JP7109296B2 - Printing equipment and box making machine - Google Patents

Description

The present invention relates to a printing apparatus for printing on sheets such as corrugated cardboard sheets, and a box making machine to which the printing apparatus is applied.

For example, a typical box-making machine processes cardboard sheets to produce flat-shaped cardboard boxes. It is composed of parts. In this box making machine, the printing section performs one-color or multi-color printing and has one or a plurality of printing units. The printing unit is a flexographic printing press in which ink in an ink chamber is supplied by an ink supply roll to a printing plate on a printing cylinder, and the ink on the printing plate on the printing cylinder is transferred to a corrugated board sheet for printing.

By the way, as a printing device, it is considered to provide an inkjet printing device in addition to the flexo printing machine. In this case, the flexo printing machine prints characters and patterns on the corrugated cardboard sheet, and the inkjet printer prints, for example, a bar code on the corrugated board sheet. In this inkjet printing apparatus, it is necessary to maintain a predetermined distance between the inkjet head and the printing surface of the cardboard sheet in order to maintain print quality and protect the inkjet head. Therefore, a suction type conveying device is provided, the conveying device conveys the corrugated cardboard sheet while sucking the lower surface of the cardboard sheet, and the printing device prints on the upper surface of the corrugated cardboard sheet conveyed by suction.

As such a conveying device, for example, there is one described in Patent Document 1 below. In the paper sheet conveying apparatus disclosed in Patent Document 1, the interior of the chamber is divided into two by a partition plate, and a high suction force is generated in the upstream chamber on the conveying direction upstream side of the image forming area, thereby forming an image. A low suction force is generated in the downstream chamber corresponding to the area.

JP 2006-089223 A

The above-described conventional paper sheet conveying apparatus reduces adverse effects on the ink ejected onto the image forming area by generating a low suction force in the downstream chamber arranged below the image forming area. It is. However, the inkjet head delivers the ink to the printing surface of the sheet in the form of minute droplets. When the suction force acts on the inkjet head, a negative pressure acts on the ejection section, and the ink ejected from the inkjet head is reduced. Behavior becomes unstable. Further, when a negative pressure acts on the ink in the ejection portion of the inkjet head, it becomes difficult to maintain a stable meniscus state. As a result, the behavior of ink droplets extruded from the nozzles becomes unstable, resulting in a problem of reduced printing accuracy. Moreover, the meniscus cannot be maintained due to the negative pressure, and ink may leak unintentionally.

SUMMARY OF THE INVENTION The present invention is intended to solve the above-described problems, and provides a printing apparatus and a box making machine that suppress deterioration of printing accuracy by suppressing deterioration of printing accuracy by an inkjet head and stably conveying sheets. With the goal.

A printing apparatus according to the present invention for achieving the above object comprises a conveying section that conveys a sheet while sucking the non-printing side of the sheet with a suction section, and a printing unit that prints on the printing side of the sheet with an inkjet head. and a non-suction portion provided at a position facing the inkjet head in the suction portion, wherein the length of the non-suction portion in the conveying direction of the sheet is longer than the ink ejection length region of the inkjet head. It is characterized in that it is set in a preset predetermined non-suction length area.

Therefore, the sheet is conveyed while the non-printing surface is sucked by the suction unit, and printing is performed on the printing surface by the inkjet head. At this time, since the non-suction portion is provided at the position facing the inkjet head, when there is no sheet at the position facing the inkjet head, the suction force does not act on the inkjet head, and the state of the ink is stabilized. It is maintained and the behavior of the ink is stabilized. Then, when the sheet is conveyed to a position facing the inkjet head, ink is properly ejected from the inkjet head onto the printing surface of the sheet. As a result, the ejection state of ink from the nozzles of the inkjet head is stabilized, and the sheet is stably conveyed, thereby suppressing deterioration in printing accuracy. Further, since the non-suction length region of the non-suction portion is longer than the ink ejection length region of the inkjet head, suction force does not act on the ink jet head in the ink ejection length region of the inkjet head, and the nozzles of the inkjet head It is possible to stabilize the ejection state of the ink in.

In the printing apparatus according to the aspect of the invention, a plurality of the printing units are provided along the width direction of the sheet, and a plurality of the non-suction portions are provided along the width direction of the sheet corresponding to the plurality of the printing units. Characterized by

Accordingly, since a plurality of non-suction portions are provided corresponding to a plurality of printing units, the area of the non-suction portions is reduced with respect to the sheet, and the sheet can be conveyed stably.

The printing apparatus according to the present invention is characterized in that a non-suction portion movement adjusting device is provided for moving the non-suction portion in the width direction of the sheet.

Therefore, when the print position is adjusted by moving the printing unit along the width direction of the sheet, the non-suction portion movement adjustment device moves the non-suction portion in the width direction of the sheet according to the adjusted position of the printing unit. position can be easily and precisely adjusted.

In the printing apparatus according to the aspect of the invention, the non-suction section has a blocking plate that partially blocks the suction area of the suction section.

Therefore, since the non-sucking portion is the blocking plate, the structure can be simplified.

In the printing apparatus according to the aspect of the invention, the suction unit has a plurality of divided suction units divided in at least the width direction of the sheet, and the non-suction unit is the divided suction unit provided at a position facing the inkjet head. It is characterized by being a part.

Therefore, since the non-sucking portion is the divided suction portion, the position of the non-sucking portion can be easily changed.

The printing apparatus according to the aspect of the invention is characterized in that the non-suction portion is provided over the entire width direction along which the sheet is conveyed.

Therefore, since the non-suction portion is provided in the entire width direction along which the sheet is conveyed, when a plurality of printing units are arranged in the width direction of the sheet, it is sufficient to provide one non-suction portion. Simplification can be achieved.

In the printing apparatus according to the aspect of the invention, the printing unit is provided with a driving body that is rotatable and can come into contact with the printing surface of the sheet.

Therefore, when the sheet is conveyed and the printing surface of the sheet is printed by the inkjet head, the lower surface of the sheet is not sucked at the position of the sheet facing the inkjet head, but the printing surface is driven and rotated by the driving body. Since the sheets are in contact with each other, the sheet is pressed against the sheet conveying surface by the driving member and is given a conveying force. Therefore, the sheet is stably conveyed by the driving body, and the inkjet head can perform printing with high accuracy while maintaining a constant distance from the printing surface of the sheet.

The printing apparatus according to the present invention is characterized in that a predetermined constant gap preset according to the thickness of the sheet is ensured between the sheet conveying surface of the conveying section and the driving member.

Therefore, when the sheet is conveyed on the sheet conveying surface, the sheet on the sheet conveying surface enters a certain gap secured between the sheet conveying surface and the driving member, so that the driving member moves the printing surface of the sheet. The sheet can be stably conveyed by pressing, and the distance between the sheet and the inkjet head can be kept constant to perform high-precision printing by the inkjet head.

The printing apparatus according to the aspect of the invention is characterized in that a plurality of the printing units are arranged at predetermined intervals in the sheet conveying direction.

Therefore, even if the printing positions of the plurality of printing units with respect to the printing surface of the sheet are close to the width direction of the sheet, since the plurality of printing units are arranged in the sheet conveying direction, the printing timing for each printing unit is shifted. , the printing unit can print at a predetermined position with high accuracy.

The printing apparatus of the present invention is characterized in that a flexographic printing unit is arranged downstream of the printing unit in the sheet conveying direction.

Therefore, since the printing unit prints on the printed surface of the sheet and then the flexographic printing unit prints, it is possible to secure the drying time of the ink on the printed surface of the sheet by the printing unit. , the print quality can be improved.

The box-making machine of the present invention includes a paper feed unit that supplies sheet materials for box-making, a printing unit that prints on the sheet materials for box-making, and a ruled line processing on the surface of the sheet materials for box-making. A paper discharge unit that performs grooving together with the sheet material, a folder gluer unit that forms a box by folding the sheet material for box making and joining the ends, and after counting and stacking the boxes, every predetermined number and a counter ejector section that ejects the printed material to the outside, and the printing section includes the printing device.

Therefore, in the printing unit, the sheet is provided with a non-suction portion at a position facing the inkjet head. The ink state is maintained stably. Then, when the sheet is conveyed to a position facing the inkjet head, ink is properly ejected from the inkjet head onto the printing surface of the sheet. As a result, the ejection state of ink from the nozzles of the inkjet head is stabilized, and the sheet is stably conveyed, thereby suppressing deterioration in printing accuracy.

According to the printing apparatus and the box making machine of the present invention, it is possible to suppress deterioration of printing accuracy due to the nozzles of the inkjet head, and to stably convey the sheet, thereby suppressing deterioration of printing accuracy.

FIG. 1 is a schematic diagram showing the box making machine of the present embodiment. FIG. 2 is a side view showing the first printing unit of this embodiment. FIG. 3 is a plan view showing the first printing unit of this embodiment. FIG. 4 is a side view showing the printing unit. FIG. 5 is a plan view showing the printing unit. FIG. 6 is a side view showing a modification of the printing unit of this embodiment. FIG. 7 is a plan view showing a modification of the printing unit. FIG. 8 is a plan view showing the arrangement range of the blocking plate as the non-suction portion in the printing apparatus. 9 is a cross-sectional view taken along line IX-IX of FIG. 8. FIG. FIG. 10 is a plan view showing a first modification of the blocking plate as the non-suction portion in the printing apparatus. 11 is a cross-sectional view taken along line XI-XI of FIG. 10. FIG. FIG. 12 is a plan view showing a second modification of the blocking plate as the non-suction portion in the printing apparatus.

Preferred embodiments of a printing apparatus and a box making machine according to the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that the present invention is not limited by this embodiment, and when there are a plurality of embodiments, the present invention includes a combination of each embodiment.

FIG. 1 is a schematic diagram showing the box making machine of the present embodiment.

In this embodiment, as shown in FIG. 1, a box making machine 10 manufactures a cardboard box B by processing a cardboard sheet S. As shown in FIG. The box making machine 10 includes a paper feeding section 11, a printing section 12, a paper discharging section 13, a die cutting section 14, a folder, and a paper feeding section 11, a printing section 12, a paper discharging section 13, a die cutting section 14, and a folder. It is composed of a gluer section 15 and a counter ejector section 16 .

The paper feed unit 11 holds a large number of plate-like corrugated cardboard sheets S stacked in the vertical direction, feeds out the corrugated cardboard sheets S one by one, and sends them to the printing unit 12 at a constant speed. The printing section 12 has a first printing section 21 and a second printing section 22 . The first printing section 21 has four ink jet printing units 21A, 21B, 21C, 21D and the second printing section 22 has four flexographic printing units 22A, 22B, 22C, 22D.

The first printing unit 21 is capable of single-color printing or multi-color printing. In the first printing unit 21, two inkjet printing units 21A and 21C are arranged along the width direction of the corrugated cardboard sheet S, and two inkjet printing units 21B and 21D are arranged along the width direction of the corrugated cardboard sheet S. placed. Also, two ink jet printing units 21A and 21C and two ink jet printing units 21B and 21D are arranged along the transport direction T with a predetermined interval. The second printing unit 22 is capable of multi-color printing (in this embodiment, four-color printing) on the cardboard sheet S. As shown in FIG. In the second printing section 22, four flexographic printing units 22A, 22B, 22C, and 22D are arranged along the transport direction T at predetermined intervals. In this embodiment, the first printing unit 21 prints a bar code or the like on the printing surface of the cardboard sheet S, and the second printing unit 22 prints patterns such as characters on the printing surface of the cardboard sheet S.

The paper discharge unit 13 applies ruled line processing to the corrugated cardboard sheet S and groove processing. The die cut portion 14 is for punching the cardboard sheet S for manual holes. The folder gluer unit 15 folds the cardboard sheet S while moving it in the transport direction T, and joins both ends in the width direction to form a flat cardboard box B. As shown in FIG. The counter ejector section 16 counts and stacks the cardboard boxes B manufactured by the folder gluer section 15, and then sorts and discharges them into a predetermined number of batches.

FIG. 2 is a side view showing the first printing unit of this embodiment, and FIG. 3 is a plan view showing the first printing unit of this embodiment.

In this embodiment, as shown in FIGS. 2 and 3, the first printing unit 21 prints a barcode on the printing surface (surface) of the corrugated cardboard sheet S, and includes four inkjet printing units (hereinafter referred to as , printing units) 21A, 21B, 21C and 21D.

The first printing unit 21 is arranged above the conveying unit 31 so as to face it. The transport unit 31 continuously transports the corrugated cardboard sheets S supplied from the paper feed unit 11 (see FIG. 1) along the transport direction T at predetermined intervals. The transport unit 31 transports the cardboard sheet S while sucking the non-printing surface (lower surface) thereof. The transport section 31 has a suction section 32 and a transport belt 33 .

The suction unit 32 is arranged along the transport direction T of the corrugated cardboard sheet S and has a width larger than the width of the corrugated board sheet S to be transported. Although not shown, the suction unit 32 is a sealed hollow box-shaped suction box, and is configured by forming a large number of suction holes in the upper surface of the suction box. A suction blower 34 is connected to the suction portion 32 . Therefore, by driving the suction blower 34, the air in the suction box of the suction unit 32 can be sucked, and suction force can be generated in each suction hole.

The transport belt 33 is an endless belt, and is supported by being looped around a drive roller 35 and a plurality of guide rollers (not shown). The conveying belt 33 is arranged so as to contact the upper surface of the suction box of the suction unit 32, and is formed with a large number of through holes (not shown). Therefore, when a suction force acts on the suction box of the suction unit 32 , this suction force acts on the upper surface of the conveyor belt 33 through each suction hole of the suction box and each through hole of the conveyor belt 33 . Then, the corrugated cardboard sheet S is conveyed while being attracted to the upper surface of the conveying belt 33 moving by the drive roller 35 .

The first printing section 21 has four printing units 21A, 21B, 21C, and 21D. A plurality of the first printing units 21 are arranged at predetermined intervals in the transport direction T of the cardboard sheet S, and a plurality of the first printing units 21 are arranged in the width direction of the cardboard sheet S. As shown in FIG. That is, the first printing unit 21A and the third printing unit 21C are arranged side by side in the width direction of the cardboard sheet S, and the second printing unit 21B and the fourth printing unit 21D are arranged side by side in the width direction of the cardboard sheet S. be done. The first printing unit 21A and the third printing unit 21C, and the second printing unit 21B and the fourth printing unit 21D are arranged at a predetermined interval in the transport direction T of the cardboard sheet S.

As shown in FIGS. 1 and 3, the corrugated board sheet S is formed by gluing a corrugated core between a front liner and a back liner. Two folding lines 301 and 302 are formed in the corrugated cardboard sheet S in the previous process of the box making machine 10 . These folding lines 301 and 302 are for folding the flaps when the manufactured cardboard box B is assembled later. Then, the corrugated cardboard sheet S is formed with ruled lines 311 , 312 , 313 , and 314 in the paper discharge section 13 . After that, the cardboard sheet S is formed with grooves at the positions of the ruled lines 312, 313, and 314, and is cut at the position of the ruled line 311 to form margin strips. Therefore, the cardboard sheet S is composed of four sheet pieces 321, 322, 323, and 324 bordering on the ruled lines 312, 313, and 314 (grooves). The sheet pieces 321, 322, 323, 324 each have a pair of flaps 321a, 321b, 322a, 322b, 323a, 323b, 324a, 324b.

The first printing unit 21A prints on the sheet piece 321 or its flaps 321a and 321b, the second printing unit 21B prints on the sheet piece 322 or its flaps 322a and 322b, and the third printing unit 21C prints on the sheet Printing is performed on the strip 323 or its flaps 323a and 323b, and the fourth printing unit 21D prints on the sheet strip 324 or its flaps 324a and 324b. For example, when the cardboard sheet S is conveyed along the conveying direction T, first, the first printing unit 21A prints the barcode B1 on the sheet piece 321, and at the same time, the third printing unit 21C prints the sheet piece 323, the flap 323a, and the sheet piece 323a. Barcodes B3, B3a, and B3b are printed on 323b. When the cardboard sheet S is further transported along the transport direction T, next, the second printing unit 21B prints the barcode B2 on the sheet piece 322, and the fourth printing unit 21D prints the barcode B4 on the sheet piece 324. to print.

The first printing unit 21A and the third printing unit 21C are movable in the width direction of the corrugated cardboard sheet S by the first movement adjusting devices 41 and 43, and can adjust the print position in the width direction of the corrugated cardboard sheet S. The second printing unit 21B and the fourth printing unit 21D can be moved in the width direction of the cardboard sheet S by the first movement adjustment devices 42 and 44, and can adjust the print position in the width direction of the cardboard sheet S. Further, the first printing unit 21A and the third printing unit 21C are movable in the vertical direction orthogonal to the printing surface of the corrugated cardboard sheet S by the second movement adjusting device 45, and adjust the printing distance with respect to the printing surface of the corrugated cardboard sheet S. be able to. The second printing unit 21B and the fourth printing unit 21D are movable in the vertical direction orthogonal to the printing surface of the corrugated cardboard sheet S by the second movement adjusting device 46, and the printing distance to the printing surface of the corrugated cardboard sheet S can be adjusted. can.

The printing units 21A, 21B, 21C, and 21D have almost the same configuration, and include support frames 51, 52, 53, and 54, inkjet heads 61, 62, 63, and 64, and drivers 71, 72, 73, and 74. , drives 81 and 82 . That is, the printing units 21A, 21B, 21C, and 21D have ink jet heads 61, 62, 63, and 64 and driving bodies 71, 72, 73, and 74 mounted on supporting frames 51, 52, 53, and 54, and driving devices The driving bodies 71 and 73 can be synchronously rotated by 81 , and the driving bodies 72 and 74 can be synchronously rotated by the driving device 82 .

The printing units 21A, 21B, 21C, and 21D will be described below, but since the printing units 21A, 21B, 21C, and 21D have substantially the same configuration, only the first printing unit 21A will be described. 4 is a side view showing the printing unit, and FIG. 5 is a plan view showing the printing unit. In addition, FIG. 4 omits the side frame on the front side.

As shown in FIGS. 4 and 5, in the first printing unit 21A, the support frame 51 is supported so as to face the conveying path of the cardboard sheet S, that is, the upper surface of the conveying belt 33. As shown in FIGS. The support frame 51 includes a pair of left and right side frames 101 , a connecting frame 102 connecting the pair of left and right side frames 101 , and a pair of support frames 51 arranged between the pair of left and right side frames 101 and connected to the connecting frame 102 . mounting frame 103. The side frames 101 have a substantially triangular shape with an acute angle on the front side in the conveying direction T of the corrugated cardboard sheet S. The side frames 101 extend along the conveying direction T and the vertical direction of the corrugated cardboard sheet S and are spaced apart in the width direction of the corrugated cardboard sheet S at predetermined intervals. are placed.

The connecting frame 102 has a rectangular shape and is arranged along the width direction and the vertical direction of the cardboard sheet S. As shown in FIG. The connecting frame 102 connects the ends of the pair of left and right side frames 101 on the rear side in the conveying direction T of the corrugated cardboard sheet S via connecting pieces 104 . The side frame 101 and the connection frame 102 are orthogonally connected. The pair of mounting frames 103 have a rectangular shape, and are arranged along the transport direction T and the vertical direction of the cardboard sheet S and are spaced apart in the width direction of the cardboard sheet S at a predetermined interval. The pair of mounting frames 103 are connected to the connecting frame 102 at their rear ends in the transport direction T of the cardboard sheet S, and support the inkjet head 61 at their front ends in the transport direction T of the cardboard sheet S. . In addition, the pair of left and right side frames 101 are connected by a reinforcing frame 105 at the ends on the front side in the conveying direction T of the corrugated cardboard sheet S. As shown in FIG.

The inkjet head 61 is arranged in a space surrounded by a pair of left and right side frames 101 , a connecting frame 102 and a reinforcing frame 105 , and supported by the connecting frame 102 via a pair of mounting frames 103 . The inkjet head 61 has a head main body 61a at its lower portion, and the head main body 61a performs printing on a predetermined ink ejection width region Wp in the width direction of the corrugated cardboard sheet S on the printing surface of the corrugated cardboard sheet S. can be done. The inkjet head 61 extrudes ink from the nozzles of the head body 61a and causes the extruded ink to reach the printing surface of the corrugated cardboard sheet S as fine droplets. A piezo method or a thermal method) can be used. Here, the ink ejection width region Wp is a region in the width direction of the corrugated cardboard sheet S in which one or more nozzles are arranged in the head main body 61a.

The driving bodies 71 are arranged on both sides of the inkjet head 61 in the width direction of the cardboard sheet S, and are rotatably supported by the support frame 51 so that they can come into contact with the printing surface of the cardboard sheet S. As shown in FIG. The driving body 71 has a driving roller 111 , driven rollers 112 and 113 , an idler 114 and a driving belt 115 . As shown in FIG. 3 , the driving device 81 has a driving motor 116 , a driving shaft 117 and bearings 118 and drives and rotates the driving body 71 .

A pair of left and right printing machine frames 121 and 122 are arranged on both sides of the cardboard sheet S in the transport direction T. As shown in FIG. The drive motor 116 is arranged on one side of the printing press frame 121 and the bearing 118 is arranged on the other side of the printing press frame 122 . The drive shaft 117 is arranged along the width direction of the corrugated cardboard sheet S, one axial end is drivingly connected to the drive motor 116 , and the other axial end is rotatably supported by the bearing 118 .

As shown in FIGS. 4 and 5 , the drive shaft 117 horizontally passes through the upper portions of the side frames 101 and the mounting frame 103 on the rear side, and extends between the left and right side frames 101 and the inkjet heads 61 . A pair of driving rollers 111 are fixed respectively. The driven rollers 112 and 113 are rotatably supported by support shafts 123 and 124 between the left and right side frames 101 and the inkjet head 61 at the front and rear lower portions of the left and right side frames 101 . The idlers 114 are rotatably supported on the upper portions of the left and right side frames 101 by support shafts 125 between the left and right side frames 101 and the inkjet heads 61 . The drive belt 115 is an endless belt that is looped around the outside of the drive roller 111 and the driven rollers 112 and 113 and pressed by the idler 114 from the outside.

Therefore, as shown in FIGS. 3 to 5, when the drive motor 116 is driven to drive and rotate the drive shaft 117 in the normal rotation direction, the drive roller 111 is driven to rotate together with the drive shaft 117, causing the drive roller 111 and the driven roller 112 to rotate. , 113 can be driven to rotate. In this case, the rotational speed (peripheral speed) of the drive belt 115 is the same as the moving speed (peripheral speed) of the conveying belt 33 that sucks and conveys the cardboard sheet S. However, the rotational speed (peripheral speed) of the drive belt 115 may be slightly higher than the moving speed of the conveyor belt 33 . Further, the portion of the drive belt 115 supported by the two driven rollers 112 and 113 protrudes vertically below the support frame 51, that is, toward the conveying belt 33 side. A predetermined constant gap H is secured between the upper surface of the conveyor belt 33 that sucks and conveys the corrugated cardboard sheet S and the lower surface of the drive belt 115 projecting downward from the support frame 51 . The predetermined constant gap H is set according to the thickness of the corrugated cardboard sheet S to be conveyed, and is basically set to the thickness of the corrugated cardboard sheet S to be conveyed or an amount larger than the thickness of the corrugated cardboard sheet S. be done.

However, the predetermined constant gap H may be adjusted according to the rigidity of the cardboard sheet S. For example, when the rigidity of the cardboard sheet S is high, the predetermined constant gap H is adjusted to be slightly smaller than the thickness of the cardboard sheet S (fixed gap H=thickness of the cardboard sheet S−adjustment amount H1). The corrugated cardboard sheet S having a high height is straightened so as to be pressed with a stronger pressure by the driving belt 115.例文帳に追加On the other hand, when the rigidity of the cardboard sheet S is low, the predetermined constant gap H is adjusted to be slightly larger than the thickness of the cardboard sheet S (fixed gap H=thickness of the cardboard sheet S+adjustment amount H2). The corrugated cardboard sheet S which is short is straightened so as to be pressed by the drive belt 115 with a weak pressure. That is, by adjusting the size of the predetermined constant gap H, that is, the pressure suppressed by the drive belt 115, according to the rigidity of the warped corrugated cardboard sheet S, the corrugated cardboard sheet S can be properly bent without being damaged. It is possible to correct the warp and convey it.

The adjustment amount H2 of the predetermined constant gap H is set as follows. When the target print position accuracy of the inkjet head = A [mm], the maximum value of the transport speed of the corrugated cardboard sheet S = S [m/sec], and the flying speed of ink droplets from the inkjet = D [m/sec], it is constant. The adjustment amount H2 of the gap H is calculated by the following formula.
H2 = A x (D/S)
For example, if A = 0.127 mm (200 dpi), S = 7 m/sec, and D = 10 m/sec, then H2 = 0.181 mm, and the constant gap H is made larger than the thickness of the cardboard sheet S up to 0.181 mm. can do.
Here, as the transport speed of the corrugated cardboard sheet S increases, the adjustment amount H2 decreases, and as the flying speed of the ink droplets increases, the adjustment amount H2 increases.

The first movement adjustment device 41 has a screw shaft 131 , a nut 132 , a driven gear 133 and a drive motor 134 . A mounting frame 141 extending rearward in the transport direction T of the cardboard sheet S from the connecting frame 102 is fixed to the support frame 51 . The screw shaft 131 is arranged along the width direction of the corrugated cardboard sheet S, one axial end is fixed to a mounting member 142 arranged on the printer frame 121 side, and the other axial end is fixed to the printer frame 122 . It is fixed to a mounting member 143 arranged on the side. The nut 132 is screwed onto the screw shaft 131, and the driven gear 133 is fixed. The driven gear 133 is rotatably supported by the mounting frame 141 by the support member 144 so as not to be relatively movable in the axial direction. The drive motor 134 is fixed to the mounting frame 141 and the drive gear 145 meshes with the driven gear 133 .

Therefore, when the drive motor 134 is driven to drive and rotate the drive gear 145, the driven gear 133 meshing with the drive gear 145 rotates, and the nut 132 integrated with the driven gear 133 rotates. When the nut 132 rotates, the nut 132 moves in the axial direction of the threaded shaft 131 to which it is screwed while rotating. Then, the mounting frame 141 to which the driven gear 133 integrated with the nut 132 is fixed, that is, the inkjet head 61 supported by the support frame 51 moves in the axial direction of the screw shaft 131 . That is, the first movement adjustment device 41 moves the inkjet head 61 along the width direction of the corrugated cardboard sheet S by moving the first printing unit 21A in the axial direction of the screw shaft 131, thereby causing the inkjet head 61 to eject ink. The width region Wp can be adjusted in the width direction.

The second movement adjusting device 45 has lifting devices 151 and 152 , a lifting frame 153 and lifting support frames 154 and 155 . The elevating frame 153 is arranged along the width direction of the corrugated cardboard sheet S. An elevating support frame 154 arranged on the side of the printing machine frame 121 is fixed to one end in the longitudinal direction, and the printing machine frame is fixed to the other end in the axial direction. A lift support frame 155 arranged on the 122 side is fixed. The drive motor 116 and the mounting member 142 are mounted on the lift support frame 154 , and the bearing 118 and the mount member 143 are mounted on the lift support frame 155 . The lifting device 151 supports one end of the lifting frame 153 in the longitudinal direction and can be lifted. The lifting device 152 supports the other end of the lifting frame 153 in the longitudinal direction and can lift. The elevating frame 153 is fixed to the mounting frame 141 .

Therefore, when the lifting devices 151 and 152 are driven to lift the lifting frame 153, the first printing unit 21A and the first movement adjusting device 41 connected to the lifting frame 153 can be lifted. Then, by moving up and down the driving body 71 mounted on the first printing unit 21A, the vertical position of the driving body 71 is adjusted, and the constant gap H between the upper surface of the conveying belt 33 and the lower surface of the driving belt 115 is adjusted. You can adjust the amount of

Although the printing units 21B, 21C, and 21D are not described, they have substantially the same configuration as the first printing unit 21A.

In the printing units 21A, 21B, 21C, and 21D of the first printing section 21, the driving bodies 71 are not limited to those described above. FIG. 6 is a side view showing a modification of the printing unit of this embodiment, and FIG. 7 is a plan view showing a modification of the printing unit.

In a modification of this embodiment, the first printing unit 21A includes a support frame 51, an inkjet head 61, a driver 161, and a driver 81, as shown in FIGS. That is, in the first printing unit 21A, the inkjet head 61 and the driving body 161 are mounted on the support frame 51, and the driving body 161 can be driven and rotated by the driving device 81. FIG.

The driving bodies 161 are arranged on both sides of the inkjet head 61 in the width direction of the cardboard sheet S, and are rotatably supported by the support frame 51 so that they can come into contact with the printing surface of the cardboard sheet S. The drive body 161 has drive rollers 162 and 163 , a drive sprocket 164 , driven sprockets 165 and 166 , an idler 167 and a chain belt 168 . The driving device 81 has a driving motor 116 , a driving shaft 117 and bearings 118 and drives and rotates the driving body 161 .

The drive shaft 117 horizontally penetrates through the rear side upper portions of the side frame 101 and the mounting frame 103, and a pair of left and right drive sprockets 164 are fixed between the left and right side frames 101 and the inkjet heads 61, respectively. there is A pair of left and right drive rollers 162 and 163 are rotatably supported by support shafts 171 and 172 on the front and rear lower portions of the left and right side frames 101 between the left and right side frames 101 and the inkjet head 61 . A pair of left and right driven sprockets 165 and 166 are supported by support shafts 171 and 172 so as to rotate integrally with a pair of left and right driving rollers 162 and 163 . The idlers 167 are rotatably supported on the upper portions of the left and right side frames 101 by support shafts 173 between the left and right side frames 101 and the inkjet heads 61 . The chain belt 168 is an endless chain belt, which is wound around the outside of the drive sprocket 164 and the driven sprockets 165 and 166 and pressed by the idler 167 from the outside.

Therefore, when the drive motor 116 is driven to drive and rotate the drive shaft 117 in the forward direction, the drive sprocket 164 is driven to rotate together with the drive shaft 117, the chain belt 168 wound around the drive sprocket 164 is driven, and the driven sprocket is driven. 165 and 166 can be driven to rotate. Then, the drive rollers 162, 163 integrated with the driven sprockets 165, 166 can be driven. The two drive rollers 162 and 163 are arranged below the support frame 51 in the vertical direction, that is, on the conveyor belt 33 side. A constant gap H is ensured between the upper surface of the conveying belt 33 that sucks and conveys the corrugated cardboard sheet S and the lower portions of the drive rollers 162 and 163 projecting downward from the support frame 51 . The fixed gap H is large enough to allow the driving rollers 162 and 163 to contact the upper surface (printing surface) of the corrugated cardboard sheet S conveyed by being attracted to the upper surface of the conveying belt 33 .

In the above-described embodiment, the number of driven rollers 112 and 113 is not limited to two, and may be one or three or more. Moreover, in the modification of the embodiment described above, the number of drive rollers 162 and 163 is not limited to two, and may be one or three or more.

By the way, as shown in FIG. 2, the above-described transport section 31 transports the corrugated cardboard sheet S while sucking the lower surface (non-printing surface) thereof, and the first printing section 21 includes inkjet heads 61, 62, 63, and 64. A cardboard sheet S is printed. Therefore, the inkjet heads 61, 62, 63, and 64 do not receive the suction force from the transport unit 31 when there is a cardboard sheet S at the facing position, but when there is no cardboard sheet S at the facing position, the ink jet heads 61, 62, 63, and 64 are Suction force is received from 31. When the inkjet heads 61, 62, 63, and 64 receive the suction force, the behavior of the ink ejected from the ejection section becomes unstable. In addition, the ink maintained in the meniscus state at the tip of the nozzle vibrates, and the behavior of ink droplets ejected from the nozzle becomes unstable, resulting in a decrease in printing accuracy.

Therefore, in the first printing section 21 of the present embodiment, non-suction sections are provided at positions facing the inkjet heads 61 , 62 , 63 , 64 in the suction section 32 . 8 is a plan view showing the arrangement range of the blocking plate as the non-suction portion in the printing apparatus, and FIG. 9 is a cross-sectional view taken along line IX-IX in FIG.

As shown in FIGS. 8 and 9 , in the first printing section 21 , the transport section 31 has a suction section 32 and a transport belt 33 . The suction unit 32 is arranged along the conveying direction T of the corrugated cardboard sheet S, is configured by forming a large number of suction holes 32a in the upper surface of the suction box, and is connected to a suction blower 34 (see FIG. 2). The conveying belt 33 is arranged so as to contact the upper surface of the suction box of the suction unit 32, has a large number of through holes 33a, and is movable by a drive roller 35 (see FIG. 2). Therefore, when a suction force acts on the suction portion 32 , this suction force acts on the upper surface of the conveyor belt 33 through the many suction holes 32 a and the through holes 33 a of the conveyor belt 33 . The cardboard sheet S on the upper surface of the conveying belt 33 is conveyed along the conveying direction T by being attracted to the upper surface of the moving conveying belt 33 .

The first printing unit 21A and the third printing unit 21C have inkjet heads 61 and 63. The inkjet heads 61 and 63 eject a predetermined amount of ink onto the printing surface of the cardboard sheet S in the width direction of the cardboard sheet S. Printing is performed on the width area Wp and a predetermined printing length in the transport direction of the cardboard sheet S. As shown in FIG.

The first printing section 21 is provided with a blocking plate 181 as a non-suction section at a position facing the inkjet heads 61 and 63 in the suction section 32 . The blocking plate 181 blocks part of the suction area in the suction section 32 and is fixed to the lower portion of the suction hole 32 a provided in the suction section 32 . In this embodiment, the blocking plate 181 is provided over the entire widthwise transport area W in which the corrugated cardboard sheet S is transported. In addition, the blocking plate 181 is set in a predetermined non-suction length region Ls that is longer than the ink discharge length region Lp in the transport direction T of the corrugated cardboard sheet S. Here, the ink ejection length region Lp is a region in which one or more nozzles are arranged in the head main body 61a in the direction in which the corrugated cardboard sheet S is conveyed. Note that the non-suction length region Ls is related to hindrance to the transportability of the corrugated cardboard sheet S, and is preferably set as follows. Here, the area in the length direction that does not hinder transportability is an area in which the corrugated cardboard sheet S sucked by the suction unit 32 can be properly conveyed even if the non-suction length area Ls is secured.
Ink ejection length region Lp<Non-sucking length region Ls<Longitudinal region that does not hinder transportability

Therefore, in the first printing unit 21A, the corrugated cardboard sheet S is conveyed by the conveying belt 33 while its lower surface is sucked by the suction unit 32, and at a position facing the inkjet head 61, the inkjet head 61 presses against the printing surface. printing is done. At this time, since the suction portion 32 facing the inkjet head 61 is blocked by the blocking plate 181, the suction force does not act on the inkjet head 61, and the inkjet head 61 maintains a stable ink state. be done. When the corrugated cardboard sheet S is conveyed to a position facing the inkjet head 61 , ink is properly ejected from the inkjet head 61 onto the printing surface of the corrugated cardboard sheet S.

The shape and arrangement of the blocking plate 181 as the non-sucking portion are not limited to those described above. FIG. 10 is a plan view showing a first modification of the blocking plate as the non-suction portion in the printing apparatus, and FIG. 11 is a cross-sectional view taken along line XI-XI of FIG.

In the first modified example of the present embodiment, as shown in FIGS. 10 and 11, the first printing unit 21 has a plurality of blocking plates as non-suction units at positions facing the inkjet heads 61 and 63 in the suction unit 32. 182, 183 are provided. The blocking plates 182 and 183 block part of the suction area in the suction section 32 and are arranged below the suction holes 32 a provided in the suction section 32 . In this embodiment, the blocking plates 182 and 183 are provided at predetermined intervals in the width direction of the cardboard sheet S corresponding to the plurality of printing units 21A and 21C. That is, a closing plate 182 is provided corresponding to the inkjet head 61 of the first printing unit 21A, and a closing plate 183 is provided corresponding to the inkjet head 63 of the third printing unit 21C.

The blocking plates 182 and 183 are set in a predetermined non-suction width region Ws in which the length (width) in the width direction of the corrugated cardboard sheet S is longer than the ink discharge width region Wp. In addition, the blocking plates 182 and 183 are set in a predetermined non-suction length region Ls that is longer than the ink ejection length region Lp in the transport direction T of the corrugated cardboard sheet S. Here, the area in the width direction that does not impede transportability is an area in which the corrugated cardboard sheet S sucked by the suction unit 32 can be properly conveyed even if the non-suction width area Ws is secured.
Ink ejection width region Wp<Non-suction width region Ws<Width direction region that does not hinder transportability

In addition, the blocking plate 182 is movable in the width direction of the corrugated cardboard sheet S by the non-suction portion movement adjusting device 184 . The non-suction portion movement adjustment device 184 has a nut 185 , a screw shaft 186 and a drive motor 187 . A nut 185 is fixed to the lower surface of the closing plate 182 , and a screw shaft 186 arranged along the width direction of the corrugated cardboard sheet S is screwed into the nut 185 . The drive motor 187 can drive and rotate the screw shaft 186 . Although not shown, the blocking plate 183 can be moved in the width direction of the corrugated cardboard sheet S independently of the blocking plate 182 by a non-suction portion movement adjusting device.

Therefore, when the drive motor 187 is driven to drive and rotate the screw shaft 186 , the closing plate 182 moves via the nut 185 screwed onto the screw shaft 186 . That is, the first printing unit 21 adjusts the width direction position of the corrugated cardboard sheet S in the first printing unit 21A (inkjet head 61) by the first movement adjusting device 43 according to the printing position of the barcode on the corrugated cardboard sheet S. . The non-suction portion movement adjustment device 184 adjusts the width direction position of the cardboard sheet S on the closure plate 182 according to the printing position of the first printing unit 21A (inkjet head 61).

Also, although the blocking plates 181, 182, and 183 are provided as non-sucking portions, the non-sucking portions are not limited to this configuration. FIG. 12 is a plan view showing a second modification of the blocking plate as the non-suction portion in the printing apparatus.

In the second modification of the present embodiment, as shown in FIG. 12 , in the first printing section 21 , the conveying section 31 has a suction section 190 and a conveying belt 33 . The suction unit 190 has a plurality of divided suction units 191 that are divided in the width direction of the cardboard sheet S. As shown in FIG. One divided suction portion 191 provided at a position facing the inkjet head 61 is used as a non-suction portion. The divided suction portion 191 as a non-suction portion is divided into a plurality of space portions 193 in the width direction of the corrugated cardboard sheet S by a partition plate 192, and a large number of suction holes 193a are formed in the upper surface portion. A suction blower (not shown) is individually connected to the . 8, the split suction part 191 applied as a non-suction part is arranged in the same position as the closure plate 181 in the conveying direction T of the corrugated cardboard sheet S, and the closure plate 181 (divided suction part 191), the upstream side and the downstream side in the transport direction T are suction units.

Therefore, in the first printing unit 21, the position of the first printing unit 21A (inkjet head 61) is adjusted in the width direction of the cardboard sheet S according to the printing position of the barcode on the cardboard sheet S. The suction unit 190 stops driving a suction blower connected to a corresponding predetermined space 193 in the divided suction unit 191 according to the printing position of the first printing unit 21A (inkjet head 61), thereby forming a non-suction unit. and

The operation of the printing unit 12 of this embodiment will be described below.

As shown in FIG. 1, a large number of cardboard sheets S are vertically stacked on the paper feed table of the paper feed unit 11, and the lowest cardboard sheet S is fed forward. Then, the corrugated cardboard sheet S is supplied toward the printing section 12 at a predetermined constant speed. As shown in FIGS. 2 and 3, in the printing unit 12, the conveying unit 31 conveys the corrugated cardboard sheet S on the conveying belt 33 along the conveying direction T while the suction unit 32 sucks it from below. At this time, in the printing unit 12, the first printing unit 21 prints, for example, a barcode on the printing surface of the cardboard sheet S. As shown in FIG. Then, the second printing unit 22 prints characters, for example, on the printing surface of the cardboard sheet S. As shown in FIG.

The printed corrugated cardboard sheet S is conveyed by the conveying unit 31, and as shown in FIG. Subsequently, the die cutting section 14 punches the cardboard sheet S for manual holes, and the folder gluer section 15 folds the cardboard sheet S and joins both ends in the width direction to form a flat cardboard box. form B. Thereafter, the counter ejector unit 16 counts and stacks the manufactured cardboard boxes B, sorts them into a predetermined number of batches, and discharges them.

Here, the operation of the printing units 21A, 21B, 21C, and 21D in the first printing section 21 will be specifically described.

As shown in FIGS. 2 and 3, when the cardboard sheet S is conveyed to the positions of the first printing unit 21A and the third printing unit 21C, the first printing unit 21A first prints the barcode B1 on the sheet piece 321. At the same time, the third printing unit 21C prints barcodes B3, B3a and B3b on the sheet piece 323 and the flaps 323a and 323b. Then, when the corrugated cardboard sheet S is conveyed to the positions of the second printing unit 21B and the fourth printing unit 21D, the second printing unit 21B prints the barcode B2 on the sheet piece 322, and at the same time, the fourth printing unit 21D prints the bar code B4 on the sheet strip 324;

At this time, as shown in FIGS. 4, 5, 8 and 9, the corrugated cardboard sheet S reaches the first printing unit 21A while being attracted to the upper surface of the conveying belt 33 in the first printing unit 21A. Then, the leading end enters the predetermined gap H between the upper surface of the conveyor belt 33 and the lower surface of the driving belt 115 of the driving body 71 . At this time, since the blocking plate 181 is provided on the conveying belt 33 side facing the inkjet head 61, the corrugated cardboard sheet S is sucked from the conveying belt 33 side to the lower surface by the non-suction length region Ls of the blocking plate 181. does not work. However, the corrugated cardboard sheet S is pressed against the upper surface (printing surface) of the drive belt 115 which is driven to rotate. As a result, the corrugated cardboard sheet S, with its lower surface placed on the upper surface of the conveying belt 33, is held down by the upper surface (printing surface) coming into contact with the driving belt 115 that rotates. At this time, the rotational speed (peripheral speed) of the drive belt 115 is the same as or slightly higher than the moving speed (peripheral speed) of the transport belt 33. 115 and stably transported.

Therefore, for example, even if the leading edge of the corrugated cardboard sheet S in the conveying direction T is warped upward, the corrugated cardboard sheet S is pressed by the drive belt 115 that drives and rotates at the warped leading edge to form a flat shape, or , is corrected to a nearly flat shape. Even if the corrugated cardboard sheet S is warped downward, the corrugated cardboard sheet S is pressed by the drive belt 115 that rotates and is corrected to a flat shape or a shape close to a flat shape. The drive belt 115 contacts the printed surface of the corrugated cardboard sheet S at a predetermined length in the conveying direction T and moves along the conveying direction T, so that the corrugated cardboard sheet S buckles. It is stably conveyed while maintaining a flat shape. Then, the distance between the printing surface of the corrugated cardboard sheet S and the inkjet head 61 is maintained at a constant distance, and the inkjet head 61 can print on the printing surface of the corrugated cardboard sheet S with high accuracy.

In addition, since the blocking plate 181 is provided on the conveying belt 33 side facing the inkjet head 61, the suction force from the suction unit 32 does not act on the inkjet head 61, and the inkjet head 61 is in a state of ink. remain stable. Therefore, when the corrugated cardboard sheet S is conveyed to a position facing the inkjet head 61 , the inkjet head 61 can appropriately eject ink onto the printing surface of the corrugated cardboard sheet S. In addition, since the blocking plate 181 is provided in the non-suction length region Ls shorter than the length of the cardboard sheet S, stable conveyance of the cardboard sheet S is not adversely affected.

As described above, in the printing apparatus of this embodiment, the conveying unit 31 conveys the cardboard sheet S while sucking the non-printing surface of the cardboard sheet S with the suction unit 32, and the ink jet heads 61, 62, 63, and 64. A blocking plate 181 (182, 182, 183).

Therefore, the corrugated cardboard sheet S is conveyed while the lower surface is sucked by the suction unit 32, and printing is performed on the printing surface by the inkjet heads 61, 62, 63, and 64. FIG. At this time, since the blocking plate 181 is provided at a position facing the inkjet heads 61, 62, 63, 64, when there is no cardboard sheet S at a position facing the inkjet heads 61, 62, 63, 64, the inkjet head 61 , 62, 63 and 64, the state of the ink is stably maintained and the behavior of the ink is stabilized. Then, when the corrugated cardboard sheet S is transported to a position facing the inkjet heads 61, 62, 63, 64, ink is properly ejected from the inkjet heads 61, 62, 63, 64 onto the printing surface of the corrugated cardboard sheet S. The Rukoto. As a result, the ejection state of ink from the nozzles of the inkjet heads 61, 62, 63, and 64 is stabilized, and the corrugated cardboard sheet S is stably conveyed, thereby suppressing deterioration in printing accuracy.

In the printing apparatus of the present embodiment, the blocking plate 18 is set in a predetermined non-suction state in which the length in the transport direction T of the corrugated cardboard sheet S is longer than the ink ejection length region Lp of the inkjet heads 61 , 62 , 63 , 64 . It is set in the length area Ls. Therefore, since the non-suction length region Ls of the blocking plate 181 is longer than the ink ejection length region Lp of the inkjet heads 61, 62, 63, 64, the ink ejection length region Lp of the inkjet heads 61, 62, 63, 64 , no suction force acts on the inkjet heads 61, 62, 63, 64, and the ink ejection state from the nozzles of the inkjet heads 61, 62, 63, 64 can be stabilized.

In the printing apparatus of the present embodiment, the blocking plate 181 is provided over the entire area in the width direction along which the corrugated cardboard sheet S is conveyed. Therefore, when a plurality of printing units 21A, 21B, 21C, and 21D are arranged in the width direction of the corrugated cardboard sheet S, only one closing plate 181 is required, and the structure can be simplified.

In the printing apparatus of this embodiment, a plurality of blocking plates 182 and 183 are provided in the width direction of the cardboard sheet S corresponding to the plurality of printing units 21A, 21B, 21C and 21D. Therefore, the area of the closing plate 182 becomes smaller than the corrugated cardboard sheet S, and the corrugated cardboard sheet S can be conveyed stably.

The printing apparatus of this embodiment is provided with a non-suction portion movement adjustment device 184 that moves the blocking plates 182 and 183 in the width direction of the cardboard sheet S. As shown in FIG. Therefore, when the printing positions are adjusted by moving the printing units 21A, 21B, 21C, and 21D along the width direction of the corrugated cardboard sheet S, depending on the adjusted positions of the printing units 21A, 21B, 21C, and 21D, the By moving the closing plates 182 and 183 in the width direction of the corrugated cardboard sheet S by means of the suction portion movement adjusting device 184, their positions can be adjusted easily and with high precision.

In the printing apparatus of the present embodiment, the non-suction portions are blocking plates 181 , 182 , and 183 that partially block the suction area of the suction portion 32 . Therefore, simplification of the structure can be achieved.

In the printing apparatus of the present embodiment, as the suction unit 32, a plurality of divided suction units 191 divided in the width direction of the corrugated cardboard sheet S are provided, and the non-suction units are arranged at positions facing the inkjet heads 61, 62, 63, 64. A divided suction portion 191 is provided. Therefore, since the non-suction portion is the divided suction portion 191, the position of the non-suction portion can be easily changed.

In the printing apparatus of this embodiment, the printing units are provided with driving bodies 71, 72, 73, and 74 that are rotatable and can come into contact with the printing surface of the corrugated cardboard sheet S. As shown in FIG. Therefore, when the corrugated cardboard sheet S is conveyed and the printing surface of the corrugated cardboard sheet S is printed by the inkjet heads 61, 62, 63, and 64, the corrugated cardboard sheet S faces the inkjet heads 61, 62, 63, and 64. Although the lower surface of the corrugated cardboard sheet S is not sucked at the position where the corrugated cardboard sheet S is pressed, the printed surface contacts the driving bodies 71, 72, 73, and 74 that are driven to rotate, so the corrugated board sheet S is conveyed by the driving bodies 71, 72, 73, and 74. A conveying force is applied while being pressed against the upper surface of the belt 33 . Therefore, the cardboard sheet S is stably conveyed by the driving bodies 71, 72, 73, and 74, and the inkjet heads 61, 62, 63, and 64 are kept at a constant distance from the printing surface of the cardboard sheet S. can print with high accuracy.

In the printing apparatus of this embodiment, a predetermined constant gap H, which is preset according to the thickness of the corrugated cardboard sheet S, is provided between the upper surface of the conveying belt 33 and the driving members 71, 72, 73, and 74 in the conveying section 31. I have secured. Therefore, when the corrugated cardboard sheet S is conveyed on the upper surface of the conveying belt 33, the corrugated cardboard sheet S enters the fixed gap H secured between the upper surface of the conveying belt 33 and the driving members 71, 72, 73, and 74. , the driving bodies 71, 72, 73, and 74 press the printed surface of the corrugated cardboard sheet S to stably convey it, and the distance between the corrugated cardboard sheet S and the inkjet heads 61, 62, 63, and 64 is kept constant. Then, printing by the inkjet heads 61, 62, 63, 64 can be performed.

In the printing apparatus of this embodiment, a plurality of printing units 21A, 21B, 21C, and 21D are arranged at predetermined intervals in the conveying direction T of the cardboard sheet S. As shown in FIG. Therefore, even if the printing positions of the plurality of printing units 21A, 21B, 21C, and 21D with respect to the printing surface of the corrugated cardboard sheet S are close to the width direction of the corrugated cardboard sheet S, the plurality of printing units 21A, 21B, 21C, and 21D can be Since the printing units 21A, 21C and the printing units 21B, 21D are arranged in the conveying direction of the corrugated cardboard sheet S, they do not interfere with each other. 21D can print at a predetermined position with high accuracy.

In the printing apparatus of this embodiment, a first printing unit 21 having printing units 21A, 21B, 21C, and 21D, and a flexographic printing unit 22A arranged downstream of the first printing unit 21 in the transport direction T of the cardboard sheet S , 22B, 22C, 22D. Therefore, the first printing unit 21 prints on the printed surface of the corrugated cardboard sheet S, and then the second printing unit 22 prints. After that, the time until a member such as a belt comes into contact with the printing surface can be lengthened, and the drying time of the ink in the first printing unit 21 can be secured. Print quality can be improved.

Further, the box making machine of the present embodiment includes a paper feed unit 11 that supplies corrugated cardboard sheets S, a printing unit 12 that prints on the corrugated cardboard sheets S, and a surface of the corrugated cardboard sheets S that is subjected to ruled line processing and grooving. A paper discharge unit 13 for processing, a folder gluer unit 15 for forming a cardboard box B by folding the cardboard sheet S and joining the ends thereof, and after stacking the cardboard boxes B while counting them, are discharged for each predetermined number. and a counter ejector section 16 , and the printing section 12 includes an ink jet first printing section 21 . Therefore, when there is no corrugated cardboard sheet S at a position facing the inkjet heads 61, 62, 63, 64 in the first printing unit 21, the suction force does not act on the inkjet heads 61, 62, 63, 64. The ink state is maintained stably. Then, when the corrugated cardboard sheet S is transported to a position facing the inkjet heads 61, 62, 63, 64, ink is properly ejected from the inkjet heads 61, 62, 63, 64 onto the printing surface of the corrugated cardboard sheet S. The Rukoto. As a result, the ejection state of ink from the nozzles of the inkjet heads 61, 62, 63, and 64 is stabilized, and the corrugated cardboard sheet S is stably conveyed, thereby suppressing deterioration in printing accuracy.

In the above-described embodiment, the first printing section 21 is composed of four printing units 21A, 21B, 21C, and 21D, and the second printing section 22 is composed of four printing units 22A, 22B, 22C, and 22D. However, the number is not limited to one, and may be one or more.

Further, in the above-described embodiment, the corrugated cardboard sheet S is used as the sheet. It can be applied to a printing unit that prints while continuously conveying in .

REFERENCE SIGNS LIST 10 box making machine 11 paper feeding section 12 printing section 13 paper discharging section 14 die cutting section 15 folder gluer section 16 counter ejector section (counter ejector)
21 first printing unit (printing device)
21A, 21B, 21C, 21D printing unit 22 second printing unit 22A, 22B, 22C, 22D printing unit 31 transport unit 32, 190 suction unit 33 transport belt 41, 42, 43, 44 first movement adjustment device 45, 46 2-movement adjustment device 51, 52, 53, 54 support frame 61, 62, 63, 64 inkjet head 71, 72, 73, 74, 161 driver 81, 82 drive device 111 drive roller 112, 113 driven roller 114 idler 115 drive Belts 121, 122 Printer frame 131 Screw shaft 132 Nut 133 Driven gear 134 Drive motor 141 Mounting frame 145 Drive gear 151, 152 Lifting device 153 Lifting frame 154, 155 Lifting support frame 162, 163 Drive roller 164 Drive sprocket 165, 166 Driven Sprocket 167 Idler 168 Chain belt 181, 182, 183 Blocking plate (non-sucking part)
184 non-suction portion movement adjustment device 191 divided suction portion H constant gap S corrugated cardboard sheet (sheet, sheet material for box making)
Wp Ink ejection width area Ws Non-suction width area Lp Ink ejection length area Ls Non-suction length area

Claims (10)

a conveying unit that conveys the sheet while sucking the non-printing surface of the sheet with a suction unit;
a printing unit that prints on the printing surface of the sheet with an inkjet head;
a non-suction portion provided at a position facing the inkjet head in the suction portion;
with
The printing unit has a rotatable drive body capable of contacting the printing surface of the sheet on both sides in the width direction of the ink ejection width region of the inkjet head,
The non-suction portion is set in a predetermined non-suction length region that is longer than the ink ejection length region of the inkjet head in the conveying direction of the sheet,
A printing device characterized by: 2. The printing apparatus according to claim 1 , wherein a predetermined constant gap preset according to the thickness of the sheet is secured between the sheet conveying surface of the conveying unit and the driving member. 2. A plurality of the print units are provided along the width direction of the sheet, and a plurality of the non-suction portions are provided in the width direction of the sheet corresponding to the plurality of the print units. 3. A printing device according to claim 2 . 4. The printing apparatus according to claim 3 , further comprising a non-suction portion movement adjusting device that moves the non-suction portion in the width direction of the sheet. 5. The printing apparatus according to any one of claims 1 to 4 , wherein the non-suction section has a blocking plate that partially blocks the suction area of the suction section. The suction section has a plurality of divided suction sections divided at least in the width direction of the sheet, and the non-suction section is the divided suction section provided at a position facing the inkjet head. The printing device according to any one of claims 1 to 4 . 2. The printing apparatus according to claim 1, wherein the non-suction portion is provided in the entire width direction along which the sheet is conveyed. 8. The printing apparatus according to claim 1, wherein a plurality of said printing units are arranged at predetermined intervals in the conveying direction of said sheet. 9. The printing apparatus according to any one of claims 1 to 8 , wherein a flexographic printing unit is arranged downstream of the printing unit in the direction in which the sheet is conveyed. a paper feed unit for supplying sheet materials for box making;
a printing unit that prints on the box-making sheet material;
a paper discharge unit for performing ruled line processing and grooving processing on the surface of the box-making sheet material;
a folder gluer portion that forms a box by folding the box-making sheet material and joining the ends thereof;
a counter ejector unit that counts and piles up the boxes and then ejects them every predetermined number;
The printing unit has the printing device according to any one of claims 1 to 9 ,
A box making machine characterized by:

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