 17, and grips and holds the leading edge 4a of the sheet 4. An adsorption device 65 is provided downstream in the outer peripheral cut portion 62b along the sheet conveying direction. The adsorption device 65 adsorbs the trailing edge 4b ​​of the sheet 4 by the action of negative pressure from a negative pressure source, so that the trailing edge portion of the sheet 4 is tightly attached to the outer peripheral surface of the adsorption roller 62.

[0056] The flipping roller 63 receives the sheet 4 from the adsorption roller 62, flips the front and back sides of the sheet 4, and sends it to the supply roller 16. The flipping roller 63 is a single roller and, as shown in FIG. 5, has a notch 66 with an opening on its outer peripheral surface. An adsorption member 67 is provided in the notch 66 on the downstream side along the sheet conveying direction, and a gripper device 68 (gripping member) for gripping the sheet 4 is provided in the notch 66 on the upstream side along the sheet conveying direction.

[0057] The end of the adsorption member 67 includes an adsorption surface 67a having a plurality of adsorption holes for adsorbing the sheet 4, and the sheet 4 is adsorbed onto the adsorption surface 67a. The base end 67b of the adsorption member 67 is supported by the tilting roller 63 in a manner that allows it to swing about an axis parallel to the axis of the tilting roller 63. By swinging the adsorption member 67, the adsorption member 67 can be positioned outward of the adsorption surface 67a in the radial direction toward the adsorption roller 62. Figure 5A and the state of the adsorption surface 67a facing the gripper device 68 (upstream side). Figure 5B ).

[0058] The gripper device 68 has grippers 68a and gripper pads 68b. Grippers 68a are supported in a swingable manner between a closed position and an open position. In the closed position, the sheet 4 is held between grippers 68a and gripper pads 68b; in the open position, grippers 68a and gripper pads 68b are separated. The gripper device 68 is supported by the tilting roller 63 in a swingable manner about an axis parallel to the axis of the tilting roller 63. By swinging the gripper device 68, the gripper device 68 can be positioned so that the ends of grippers 68a and gripper pads 68b face the adsorption member 67 (downstream side). Figure 5B ) and the state in which the ends of the grippers 68a and gripper pads 68b face outwards in the radial direction of the adsorption roller 62. Figure 5C ).

[0059] In this embodiment, the printed sheet 4 is sent from the processing roller 17 to the adsorption roller 62. Among the sheets 4 received by the adsorption roller 62, those with the back side to be printed are returned to the supply roller 16 in a flipped state, with both the front and back sides flipped, via a flipping path 71 extending from the adsorption roller 62 to the flipping roller 63. Simultaneously, sheets 4 with only the front side 4c printed, or sheets 4 with both the front and back sides printed, are discharged from the adsorption roller 62 to the delivery unit 5 via a discharge path 73 including a conveyor belt 72 (see [link to relevant documentation]). Figure 4 In this embodiment, the adsorption roller 62 constitutes a sheet path distribution device, which distributes the conveying path to the flipping path 71 that flips the front and back sides of the sheet 4 or the discharge path 73 that discharges the sheet 4.

[0060] The sheet 4, conveyed from the processing roller 17 to the adsorption roller 62, is transported by the adsorption roller 62 with its leading edge 4a held by the gripper device 64 and its trailing edge 4b ​​adsorbed by the adsorption device 65. To flip the front and back sides of the sheet 4, firstly, as... Figure 5A As shown, the tail edge 4b ​​of the sheet 4 conveyed by the adsorption roller 62 is sucked onto the adsorption member 67 of the flipping roller 63.

[0061] More specifically, as the trailing edge 4b ​​of the sheet 4 is about to pass between the adsorption roller 62 and the rotating roller 63, the adsorption surface 67a of the rotating roller 63, facing outward in the radial direction of the adsorption roller 62, begins to adsorb the trailing edge 4b ​​of the sheet 4. The adsorption device 65 of the adsorption roller 62 stops adsorbing the trailing edge 4b ​​of the sheet 4, and the gripper device 64 of the adsorption roller 62 releases the leading edge 4a of the sheet 4. As a result, the trailing edge 4b ​​of the sheet 4 is transferred from the adsorption device 65 of the adsorption roller 62 to the adsorption member 67 of the rotating roller 63.

[0062] Subsequently, the adsorption member 67 of the adsorption surface 67a adsorbs the tail edge 4b ​​of the adsorption sheet 4, and the gripper device 68 of its end portion facing the radial direction outward towards the adsorption roller 62, both rotate toward the inside of the notch 66. Figure 5A (in the direction indicated by the middle arrow), and as Figure 5B As shown, the adsorption surface 67a of the adsorption member 67 is opposite to the ends of the gripper 68a and gripper pad 68b. At this time, as the gripper 68a approaches the gripper pad 68b, the gripper 68a and gripper pad 68b grasp and hold the trailing edge 4b ​​of the sheet 4. Simultaneously, the adsorption member 67 stops adsorbing the trailing edge 4b ​​of the sheet 4, thereby transferring the trailing edge 4b ​​of the sheet 4 from the adsorption member 67 to the gripper device 68.

[0063] The grippers 68a and gripper pads 68b holding the trailing edge 4b ​​of sheet 4 are aligned with the outside of the notch 66 as the rotating roller 63 rotates. Figure 5A Rotate in the opposite direction of the arrow shown. As a result, sheet 4 unfolds along the outer peripheral surface of the flipping roller 63.

[0064] like Figure 5C As shown, when the trailing edge 4b ​​of the sheet 4 is about to pass between the tilting roller 63 and the supply roller 16, the end of the gripper device 68 of the tilting roller 63 is guided outward in the radial direction of the tilting roller 63 and faces the gripper device 44 of the supply roller 16. The gripper 68a separates from the gripper pad 68b, and the trailing edge 4b ​​of the sheet 4 is transferred from the gripper device 68 of the tilting roller 63 to the gripper device 44 of the supply roller 16.

[0065] When sheet 4 is conveyed by the supply roller 16, the front side 4c of sheet 4 is exposed to the outside of the supply roller 16. Therefore, sheet 4, conveyed by the flipping path 71, is conveyed from the supply roller 16 to the processing roller 17 in a flipped state.

[0066] The flipping roller 63 can rotate continuously at a constant speed. Therefore, this embodiment can also provide a printing apparatus that can easily increase the speed of sheet flipping and does not cause printing defects during the flipping process.

[0067] In this embodiment, the conveying mechanism 18 is composed of an adsorption roller 62 that adsorbs the trailing edge 4b ​​of the sheet 4. The tilting roller 63 has a gripper device 68 (grasping member) that grips the trailing edge 4b ​​of the sheet 4 adsorbed by the adsorption roller 62. The gripper device 68 is configured to pivot relative to the tilting roller 63 about an axis parallel to the axis of the tilting roller 63. Therefore, the sheet 4 conveyed by the tilting roller 63 follows the outer peripheral surface of the tilting roller 63, thereby facilitating the stabilization of the sheet 4's posture during conveying.

[0068] The conveying mechanism 18 shown in the first and second embodiments includes a sheet path distribution device that distributes the conveying path to either a flipping path 71 including a flipping roller 63 or a discharge path 73 for conveying the sheet 4 to a delivery unit 5 for stacking the sheet 4. Therefore, it is easy to switch between an operation mode that prints only on one side of the sheet 4 and an operation mode that prints on both sides of the sheet 4. It should be noted that, in the second embodiment, as in the first embodiment, the discharge roller 41 and the discharge-side conveying roller 42, which serve as the sheet path distribution device, can also be provided separately from the adsorption roller 62.

[0069] In the first and second embodiments, the supply roller 16 contacts the sheet pressing roller 22, which rotates while pressing the sheet 4 onto the supply roller 16. Therefore, since the heat from the supply roller 16 in contact with the sheet 4 can be used to raise the temperature of the sheet 4 supplied to the processing roller 17 to a predetermined temperature, uneven temperature distribution of the sheet 4 is less likely to occur.

[0070] List of reference numerals

[0071] 1.61: Printing apparatus

[0072] 4: Sheets

[0073] 5: Delivery Unit

[0074] 16: Supply roller

[0075] 17: Handling the rollers

[0076] 18: Conveying mechanism

[0077] 22: Sheet pressing roller

[0078] 23: Processing device

[0079] 41: Discharge roller (sheet path distribution device)

[0080] 51, 63: Tilting rollers

[0081] 52, 71: Reverse path

[0082] 54, 73: Discharge Path

[0083] 55: Grasping Components

[0084] 62: Adsorption roller (sheet path distribution device)

[0085] 67: Adsorption component (gripping component)

[0086] 68: Tilting roller gripper device (gripping component)

Claims

1. A printing apparatus, comprising: A processing roller configured to convey sheets; A processing apparatus configured to perform a process including printing on a sheet on a processing roller; A supply roller configured to supply sheet material to a processing roller; A conveying mechanism configured to receive processed sheets from a processing drum and send the sheets to a device for further processing; as well as A flipping roller is configured to receive a sheet from a conveying mechanism, flip the front and back sides of the sheet, and supply the flipped sheet to a supply roller.

2. The printing apparatus according to claim 1, wherein, The tilting roller includes a gripping member configured to grip the tail edge of the sheet located on the upstream side along the sheet conveying direction; and The gripping member is configured to pivot relative to the tilting roller about an axis parallel to the axis of the tilting roller.

3. The printing apparatus according to claim 1, wherein, The conveying mechanism includes an adsorption roller, which is configured to adsorb the tail edge of the sheet located on the upstream side along the sheet conveying direction; The flipping roller includes a gripping member configured to grip the tail edge of the sheet that is adsorbed onto the adsorption roller. and The gripping member is configured to pivot relative to the tilting roller about an axis parallel to the axis of the tilting roller.

4. The printing apparatus according to claim 2 or 3, further comprising a delivery unit configured to stack sheets from the conveying mechanism, wherein, The conveying mechanism includes a sheet path distribution device configured to guide the sheet along a flipping path including a path on a flipping roller or along a discharge path for conveying the sheet to a delivery unit.

5. The printing apparatus of claim 3, further comprising a delivery unit configured to stack sheets from the conveying mechanism, wherein, The adsorption roller is configured to guide the sheet along a flipping path that includes a path on the flipping roller or along a discharge path for conveying the sheet to the delivery unit.

6. The printing apparatus of claim 1, further comprising a sheet pressing roller, the sheet pressing roller being configured to contact a supply roller and rotate while pressing the sheet onto the supply roller, wherein, The flipping roller is configured to supply the flipped sheet to the supply roller at a position upstream of the position where the sheet is pressed by the sheet pressing roller in the sheet conveying direction.

7. The printing apparatus according to claim 1 or 6, further comprising a oscillating device configured to feed sheet to a feed roller, wherein, The flipping roller is configured to supply the flipped sheet to a position on the supply roller downstream of the position where the sheet is conveyed by the oscillating device in the sheet conveying direction.

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