Sheet suction device, sheet transport device, printing device

Abstract

To achieve automation of switching of a suction region.SOLUTION: A sheet suction apparatus includes: a drum 51 that supports a sheet P on the peripheral surface and is rotated by drive means 501; a suction hole 112 provided in a plurality of support regions, supporting the sheet P of the drum 51; a suction apparatus 52 sucking through the sucking hole 112; and a rotary valve 200 provided between the plurality of suction holes 112 and the suction apparatus 52 and including a first member 203 changing the number of the suction hole 112 communicating with the suction apparatus 52, of the plurality of suction holes 112, by relatively rotating to the drum 51, and conducts relative rotation of the first member 203 and the drum 51 through the drive means 501.SELECTED DRAWING: Figure 19

Description

[Technical field]

[0001] The present invention relates to a sheet suction device, a sheet transport device, and a printing apparatus. [Background technology]

[0002] 2. Description of the Related Art Printing devices include those that carry and transport a sheet on a rotating member such as a drum and perform printing on the sheet.

[0003] 2. Description of the Related Art As a conveying device for conveying a sheet, a sheet conveying device that conveys a sheet by supporting the sheet on the peripheral surface of a drum through suction and adsorption is known.

[0004] For example, a device is known which comprises a carrier member which rotates while carrying a sheet on its peripheral surface, a number of suction holes provided in the carrier area which carries the sheet on the carrier member, a suction means which draws air through the suction holes, and a first member interposed between the number of suction holes which communicate with the suction means by rotating the first member, and which is manually rotated and positioned using an index plunger or the like to rotate the first member (Patent Document 1). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2020-019637 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, in the configuration disclosed in Patent Document 1, the rotation of the first member is performed manually, and therefore there is a problem in that the manual task of switching the suction area every time the sheet size is changed is cumbersome.

[0007] The present invention has been made in view of the above problems, and an object of the present invention is to make it possible to automate the switching of suction areas. [Means for solving the problem]

[0008] In order to solve the above problems, the sheet suction device according to the present invention is a carrier member that carries a sheet on its circumferential surface and is rotated by a driving means; a plurality of suction holes provided in a support area of ​​the support member that supports the sheet; A suction means for suctioning through the suction hole; a first member that is interposed between the plurality of suction holes and the suction means and that changes the number of the suction holes that communicate with the suction means among the plurality of suction holes by rotating the first member relative to the support member; and a restraining means for restraining rotation of the first member relative to the support member, The relative rotation of the first member and the supporting member is performed by the driving means. stomach, The restraining means is a holding means for holding a relative phase between the first member and the support member; and opening means for opening the retaining means to permit relative rotation of the first member and the carrier member. The composition was as follows.

[0009] According to the present invention, it becomes possible to automate the switching of the suction area. [Brief description of the drawings]

[0010] [Figure 1] 1 is a schematic explanatory diagram of a printing device according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a plan view illustrating a discharge unit of the printing apparatus. [Diagram 3] FIG. 1 is an explanatory diagram illustrating a schematic overall configuration of a sheet suction device according to a first embodiment of the present invention. [Figure 4] FIG. 4 is an explanatory diagram for explaining a drive system of the drum. [Diagram 5] FIG. [Figure 6]11 is a schematic side view illustrating the support area of ​​the drum, its divided areas, and a rotation angle acquisition unit; FIG. [Figure 7] 4 is an explanatory diagram for explaining the arrangement of suction ports in the circumferential direction of the drum and the sheet size. FIG. [Figure 8] FIG. 2 is an explanatory external perspective view of a rotary valve. [Figure 9] FIG. [Figure 10] FIG. [Figure 11] FIG. 4 is a side view illustrating a fixing portion constituting the rotary valve. [Figure 12] FIG. 4 is an explanatory side view of a second member constituting the rotary valve. [Figure 13] FIG. 2 is an explanatory side view of a first member constituting the rotary valve. [Figure 14] FIG. 4 is an explanatory side view of a third member constituting the rotary valve. [Figure 15] 11 is an explanatory diagram for explaining switching (size switching) of the suction area by relative rotation between the first member and the second member. FIG. [Figure 16] FIG. [Figure 17] 13 is an explanatory side view of a rotating portion of a rotary valve for explaining the switching operation of the suction area by the first member. FIG. [Figure 18] FIG. [Figure 19] FIG. 2 is an explanatory diagram illustrating a mechanism for automating a rotation operation of a first member in the first embodiment of the present invention. [Figure 20] FIG. [Figure 21] 11 is an explanatory diagram for explaining the operation of the rotation operation automation mechanism. FIG. [Figure 22] 11 is an explanatory diagram for explaining the operation of the rotation operation automation mechanism. FIG. [Diagram 23] 10 is an explanatory diagram illustrating a configuration for acquiring information on a relative phase (relative angle) between a first member and a drum. FIG. [Figure 24]FIG. 11 is a block diagram illustrating a sheet conveying device according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. First, a first embodiment of the present invention will be described with reference to Fig. 1 and Fig. 2. Fig. 1 is a schematic explanatory diagram of a printing device according to the embodiment, and Fig. 2 is a plan explanatory diagram of an example of a discharge unit of the printing device.

[0012] The printing device 1 includes an input section 10, a printing section 20, a drying section 30, and an output section 40. In the printing device 1, the printing section 20 applies liquid to the sheet P input from the input section 10 to perform a required printing, and the drying section 30 dries the liquid adhering to the sheet P, and then the sheet P is discharged to the output section 40.

[0013] The carry-in section 10 includes an input tray 11 on which a plurality of sheets P are stacked, a feeding device 12 that separates and sends out the sheets P one by one from the input tray 11, and a pair of registration rollers 13 that sends the sheets P to the printing section 20.

[0014] Any feeding device can be used as the feeding device 12, such as a device using rollers or a device using air suction. After the leading edge of the sheet P sent out from the input tray 11 by the feeding device 12 reaches the pair of registration rollers 13, the pair of registration rollers 13 is driven at a predetermined timing to send the sheet P to the printing unit 20.

[0015] The printing unit 20 includes a sheet transport device 21 that transports the sheet P. The sheet transport device 21 includes a drum 51 that is a support member (rotating member) that supports the sheet P on its circumferential surface and rotates while receiving power from a driving means 58 (see FIG. 4), and a suction device 52 that is a suction means that generates a suction force on the circumferential surface of the drum 51. The printing unit 20 also includes a liquid discharge unit 22 that discharges liquid toward the sheet P supported by the drum 51 of the sheet transport device 21.

[0016] The printing section 20 also includes a transfer cylinder 24 that receives the fed sheet P and transfers the sheet P between the drum 51 and the printing section 20, and a transfer cylinder 25 that transfers the sheet P transported by the drum 51 to the drying section 30.

[0017] The sheet P transported from the carry-in section 10 to the printing section 20 has its leading edge gripped by a gripping means (sheet gripper) provided on the transfer cylinder 24, and is transported as the transfer cylinder 24 rotates. The sheet P transported by the transfer cylinder 24 is delivered to the drum 51 at a position opposite the drum 51.

[0018] A gripping means (sheet gripper) is also provided on the surface of the drum 51, and the leading edge of the sheet P is gripped by the gripping means (sheet gripper). A plurality of suction holes are formed and dispersed on the surface of the drum 51. A suction device 52, which is a suction means, generates a suction airflow that flows inward from the required suction holes of the drum 51.

[0019] Then, the sheet P transferred from the transfer cylinder 24 to the drum 51 has its leading edge gripped by the sheet gripper 106, and is adsorbed and supported on the drum 51 by the suction airflow of the suction device 52, and is transported as the drum 51 rotates.

[0020] The liquid discharge section 22 includes discharge units 23 (23A to 23F) which are liquid discharge means. For example, the discharge unit 23A discharges cyan (C) liquid, the discharge unit 23B discharges magenta (M) liquid, the discharge unit 23C discharges yellow (Y) liquid, and the discharge unit 23D discharges black (K) liquid. The discharge units 23F, 23F are used to discharge any of YMCK, or special liquids such as white and gold (silver). Furthermore, a discharge unit that discharges a treatment liquid such as a surface coating liquid can also be provided.

[0021] The ejection unit 23 is, for example, a full-line type head in which a plurality of liquid ejection heads (hereinafter simply referred to as "heads") 125, each having a nozzle row 126 in which a plurality of nozzles are arranged, are arranged on a base member 127, as shown in FIG.

[0022] The discharge operation of each discharge unit 23 of the liquid discharge section 22 is controlled by a drive signal corresponding to the printing information. When the sheet P supported on the drum passes through an area facing the liquid discharge section 22, liquid of each color is discharged from the discharge unit 23, and an image corresponding to the printing information is printed.

[0023] The drying section 30 includes a drying mechanism section 31 for drying the liquid adhering to the sheet P in the printing section 20, and a suction transport mechanism section 32 for transporting the sheet P transported from the printing section 20 under suction (suction transport).

[0024] The sheet P conveyed from the printing unit 20 is received by the suction conveying mechanism 32, conveyed to pass through the drying mechanism 31, and then delivered to the discharge unit .

[0025] When passing through the drying mechanism 31, the liquid on the sheet P is subjected to a drying process. As a result, the liquid content such as water in the liquid evaporates, the colorant contained in the liquid is fixed on the sheet P, and curling of the sheet P is suppressed.

[0026] The discharge section 40 includes a discharge tray 41 on which a plurality of sheets P are stacked. The sheets P conveyed from the drying section 30 are sequentially stacked and held on the discharge tray 41.

[0027] In addition, in the printing device 1, for example, a pre-processing unit that performs pre-processing on the sheet P can be arranged upstream of the printing unit 20, and a post-processing unit that performs post-processing on the sheet P having liquid attached thereto can be arranged between the drying unit 30 and the discharge unit 40.

[0028] An example of the pre-treatment section is a section that performs a pre-coating process in which a treatment liquid that reacts with the liquid to suppress bleeding is applied to the sheet P. An example of the post-treatment section is a section that performs a sheet reversing and conveying process in which the sheet printed in the printing section 20 is reversed and sent back to the printing section 20 to print on both sides of the sheet P, and a process for binding multiple sheets.

[0029] Furthermore, although an example has been described in which a liquid ejection means is provided as the printing section, printing can also be performed by means other than liquid ejection.

[0030] Next, a sheet suction device according to a first embodiment of the present invention will be described with reference to Fig. 3 and Fig. 4. Fig. 3 is an explanatory diagram for explaining the overall schematic configuration of the sheet suction device, and Fig. 4 is an explanatory diagram for explaining the drive system of the drum.

[0031] The sheet suction device 50 includes a drum 51, a suction device 52 which is a suction means, and a rotary valve 200 which serves as a suction area switching device and is disposed between the drum 51 and the suction device 52. The suction device 52 and the rotary valve 200 are in communication with each other via a hose (tube) 55A, and the rotary valve 200 and the drum 51 are in communication with each other via a hose (tube) 55B.

[0032] The rotary valve 200 has a rotating part 202 and a fixed part 201. The rotating part 202 is a rotating member that rotates together with the drum 51. The fixed part 201 is a fixed member that is connected to the suction device 52 and does not rotate together with the drum 51. Both the rotating part 202 and the fixed part 201 are made of metal plates processed into a disk shape.

[0033] A fixed portion 201 of the rotary valve 200 is fixed to a frame 100 of the printing apparatus 1. The frame 100 supports the drum 51, the transfer cylinder 24, the discharge unit 23, and the like.

[0034] Furthermore, by switching between communication and non-communication between the suction hole 112 of the drum 51 and the suction device 52 depending on the relative phase difference between the rotating part 202 and the fixed part 201, the generation of negative pressure on the peripheral surface of the drum 51 can be controlled.

[0035] The drum 51 is rotated by the rotation of a driving means 58 being transmitted to a shaft portion 103 via a driving force transmitting means 59 such as a gear train. The driving means 58 is, for example, a driving motor, and is attached to a support member 100a fixed to a frame 100.

[0036] Next, drum 51 will be described with reference to Fig. 5 to Fig. 7. Fig. 5 is an exploded perspective explanatory diagram of the drum, Fig. 6 is a schematic side explanatory diagram for explaining the carrying area of ​​the drum and its divided areas as well as the rotation angle acquisition means, and Fig. 7 is an explanatory diagram for explaining the arrangement of suction ports in the circumferential direction of the drum and the sheet size.

[0037] The drum 51 is composed of a drum body 101 and a suction plate 102. Note that a sealant such as a rubber sheet may be interposed between the suction plate 102 and the drum body 101.

[0038] The drum 51 has three holding areas 105 (105A to 105C) and is capable of holding a plurality of sheets P in the circumferential direction. As shown in Fig. 4, each holding area 105 is composed of a suction plate 102 having a plurality of suction holes 112 and forming a chamber 113 to which each suction hole 112 communicates, and a drum main body 101 in which a groove-shaped suction port 111 communicating with the chamber 113 is formed. A sheet gripper 106 (shown in a simplified manner) is disposed at the tip of the holding area 105 in the drum rotation direction.

[0039] Sheet regions S1 to S9 corresponding to multiple (here, nine) sheet sizes are allocated to one carrying region 105, and twelve suction ports 111a, 111b (111b1 to 111b11) are arranged in the circumferential direction. Here, the suction ports 111a (111a1 to 111a9) on the leading side in the rotation direction are arranged in the axial direction so as to correspond to the respective sheet sizes S1 to S9.

[0040] For example, suction ports 111a1 and 111b1 are arranged corresponding to the seat area S1 and communicate with a chamber 113 to which the plurality of suction holes 112 face. Suction ports 111a2 and 111b2 are arranged corresponding to the seat area S2 and communicate with a chamber 113 to which the plurality of suction holes 112 face in an area other than the seat area S1. The same applies to the other seat areas S3 to S9.

[0041] Further, one carrying region 105 is divided in the circumferential direction (rotational direction) into a first region 116A, a second region 116B, a third region 116C, and a fourth region 116D from the leading side in the rotational direction.

[0042] As shown in FIG. 7, the first region 116A is assigned to the suction port 111a at the front in the drum rotation direction, the second region 116B is assigned to the suction ports 111b1 to 111b3, the third region 116C is assigned to the suction ports 111b4 to 111b8, and the fourth region 116D is assigned to the suction ports 111b9 to 111b11.

[0043] Therefore, by connecting hose 55B to each suction port 111 (111a, 111b) on drum 51 and switching between generating and not generating negative pressure for each suction port 111 (111a, 111b), the suction range (suction area) can be switched.

[0044] Next, the rotation angle acquisition means of the drum 51 will be described with reference to FIG.

[0045] The drum 51 and the rotating portion 202 of the rotary valve 200 which rotates with the drum 51 receive power from a driving means (drive source) to perform rotational motion.

[0046] An encoder wheel 53 that rotates in synchronization with the drum 51 is attached to a rotating shaft 51a of the drum 51. In addition, a filler 56 that rotates in synchronization with the drum 51 is attached to the drum 51.

[0047] An encoder sensor 54 that detects the amount of rotation of the encoder wheel 53 and a home position sensor 57 that detects the filler 56 are attached to the frame 100 of the printing device 1. The home position sensor 57 detects the home position in the rotation direction of the drum 51 by detecting the filler 56 only once per pulse (once) per rotation of the drum. The encoder sensor 54 also detects the amount of rotation of the drum 51 relative to the home position by detecting the amount of rotation of the encoder wheel 53.

[0048] The control unit of the printing device 1 detects the absolute phase (rotational phase) of the drum 51 and the rotating portion 202 of the rotary valve 200 that rotates with the drum 51 by combining the detection results of the two sensors 54, 57.

[0049] Next, an example of a rotary valve will be described with reference to Figures 8 to 14. Figure 8 is an explanatory perspective view of the appearance of the rotary valve, Figure 9 is an explanatory half-sectional perspective view of the same, and Figure 10 is an explanatory enlarged sectional perspective view of the same main part. Figure 11 is an explanatory side view of a fixed part constituting the rotary valve, Figure 12 is an explanatory side view of a second member constituting the same rotary valve, and Figure 13 is an explanatory side view of a first member constituting the same rotary valve. Figure 14 is an explanatory side view of a third member constituting the same rotary valve.

[0050] As described above, the fixed portion 201 of the rotary valve 200 is fixed to the frame 100 of the printing apparatus 1. The fixed portion 201, the home position sensor 57, and the encoder sensor 54 may be fixed to a plurality of separate frames or brackets, respectively.

[0051] The fixed part 201 has a row of grooves 212 arranged in the radial direction and divided into three in the circumferential direction on the side where the fixed part 201 slides against the rotating part 202. Each groove 212 has a through hole 211 and is connected to the suction device 52. Here, the rows of grooves 212 located on the same concentric circle are referred to as groove rows 210A, 210B, 210C, and 210D, respectively.

[0052] The rotating part 202 of the rotary valve 200 is composed of a first member 203, a second member 204, and a third member 205, and they are arranged in the following order from the fixed part 201 side: the third member 205, the first member 203, and the second member 204. However, as shown in Figure 10, in the radial direction, the first member 203 is shaped to cover the outer circumferential surface of the third member 205, and the third member 205 is fitted into the first member 203.

[0053] The second member 204 is provided on the circumferential surface of the disk-shaped member with a plurality of (here, nine) holes 241 (241A-241I) communicating with the suction ports 111 of the drum 51, and each hole 241 has an opening 241a provided on the side surface that contacts the first member 203. The nine holes 241A-241I provided in the circumferential direction communicate with the nine suction ports 111a (111a1-111a9) in the axial direction of the drum 51, and can be connected to each of the plurality of suction holes 112.

[0054] Further, the second member 204 is provided with a plurality of different holes 242 (242A to 242I) on the side surface or the like of the disk-shaped member.

[0055] The holes 242A and 242C1 are formed by a through hole 243a that passes through the second member 204 in the axial direction and a circumferential groove 243b to which the through hole 243a is connected. The holes 242B, 242C2, 242E, 242G1, and 242H are formed by a through hole 243a that passes through the second member 204 in the axial direction. The holes 242D, 242F, 242G2, and 242I are formed by a non-through hole 243c that does not pass through the second member 204 in the axial direction and a hole 243d that extends radially from the non-through hole 243c. These holes 242 also communicate with the suction port 111.

[0056] As shown in FIG. 12, a plurality of holes 241 and the like are provided corresponding to the respective supporting regions 105A, 105B, and 105C.

[0057] In the first member 203, through grooves 231 are provided along the circumferential direction on the side surface of the disk-shaped member in correspondence with each of the supporting regions 105. Here, the grooves 231 are arranged at four locations on concentric circles from the outer periphery toward the center in the radial direction, and the rows of the grooves 231 positioned on the same concentric circle are referred to as groove rows 230A, 230B, 230C, and 230D, respectively.

[0058] Returning to FIG. 16, the rows of openings 241 and holes 242 aligned in the circumferential direction of the second member 204 corresponding to the groove rows 230A to 230D of the first member 203 are respectively referred to as hole rows 240 (240A to 240D) from the outer periphery toward the center.

[0059] Hole 242C1 belonging to hole row 240D of second member 204 and hole 242C2 belonging to hole row 240B are two or more holes 242 that are simultaneously communicated with each other when first member 203 rotates by a unit amount of rotation.

[0060] That is, two or more holes 242C1 and holes 242C2 that are communicated at the same time have different distances from the rotation center O of the first member 203. In other words, two holes 242C1 and holes 242C2 that are communicated at the same time belong to different hole rows 240D and hole rows 240B, respectively, in the multiple hole rows 240 aligned in the radial direction of the second member 204.

[0061] Similarly, hole 242G1 belonging to hole row 240B of second member 204 and hole 242G2 belonging to hole row 240C are two or more holes 242 that are simultaneously communicated with each other when first member 203 rotates by a unit amount of rotation.

[0062] That is, two or more holes 242G1 and holes 242G2 that are communicated at the same time have different distances from the rotation center O of the first member 203. In other words, two holes 242G1 and holes 242G2 that are communicated at the same time belong to different hole rows 240B and hole rows 240C, respectively, in the multiple hole rows 240 aligned in the radial direction of the second member 204.

[0063] In this way, by providing two holes 242C1, 242C2 or 242G1, 242G2 that are simultaneously connected by a unit amount of rotation, one of them can be selected according to the size of the sheet P to be used, and the other hole can be closed with a plug. This makes it easy to accommodate the variety of sizes in the destination country.

[0064] The third member 205 is provided with a through hole 251 that passes through the disk-shaped member and communicates between the groove 212 of the fixed part 201 and the groove 231 of the first member 203 .

[0065] The first member 203, the second member 204, and the third member 205 constituting the rotating portion 202 rotate together with the drum 51 while the sheet P is being transported.

[0066] When switching the suction region (suction area), the first member 203 is rotated relative to the second member 204 and the third member 205 (which always rotate together). This rotation of the first member 203 changes the number of holes 242 of the second member 204 that communicate with the grooves 231 of the first member 203, changing the state of connection of the suction path, and the suction region can be switched and set according to the sheet size.

[0067] Next, switching of the suction area (size switching) by the relative rotation of the first member and the second member will be described with reference to Figures 15 and 16. Figures 15 and 16 are explanatory diagrams for the same explanation, where (a) is an explanatory diagram of the sheet size on the drum and the suction port, (b) is an explanatory side view showing the first member and the second member in a see-through state, and (c) is an enlarged explanatory diagram of (b).

[0068] As described above, the nine holes 241A to 241I provided in the circumferential direction of the second member 204 communicate with the nine suction ports 111a (111a1 to 111a9).

[0069] Therefore, by changing the number of suction ports 111a of the second member 204 that communicate with the grooves 231a of the groove row 230A of the first member 203, the size of the suction region (suction area) in the axial direction perpendicular to the circumferential direction of the drum 51 changes.

[0070] By changing the number of suction ports 111a of the second member 204 that communicate with the grooves 231 of the first member 203, the number of suction holes 112 that face the chambers 113 with which the suction ports 111a communicate changes.

[0071] Furthermore, the suction ports 111b (111b1 to 111b11) of the second member 204 communicate with any of the groove rows 230B to 230D of the first member 203.

[0072] Therefore, by changing the number of suction ports 111b (111b1 to 111b11) that communicate with the grooves 231 of the groove rows 230B to 230D of the first member 203 via the holes 242 of the second member 204, the size of the suction area in the circumferential direction of the drum 51 changes.

[0073] By changing the number of suction ports 111b communicating with the grooves 231 of the first member 203, the number of suction holes 112 facing the chambers 113 with which the suction ports 111b communicate changes.

[0074] For example, as shown in Figures 15(b) and (c), the relative positional relationship between the first member 203 and the second member 204 is such that the groove 231 of the groove row 230A of the first member 203 communicates with the hole 241A of the second member 204, and the groove 231 of the groove row 230D of the first member 203 communicates with the hole 242 of the second member 204.

[0075] At this time, the suction device 52 and the suction port 111a1 of the drum 51 are in communication with each other, and the suction device 52 and the suction port 111b1 of the drum 51 are in communication with each other.

[0076] As a result, as shown in FIG. 16(a), suction is performed from the suction holes 112 in the area BA communicating with the suction port 111a1 and the area BB communicating with the suction port 111b1, and the suction area of ​​the sheet area S1 can be suctioned.

[0077] 16(b) and (c), for example, the first member 203 is rotated in the direction of arrow D relative to the second member 204, and the relative positional relationship between the first member 203 and the second member 204 is changed to a state in which the groove 231 in the groove row 230A of the first member 203 communicates with the holes 241A and 241B of the second member 204, and the groove 231 in the groove row 230D of the first member 203 communicates with the two holes 242 of the second member 204. Note that the black circles in FIGS. 16(b) and (c) indicate new communication points.

[0078] At this time, the suction device 52 and the suction ports 111a1 and 111a2 of the drum 51 are in communication with each other, and the suction device 52 and the suction ports 111b1 and 111b2 of the drum 51 are in communication with each other.

[0079] As a result, as shown in FIG. 16(a), suction is performed from suction holes 112 belonging to area BA leading to suction ports 111a1 and 111a2, and area BB leading to suction ports 111b1 and 111b2, and the suction area of ​​sheet area S2, which is the next size after sheet area S1, can be suctioned.

[0080] Similarly, by changing the relative positional relationship between the first member 203 and the second member 204, that is, the drum 51, the number of suction holes 112 of the drum 51 communicating with the suction device 52 changes, and the suction area can be changed.

[0081] Next, the switching operation of the suction area by the first member will be described with reference to Figures 17 and 18. Figure 17 is an explanatory side view of the rotating part of the rotary valve, and Figure 18 is an enlarged explanatory side view of the same.

[0082] The first member 203 is rotatable, and the suction area can be switched by rotating the first member 203. The rotational position of the first member 203 can be determined by using a plunger 206 or the like, and the tip of the plunger 206 fits into a hole 252 formed in the peripheral surface of the third member 205 according to each position.

[0083] When rotating the first member 203, the plunger 206 is removed from the hole 252, and the first member 203 is rotated relative to the second member 204 and the third member 205 to the desired position, and the tip of the plunger 206 is fitted into the hole 252 at the desired position.

[0084] Next, a rotational motion automation mechanism for the first member in the first embodiment of the present invention will be described with reference to Fig. 19 and Fig. 20. Fig. 19 is an explanatory view for explaining the rotational motion automation mechanism, and Fig. 20 is an enlarged explanatory view of the same.

[0085] The circumferential positions of the through grooves 231 of the groove rows 230A, 230B, 230C, and 230D of the first member 203 are different from those in FIG. 18 and the like described above, but the function is the same.

[0086] The rotational action automation mechanism 300 is a restraining means for restraining the rotation of the first member 203 , and includes a lever mechanism 301 and a linear motion mechanism 302 .

[0087] Lever mechanism 301 is a holding means that holds the relative phase between first member 203 and drum 51, which is a supporting member. Linear motion mechanism 302 is a releasing means that releases the holding (restraint) by the holding means (lever mechanism 301) to enable relative rotation between first member 203 and drum 51.

[0088] The lever mechanism 301 includes a block 311 having a recess 311a. A lever member 312 is attached to the block 311 by a support shaft 313 so as to be rotatable therewith.

[0089] Plunger 206 that restrains first member 203 is attached to one end (tip end) 312a of lever member 312 so as to be movable with a pin 315. The other end (rear end) 312b of lever member 312 faces recess 311a of block 311.

[0090] The plunger 206 is inserted into a guide hole provided in the block 311 so as to be capable of reciprocating motion, and is biased by a spring 207 in the direction of the hole 252 of the third member 205 .

[0091] The linear motion mechanism 302 is fixed to the frame 100. The linear motion mechanism 302 includes a piston 321 that performs linear reciprocating motion by an internal drive source. The piston 321 can advance and retreat relative to a recess 311a of a block 311 of the lever mechanism 301, and can abut against a rear end 312b of the lever member 312. The piston 321 has a cylindrical shape, and its tip is tapered. The spring 207 and the linear motion mechanism 302 constitute a single actuator means that restrains the first member 203 by the holding means (lever mechanism 301) and releases the holding means.

[0092] It should be noted that the first member 203 can be restrained and released by the lever mechanism 301 serving as the holding means, using the linear motion mechanism 302 serving as a single actuator means.

[0093] Next, the operation of the rotational operation automation mechanism 300 will be described with reference to Figures 21 and 22. Figures 21 and 22 are explanatory diagrams for explaining the operation.

[0094] When the first member 203 is rotated, the linear motion mechanism 302 is driven to advance the piston 321. As a result, the piston 321 advances toward the first member 203 and comes into contact with the rear end portion 312b of the lever member 312, as shown in FIG.

[0095] As piston 321 advances further, rear end 312b of lever member 312 is pushed as shown in FIG. 22, causing lever member 312 to rotate in the direction of the arrow around support shaft 313, and in conjunction with this, plunger 206 moves in the direction of the arrow.

[0096] As a result, the plunger 206 comes out of the hole 252 of the third member 205 described in FIG. 18, the locked state between the first member 203 and the drum 51 is released, and the first member 203 and the drum 51 become relatively rotatable.

[0097] In this state, the piston 321 fits into the recess 311a of the block 311, and the lever member 312 is prevented from rotating.

[0098] Therefore, by driving the driving source (driving means) of the drum 51, the first member 203 and the drum 51 (second member 204) rotate relative to each other.

[0099] In this way, by driving and controlling the actuator means of the rotational operation automation mechanism 300 and the driving means that rotates the drum 51, and rotating the first member 203 relative to the drum 51, it becomes possible to automatically change the suction area in response to size changes.

[0100] Although the lever has been described as the means for pulling the plunger 206 out of the hole 252, it may be possible to use a wedge or other means.

[0101] Next, a configuration for acquiring information on the relative phase (relative angle) between the first member and the drum will be described with reference to Fig. 23. Fig. 23 is an explanatory diagram for the same. Note that the first member is shown in a simplified form.

[0102] As explained above in FIG. 6, the phase of the drum 51 can be obtained from the detection results of the encoder sensor 54, which detects the encoder wheel 53 that rotates in sync with the drum 51, and the home position sensor 57, which detects the filler 56 that rotates in sync with the drum 51.

[0103] The first member 203 has a similar configuration, for example, a feeler 456 is provided on the first member 203 side, and a home position sensor 457 is provided on the frame 100 side.

[0104] This makes it possible to calculate the phase difference between the first member 203 and the drum 51 based on the detection signals of the home position sensor 57 of the drum 51 and the home position sensor 457 of the first member 203, and the encoder signal from the encoder sensor 54 of the drum 51, and to obtain the current size setting.

[0105] In addition, the size information of the sheet P contained in the print command received by the printing device 1 is compared with the setting state of the first member 203, and if the comparison results in a mismatch, printing is stopped and a notification to that effect is given.

[0106] Next, a second embodiment of the present invention will be described with reference to Fig. 24. Fig. 24 is a block diagram illustrating a sheet conveying device according to the second embodiment.

[0107] In this embodiment, a matching control means 801, a size information acquisition means 802, and a relative angle information acquisition means 803 are provided.

[0108] The size information acquiring unit 802 acquires size information of the conveyed sheet P. For example, the size information acquiring unit 802 acquires size information of the sheet P included in a print command received by the printing device 1.

[0109] The relative angle information acquiring means 803 acquires information on the number of suction holes 112 that is changed by the relative rotation between the first member 203 and the support member (drum 51).

[0110] The matching control means 801 compares the size information obtained by the size information acquisition means 802 with the information obtained by the relative angle information acquisition means 803, and determines whether or not there is an inconsistency between the size information and the number of suction holes (suction area).

[0111] When a mismatch occurs between the size information and the number of suction holes, the matching control means 801 controls a matching operation to change the relative phase between the first member 203 and the drum 51 and match the size information with the number of suction holes before the sheet conveying operation is started.

[0112] In controlling the matching operation, as described in the first embodiment, the matching control means 801 drives the actuator means 804 which rotates the lever member 312 of the lever mechanism 301 to bring the first member 203 into a rotatable state.

[0113] Then, the matching control means 801 controls the driving of the driving means 58 that rotates the drum 51 to rotate the first member 203 relatively to the drum 51, thereby matching the size information with the number of suction holes (suction area).

[0114] In this manner, the suction region can be automatically switched, and the trouble of switching the suction region can be reduced. [Explanation of symbols]

[0115] 1 Printing device 10 Loading section 20 Printing Department 21 Sheet transport device 22 Liquid discharge part 23 Discharge unit 24 Transfer drum (rotating member) 25 Transfer body (rotating part) 50 Sheet suction device 51 Drums 52 Suction device (suction means) 105, 105A-105C Loading area 111a, 111a1~111a9, 111b1~111b11 Suction port 112 Suction hole 113 Chamber 116A~116D 1st area~4th area 200 Rotary valve (suction area switching device) 201 Fixing part (fixing member) 202 Rotating part (rotating member) 203 First member 204 Second member 205 Third member 231 Groove 241 Hole 300 Rotational movement automation mechanism 301 Lever mechanism (restraint means) 302 Linear motion mechanism (actuator means) 501 Driving means 801 Matching control means 804 Actuator means

Claims

1. a carrier member that carries a sheet on its circumferential surface and is rotated by a driving means; a plurality of suction holes provided in a support area of ​​the support member that supports the sheet; A suction means for suctioning through the suction hole; a first member interposed between the plurality of suction holes and the suction means, the first member being rotated relative to the support member to change the number of the suction holes that communicate with the suction means among the plurality of suction holes; and a restraining means for restraining rotation of the first member relative to the carrier member, The relative rotation of the first member and the carrying member is performed by the driving means; The restraining means is a holding means for holding a relative phase between the first member and the support member; and opening means for opening the retaining means to permit relative rotation of the first member and the carrier member. A sheet suction device comprising:

2. The sheet suction device according to claim 1 is provided. A sheet conveying device comprising:

3. a size information acquiring means for acquiring size information of a sheet to be conveyed; a relative angle information acquiring means for acquiring information on the number of suction holes that is changed by the relative rotation between the first member and the support member; 3. The sheet transport device according to claim 2, further comprising: a means for comparing the size information obtained by the size information obtaining means with the information obtained by the relative angle obtaining means, and when a mismatch occurs, controlling a matching operation for changing the relative phase between the first member and the support member to match them before starting a sheet transport operation.

4. The sheet conveying device according to claim 2 or 3 is provided with the sheet suction device according to claim 1. A printing device comprising:

Images