Sheet feeding mechanism and sheet processing device including the same

Abstract

To provide a technology capable of suppressing the occurrence of idle feeding.SOLUTION: A sheet feeding mechanism 10 includes: a loading part 20 having a loading surface 20a where a sheet bundle S is loaded; an adsorption conveyance mechanism 24 for allowing an adsorption surface 50 to adsorb one piece of sheet of the top of the sheet bundle S on the loading surface 20a and feeding it; and an adjustment mechanism capable of adjusting the inclination of the adsorption surface 50 with respect to the loading surface 20a relatively, according to warping in the case where warping occurs in the sheet bundle S.SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present invention relates to a sheet feeding mechanism and a sheet processing apparatus including the same.

Background Art

[0002] There is known a sheet processing apparatus that stops a sheet by abutting a stopper against the leading end of the conveyed sheet, and in that state, tries to further convey the sheet to bend the sheet, thereby winding the sheet between two folding rollers to fold the sheet.

[0003] When the rigidity of the sheet is high, the sheet does not bend only by trying to further convey the sheet that has stopped abutting against the stopper, and thus the sheet may not be wound between the two folding rollers. Patent Document 1 proposes a sheet processing apparatus including a scoring portion that scores the sheet before abutting the sheet against the stopper, and a folding knife for pushing the sheet between the two folding rollers. According to this sheet processing apparatus, a sheet with relatively high rigidity can also be folded.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] As a result of studying a conventional sheet processing apparatus as described in Patent Document 1, the present inventors have come to recognize the following problems.

[0006] Figures 1(a) and 1(b) illustrate the problems of the prior art. Figures 1(a) and 1(b) show the sheet feeding mechanism 210 of a sheet processing machine. The sheet feeding mechanism 210 comprises a loading section 220 having a loading surface 220a on which sheet bundles are loaded, and a suction transport mechanism 224 that suctions the top sheet of the sheet bundle on the loading surface 220a onto a suction surface 250 and sends it out. The loading surface 220a and the suction surface 250 are substantially parallel. In Figures 1(a) and 1(b), the sheets and thus the sheet bundle S are warped. In Figure 1(a), the sheets and thus the sheet bundle S are warped (curled) convex downwards, that is, both ends are positioned higher towards the ends. In Figure 1(b), the sheets and thus the sheet bundle S are warped convex upwards, that is, both ends are positioned lower towards the ends. In any case, in Figures 1(a) and (b), the sheet is warped, so the sheet and the suction surface 250 are not parallel. If the sheet has low rigidity, its warp is corrected to conform to the suction surface 250, and it is attracted to the suction surface 250. However, if the sheet has high rigidity, its warp is not corrected, and the sheet is not attracted to the suction surface 250. Therefore, a dead feed occurs where the sheet cannot be fed.

[0007] Such problems can occur not only in sheet processing equipment but also in other devices equipped with sheet feeding mechanisms.

[0008] The present invention was made in such circumstances, and one exemplary objective of a certain embodiment is to provide a technology that can suppress the occurrence of sheet misfeed. [Means for solving the problem]

[0009] To solve the above problems, a sheet feeding mechanism according to one aspect of the present invention comprises a loading section having a loading surface on which sheet bundles are loaded, an adsorption transport mechanism that adsorbs the top sheet of the sheet bundle on the loading surface onto an adsorption surface and feeds it out, and an adjustment mechanism that can adjust the relative inclination of the adsorption surface with respect to the loading surface in accordance with the warping of the sheet bundle.

[0010] Another aspect of the present invention is a sheet processing apparatus. This apparatus comprises the sheet feeding mechanism described above and a creasing mechanism for creasing the sheet fed from the sheet feeding mechanism.

[0011] Yet another aspect of the present invention is also a sheet processing apparatus. This apparatus comprises the sheet feeding mechanism described above, and a folding knife that contacts the sheet fed from the sheet feeding mechanism and guides the sheet between a pair of folding rollers.

[0012] Furthermore, any combination of the above components, or any substitution of the components or expressions of the present invention between methods, apparatus, systems, etc., are also valid embodiments of the present invention. [Effects of the Invention]

[0013] According to the present invention, the occurrence of idling can be suppressed. [Brief explanation of the drawing]

[0014] [Figure 1] Figures 1(a) and 1(b) illustrate the challenges of the conventional technology. [Figure 2] This is a cross-sectional view of a sheet processing apparatus according to an embodiment. [Figure 3] Figure 2 is an enlarged cross-sectional view showing the sheet feeding mechanism. [Figure 4] Figure 2 shows the sheet feeding mechanism viewed from the upstream side in the conveying direction. [Figure 5] Figure 2 shows the sheet feeding mechanism viewed from the right side in the width direction. [Figure 6] Figure 2 is a perspective view of the air discharge mechanism from the upstream and top side. [Figure 7] Figures 6(a) to 6(c) illustrate the adjustment of the inclination of the adsorption surface using the adjustment mechanism shown in Figure 3. [Figure 8] Figure 2 is an enlarged cross-sectional view showing the slitting section, folding section, and stacking section in detail. [Figure 9] Figure 8 is an enlarged cross-sectional view showing the folded plate and its surrounding area in the folded section. [Figure 10] This is a diagram for explaining the adjustment of the inclination of the loading surface by the adjustment mechanism according to the modified example.

Embodiments for Carrying out the Invention

[0015] Hereinafter, the present invention will be described with reference to the drawings based on preferred embodiments. The embodiments are illustrative and not restrictive, and all features and combinations thereof described in the embodiments are not necessarily essential to the invention. The same or equivalent components, members, and processes shown in each drawing are denoted by the same reference numerals, and redundant descriptions will be omitted as appropriate.

[0016] (Overall Configuration) Refer to FIG. 2. The sheet processing apparatus 1 is an apparatus for performing predetermined processing such as scoring and folding on a sheet. The sheet targeted by the sheet processing apparatus 1 may be warped depending on the previous processing and environment, etc., and is typically paper. The sheet processing apparatus 1 is particularly preferably used when the rigidity of the sheet is high, for example, when the sheet is cardboard. That is, the sheet feeding mechanism 2 can feed a cardboard sheet without causing an idle feed, and thus can score a cardboard sheet or fold a cardboard sheet. The cardboard here may be paper of 200 g / m 2 .

[0017] Hereinafter, the direction in which the sheet is conveyed (the direction from left to right in FIG. 1) is referred to as the conveyance direction X, and the direction orthogonal to the conveyance direction X (the direction orthogonal to the paper surface in FIG. 1) is referred to as the width direction Y.

[0018] The sheet processing apparatus 1 includes a sheet feeding mechanism 十 for feeding sheets one by one, a scoring unit 12 for scoring the sheets fed one by one, a folding unit 14 for folding the sheet along the scored line, a stacker unit 16 for discharging the scored or folded sheets, and a control unit 18 for comprehensively controlling the sheet processing apparatus 1. The sheet feeding mechanism 10, the scoring unit 12, the folding unit 14, and the stacker unit 16 are arranged in this order from the upstream side (the left side in FIG. 1) in the conveyance direction X.

[0019] (Sheet feeding mechanism) Refer to Figures 3-6. The sheet feeding mechanism 10 includes a loading section 20, a level sensor 22, a suction transport mechanism 24, an adjustment mechanism 26, and a detection section 28.

[0020] The loading section 20 has a flat loading surface 20a. A sheet bundle S is loaded onto the loading surface 20a. The loading section 20 is driven up and down by a drive mechanism (not shown). A level sensor 22 detects when the top sheet of the sheet bundle S on the loading surface 20a is above a predetermined height. The drive mechanism raises the loading section 20 when the number of sheets in the sheet bundle S decreases and the level sensor 22 no longer detects the sheet bundle S, and stops raising the loading section 20 when the level sensor 22 detects the sheet bundle S. As a result, the top sheet of the sheet bundle S is kept at a constant height.

[0021] The detection unit 28 detects when the upper surface of the sheet bundle S pushes up the suction chamber 42. When the upward push of the suction chamber 42 by the sheet bundle S is detected, the upward movement of the loading unit 20 is stopped. This prevents situations where the loading unit 20 continues to rise without stopping, for example due to a malfunction of the level sensor 22, and therefore prevents the loading unit 20 from damaging the suction transport mechanism 24.

[0022] The suction transport mechanism 24 includes a transport mechanism 30, a suction mechanism 32, and an air discharge mechanism 34.

[0023] The conveying mechanism 30 includes an upstream roller 36, a downstream roller 38, and a plurality of feed belts 40 stretched between the upstream roller 36 and the downstream roller 38. The plurality of feed belts 40 are provided at predetermined intervals in the width direction Y. The downstream roller 38 is a driven roller. The downstream roller 38 is rotatably supported by left and right fixed frames 8 (only the left fixed frame 8 is shown in Figure 3). The downstream roller 38 is a driven roller and is connected to a drive motor (not shown) via, for example, a clutch and gears. The upstream roller 36 is a driven roller. When the downstream roller 38 rotates, the feed belts 40 revolve.

[0024] The suction mechanism 32 sucks up the top sheet and attaches it to the suction surface 50 of the conveying mechanism 30. The suction mechanism 32 includes a suction chamber 42 provided inside the multiple supply belts 40, a suction fan 44, and a valve mechanism 46.

[0025] The suction chamber 42 has a plurality of suction ports 42a on the surface facing the loading surface 20a (i.e., the bottom surface). The plurality of suction ports 42a are in particular located in positions that avoid the feed belt 40, that is, in positions that are not blocked by the feed belt 40, specifically between the feed belts 40 and on the outside of the feed belt 40 in the width direction Y.

[0026] The suction port of the suction fan 44 (not shown) communicates with the inside of the suction chamber 42. When the suction fan 44 is operated, it sucks air from inside the suction chamber 42, creating a negative pressure inside the suction chamber 42, which is then drawn in through the multiple suction ports 42a. The suction fan 44 preferably has relatively high performance so that it can suck up the sheet even if the sheet is made of cardboard, i.e., even if it is relatively heavy. For example, it should have a maximum airflow (standard value) of 1.85 m³. 3 The minimum output per minute ( / min) may be greater than or equal to 1950 Pa or greater.

[0027] The suction chamber 42 has an air vent hole 42b (see Figure 4). The valve mechanism 46 includes an opening / closing plate 48 and a solenoid 52 that moves the opening / closing plate 48 up and down to open and close the air vent hole 42b. When the suction fan 44 is drawing in air, lowering the opening / closing plate 48 opens the air vent hole 42b, eliminating negative pressure inside the suction chamber 42 and stopping suction from the suction port 42a. Raising the opening / closing plate 48 closes the air vent hole 42b, creating negative pressure inside the suction chamber 42 and starting suction from the suction port 42a.

[0028] The air discharge mechanism 34 is provided downstream of the loading section 20. The air discharge mechanism 34 discharges air toward the front end of the sheet bundle S loaded on the loading section 20, improving the separation of the top sheet from the second sheet down from the top sheet in the sheet bundle S loaded on the loading section 20. The air discharge mechanism 34 includes a discharge air chamber 54 and a blower fan (not shown). The air outlet of the blower fan is in communication with the inside of the discharge air chamber 54.

[0029] A box-shaped discharge chamber 112 is provided in the upper center of the discharge air chamber 54, with a first air outlet 114 and a second air outlet 116 formed therein. The second air outlet 116 is formed below the first air outlet 114. Air is discharged from the first air outlet 114 diagonally upward, and air is discharged from the second air outlet 116 diagonally downward. The second air outlet 116 can be opened and closed by sliding the shielding plate 118 in the width direction Y. In addition, discharge chambers 120 are provided on both sides of the discharge chamber 112 in the width direction Y at the top of the discharge air chamber 54, with a third air outlet 122 formed therein. Air is discharged horizontally from the third air outlet 122.

[0030] If the width of the sheet in the width direction Y is wider than the width of the suction conveying mechanism 24, both sides of the sheet in the width direction Y may sag. Therefore, if there is a step in the discharge chamber 120, the sheet may get caught on that step. To address this, an inclined surface 120b is provided on the upstream side of the discharge chamber 120, which is smoothly connected to the upper wall 120a of the discharge chamber 120 without any step. This ensures that the sheet is conveyed without getting caught on any steps. In Figure 6, the two discharge chambers 120 each have two inclined surfaces 120b spaced apart in the width direction Y, but they may also have only the inclined surface 120b on the outside in the width direction Y (the side farther from the center in the width direction Y, or in other words, the side farther from the other discharge chamber 120).

[0031] When the air vent hole 42b of the suction mechanism 32 is closed and suction from the multiple suction ports 42a is started, and air for separation is discharged from the air discharge ports 48a and 48b of the air discharge mechanism 34, the uppermost sheet is attracted to the "suction surface 50," which is the outer peripheral surface of the feed belt 40 that is facing downwards and opposite the loading surface 20a. Once the sheet is attracted to the suction surface 50, the feed belt 40 is rotated. This sends the sheet toward the ribbing section 12. When the leading edge of the sheet reaches the pair of conveyor rollers 56, the air vent hole 36c is opened and suction from the multiple suction ports 42a is stopped.

[0032] Refer to Figures 7(a) to 7(c). The adjustment mechanism 26 is a mechanism for adjusting the inclination of the suction surface 50 with respect to the loading surface 20a. The adjustment mechanism 26 adjusts the inclination by moving the suction surface 50. The adjustment mechanism 26 can adjust the inclination of the suction surface 50 with respect to the loading surface 20a to a state where the loading surface 20a and the suction surface 50 are parallel (see Figure 7(a)), a state where the loading surface 20a and the suction surface 50 are further apart downstream (see Figure 7(b)), or a state where they are closer downstream (see Figure 7(c)). For the state where the loading surface 20a and the suction surface 50 are further apart downstream (the state in Figure 7(b)), the adjustment mechanism 26 may be able to adjust the inclination in one or more steps, or it may be possible to adjust the inclination steplessly up to a predetermined angle. Furthermore, the adjustment mechanism 26 may be capable of adjusting the inclination in one or more stages when the loading surface 20a and the suction surface 50 are closer together towards the downstream side (the state shown in Figure 7(c)), or it may be capable of continuously adjusting the inclination up to a predetermined angle.

[0033] The adjustment mechanism 26 may move the suction surface 50 (i.e., the supply belt 40) together with the suction chamber 42 as shown in Figures 7(a) to (c), or it may move the suction surface 50 together with the suction chamber 42 and other components (e.g., valve mechanism 46) which are not shown in Figures 7(a) to (c), or, unlike in Figures 7(a) to (c), it may move the suction surface 50 (i.e., the supply belt 40) without moving the suction chamber 42.

[0034] In Figure 7(a), since the sheet is not warped, the inclination of the suction surface 50 is adjusted so that the loading surface 20a and the suction surface 50 are parallel. In Figure 7(b), the sheet is warped downwards, that is, both ends are positioned higher towards the ends, so the inclination of the suction surface 50 is adjusted so that the loading surface 20a and the suction surface 50 are further apart towards the downstream side. In Figure 7(c), the sheet is warped upwards, that is, both ends are positioned lower towards the ends, so the inclination of the suction surface 50 is adjusted so that the loading surface 20a and the suction surface 50 are closer together towards the downstream side. In Figures 7(b) and 7(c), by adjusting the inclination of the suction surface 50, the sheet and the suction surface 50 are parallel over a wider area compared to when the suction surface 50 is not inclined.

[0035] An example of the specific configuration of the adjustment mechanism 26 will be explained with reference to Figures 4 and 5. The adjustment mechanism 26 includes a movable frame 60, a lever 62, and a click stopper 64. The movable frame 60 rotates around the downstream roller 38. When the movable frame 60 rotates, the members directly or indirectly supported by it, specifically the suction chamber 42, the feed belt 40 (suction surface 50), the valve mechanism 46, and the detection unit 28, also rotate. In other words, the adjustment mechanism 26 moves the suction surface 50 together with the suction chamber 42, and also moves the detection unit 28 together with the suction surface 50. The adjustment mechanism 26 also moves the suction chamber 42 together with the valve mechanism 46. In this case, the configuration becomes relatively simple.

[0036] The lever 62 is fixed to the upper part of the movable frame 60 and rotates integrally with the movable frame 60. The click stopper 64 is fixed to a fixed frame 8 (not shown in Figures 4 and 5). When the user operates the lever 62 and the lower end of the lever 62 engages with one of the teeth of the click stopper 64, the lever 62, and consequently the movable frame 60, and consequently the suction surface 50 are positioned at a rotation angle corresponding to that tooth. For example, the loading surface 20a and the suction surface 50 can be positioned parallel to each other, the loading surface 20a and the suction surface 50 are further apart downstream and the acute angle between them is 2° or 4°, and the loading surface 20a and the suction surface 50 are closer downstream and the acute angle between them is 2° or 4°. Regardless of the position, the guide inclinations 70 and 72 (see Figure 2) guide the material to the grooved section 12.

[0037] (Muscle formation area) Refer to Figure 8. The grooving section 12 comprises a pair of upstream rollers 74, a pair of downstream rollers 76, a blade 78, a receiving section 80, and a sensor 82.

[0038] Sensor 82 is located downstream of the upstream roller 74. The upstream roller 74 and the downstream roller 76 are driven by a main motor (not shown). The main motor is equipped with an encoder. For example, when the leading edge of the sheet is detected by sensor 82, the pulse from the encoder is counted, and the sheet is stopped so that the position where the fold should be made is directly below the blade 78. The blade 78 is lowered to make the fold. If a tri-fold or double-fold is to be performed, two folds are made. The drive of the upstream roller 74 and the downstream roller 76 is restarted to send the sheet to the folding section 14.

[0039] (Folded section) Refer to Figure 8. The folding section 14 includes a transport roller 84, a first folding roller 86, a second folding roller 88, a third folding roller 90, a first folding knife 92, a second folding knife 94, and a pair of transport rollers 96.

[0040] Each roller 84, 86, 88, 90, and 96 of the folding section 14 is driven by the main motor. In other words, it is driven by the same drive source as each roller 74 and 76 of the creasing section 12. Therefore, while each roller 74 and 76 of the creasing section 12 is stopped, each roller 84, 86, 88, 90, and 96 of the folding section 14 is also stopped.

[0041] The sheet fed into the folding section 14 is transported in the direction of arrow A by the transport roller 84, the first folding roller 86, and the pair of transport rollers 96. If the sheet is not folded (only creases are made), the sheet is discharged as is to the second stacker section 104 of the stacker section 16. The pair of transport rollers 96 can move toward and away from each other, and when folding the sheet as described later, the pair of transport rollers 96 are moved apart from each other.

[0042] When folding the sheet in half, pulses from the encoder are counted, and before the leading edge of the sheet reaches the folding section 14, for example, before it reaches the space between the transport roller 84 and the first folding roller 86, the first folding knife 92 is moved towards the top dead center (i.e., towards the space between the first folding roller 86 and the second folding roller 88). The sheet is guided between the first folding roller 86 and the second folding roller 88 by the guide surface 92a of the first folding knife 92 and enters between the two guide plates 68a and 68b of the folding plate 68. Pulses from the encoder are counted, and at the timing when the crease made by the creasing section 12 is reached, each roller 84, 86, 88, 90, 96 is stopped, and the second folding knife 94 is advanced (moved) in the direction toward the space between the second folding roller 88 and the third folding roller 90. The moment the second folding knife 94 contacts the sheet, or slightly before or after that moment, the drive of each roller 84, 86, 88, 90, 96 is restarted, and the sheet is moved between the two folding rollers. The sheet is wrapped between the second folding roller 88 and the third folding roller 90, folded along the crease, and discharged with the fold leading.

[0043] When folding the sheet into thirds or in an open gatefold, pulses from the encoder are counted, and when the crease made by the creasing unit 12 is reached, each roller 84, 86, 88, 90, 96 is stopped, and the first folding knife 92 is raised in the direction toward the space between the first folding roller 86 and the second folding roller 88. At the moment the first folding knife 92 contacts the sheet, or slightly before or after that moment, the driving of each roller 84, 86, 88, 90, 96 is restarted, and the sheet is moved between the two folding rollers. The sheet is wrapped between the first folding roller 86 and the second folding roller 88, folded along the crease, and enters between the two guide plates 68a and 68b of the folding plate 68 with the crease leading.

[0044] Furthermore, pulses from the encoder are counted, and when another crease made by the creasing unit 12 arrives, each roller 84, 86, 88, 90, 96 is stopped, and the second folding knife 94 is advanced (moved) in the direction between the second folding roller 88 and the third folding roller 90. The moment the second folding knife 94 contacts the sheet, or slightly before or after that moment, the driving of each roller 84, 86, 88, 90, 96 is restarted, and the sheet is moved between the two folding rollers. The sheet is wrapped between the second folding roller 88 and the third folding roller 90, folded along the crease, and discharged with the crease leading.

[0045] The timing for stopping rollers 84, 86, 88, 90, and 96 is, for example, the timing when the crease made by the creasing unit 12 stops at the position where the tip of the advancing first folding knife 92 or second folding knife 94 makes contact. Alternatively, for example, the timing may be when the crease made by the creasing unit 12 stops at a position slightly upstream or downstream of the position where the tip of the advancing first folding knife 92 or second folding knife 94 makes contact. Specifically, experiments are conducted to determine the appropriate timing for stopping rollers 84, 86, 88, 90, and 96 by ensuring that the position in the transport direction X of the crease formed by the first folding roller 86 and the second folding roller 88, or the second folding roller 88 and the third folding roller 90, matches the position in the transport direction X of the crease made by the creasing unit 12. If the relative positions of the folds and creases change depending on the quality and thickness of the sheet, the timing for stopping rollers 84, 86, 88, 90, and 96 may be predetermined based on the quality and thickness of the sheet, obtained from operator input, sensors, communication lines, etc.

[0046] Guide plates 75 and 77 are provided between the sensor 82 and the slitting section 12, and guide plates 79, 81, and 83 are provided between the slitting section 12 and the rollers 84 and 86, respectively, to guide the front and back surfaces of the conveyed sheet. When the sheet passes the sensor 82, it is conveyed between guide plate 75 and guide plate 77. When the sheet further passes the slitting section 12, it passes between guide plates 79, 81 and guide plate 83. Guide plates are provided to guide the front and back surfaces of the sheet along almost its entire length, excluding the slitting section 12, from when the sheet passes the sensor 82 until it is sandwiched between the rollers 84 and 86. Furthermore, the gap in the thickness direction between the upper guide plates 75, 79, and 81 and the lower guide plates 77 and 83 is relatively narrow to suppress warping in the thickness direction of the passing sheet. Specifically, it is about 1.5 to 2.5 mm. Furthermore, the angle θ of the tangent to the outer surface of the outer surface of the outer surface of the outer surface of the outer surface of the lower roller of the upstream roller 74 with respect to the horizontal plane at the point where it intersects with the upper surface of the guide plate 77 is set to approximately 12-16°. This prevents excessive resistance when the leading edge of the conveyed sheet collides with the lower roller, allowing it to pass through smoothly. The same applies to the angle of the tangent to the outer surface of the outer surface of the lower roller of the downstream roller 76 at the point where it intersects with the upper surface of the guide plate 83. These configurations suppress warping of the sheet as it passes through the guide plates 75, 77, 79, 81, and 83, and allow for smooth conveyance. As a result, the relationship between the number of pulses counted after the leading edge of the sheet passes through the sensor 82 and the actual amount of sheet conveyed becomes stable. Consequently, the creases created by the creasing section 12 and the folds created by the creasing rollers 86, 88, and 90 can be precisely aligned in the conveyance direction X.

[0047] The extension amount of at least one of the first folding knife 92 and the second folding knife 94 may be adjustable. When the sheet is thin and therefore has low rigidity, the direction of the tip is not stable, so the extension amount of the folding knife is increased to ensure that the sheet is reliably guided to the nip of the folding roller. When the sheet is thick and therefore has high rigidity, the sheet is closer to the folding knife due to its thickness and does not conform well to the outer surface of the folding roller, so it is prone to friction and scratching with the tip of the folding knife. For this reason, the extension amount of the folding knife is reduced. For example, an extension amount adjustment mechanism (not shown) may be provided, which includes a rotating shaft, a drive motor that rotates the rotating shaft, and a conversion mechanism that converts the rotation of the rotating shaft into linear motion of the folding knife, and the extension amount of the folding knife may be managed by acquiring the amount of rotation of the motor shaft of the drive motor or the rotating shaft with an encoder.

[0048] Refer to Figure 9. The position of the guide plate 68b may be switchable between a first position where its lower end is located at the first lower end position H1 and a second position where its lower end is located at the second lower end position H2, which is lower than the first lower end position H1 (i.e., closer to the second folding roller 88 and the third folding roller 90).

[0049] If the sheet S1 is thick and therefore has high rigidity, the sheet S1 is difficult to bend. If the lower end of the guide plate 68b is at the second lower end position H2, the sheet S1 will not be able to bend completely from between the two guide plates 68a and 68b towards the second folding roller 88 and the third folding roller 90, causing it to get stuck and jam. Therefore, if the sheet S1 is thick, the guide plate 68b should be positioned at the first position.

[0050] If the sheet S1 is thin and therefore has low rigidity, and the lower end of the guide plate 68b is at the first lower end position H1, the tip E of S1 that passes between the first folding roller 86 and the second folding roller 88 will not be caught between the guide plates 68a and 68b, making it unstable and causing double folding or wrinkles. Therefore, if the sheet S1 is thin, the guide plate 68b should be positioned at the second position.

[0051] (Stacker section) Refer to Figure 8. The stacker section 16 comprises a first stacker section 102 and a second stacker section 104. The second stacker section 104 is located below the first stacker section 102. The first stacker section 102 includes a stacker plate 106, a belt 108 that is intermittently driven on the stacker plate 106, and rollers 110 that roll on the belt 108. Sheets coming out from between the second folding roller 88 and the third folding roller 90 are discharged onto the intermittently driven belt 108 of the first stacker section 102 and pressed down by the rollers 110 to be stacked in a half-overlapping state. Sheets that are not folded (only creased) are discharged to the second stacker section 104.

[0052] (Control Unit) The control unit 18 includes a CPU that performs various calculations, a ROM that stores various control programs, and RAM which is used as a work area for data storage and program execution. The control unit 18 controls the operation of actuators such as motors that drive each mechanism.

[0053] According to the embodiment described above, if the sheet is warped, the inclination of the suction surface 50 with respect to the loading surface 20a can be adjusted according to the direction and degree of the warping. As a result, even if a highly rigid sheet is warped, the sheet can be adsorbed onto the suction surface 50, thereby suppressing the occurrence of empty feeds.

[0054] The present invention has been described above based on embodiments. These embodiments are illustrative, and it will be understood by those skilled in the art that various modifications are possible in combinations of these components and processing processes, and that such modifications also fall within the scope of the present invention. Such modifications will be described below.

[0055] (Variation 1) In the embodiment described, the inclination of the suction surface 50 relative to the loading surface 20a was adjusted by moving (tilting) the suction surface 50. However, the embodiment is not limited to this, and the inclination of the suction surface 50 relative to the loading surface 20a may also be adjusted by moving (tilting) the loading surface 20a, i.e., the loading section 20.

[0056] Refer to Figure 10. The upstream end of the loading section (plate) 20 is rotatably supported by a support shaft 21 extending in the width direction Y. The downstream end of the loading section 20 is moved up and down, for example by a cam 23. This allows adjustment of the inclination of the loading surface 20a relative to the suction surface 59. Alternatively, the downstream end of the loading section 20 may be supported by the support shaft 21, and the upstream end of the loading section 20 may be moved up and down. This modified example can achieve the same effects as the embodiment.

[0057] (Modification 2) Unlike the embodiment and the modifications described above, the inclination of the suction surface 50 with respect to the loading surface 20a may be adjustable only to the extent that the loading surface 20a and the suction surface 50 are further apart on the downstream side (i.e., it may not be adjustable to the extent that they are closer together on the downstream side). In this case, the sheet bundle that is warped should be loaded onto the loading surface 20a so that the warp faces upward.

[0058] Furthermore, unlike the embodiment and the modifications described above, the inclination of the suction surface 50 with respect to the loading surface 20a may be adjustable only to a state where the loading surface 20a and the suction surface 50 are closer together as the downstream side approaches (i.e., it may not be adjustable to a state where they are further apart as the downstream side approaches). In this case, the sheet bundle that is warped should be loaded onto the loading surface 20a so that the warp faces downwards.

[0059] (Variation 3) Unlike the embodiment, for example, a camera or appropriate sensors may be provided to identify the direction and degree of curvature of the sheet bundle S on the loading surface 20a, and the adjustment mechanism 26 may be configured to include a drive source such as a motor, and the adjustment mechanism 26 may automatically adjust the inclination of the suction surface 50 relative to the loading surface 20a according to the identified direction and degree of curvature. In this case, the burden on the user is reduced.

[0060] Any combination of the embodiments and modifications described above is also useful as an embodiment of the present invention. The new embodiments resulting from these combinations possess the combined effects of the respective embodiments and modifications. Furthermore, it will be understood by those skilled in the art that the functions to be performed by each component described in the claims can be achieved by each component shown in the examples and modifications individually or in combination thereof. [Explanation of symbols]

[0061] 1 Sheet processing device, 10 Sheet feeding mechanism, 12 Scoring section, 14 Folding section, 20 Loading section, 20a Loading surface, 24 Suction transport mechanism, 26 Adjustment mechanism, 28 Detection section, 32 Suction mechanism, 42 Suction chamber, 42a Suction port, 46 Valve mechanism, 50 Suction surface.

Claims

1. A loading section having a loading surface on which sheet bundles are stacked, A suction transport mechanism that suctions the top sheet of the sheet bundle on the loading surface onto the suction surface and sends it out, An adjustment mechanism that can adjust the relative inclination of the suction surface with respect to the loading surface in accordance with the warping of the sheet bundle, A sheet feeding mechanism equipped with this.

2. The sheet feeding mechanism according to claim 1, wherein the adjustment mechanism is capable of adjusting the inclination between a state in which the loading surface and the suction surface are parallel, and a state in which the loading surface and the suction surface are further apart or closer together as they move downstream.

3. The sheet feeding mechanism according to claim 1, wherein the adjustment mechanism is capable of adjusting the inclination in multiple stages or steplessly.

4. The sheet feeding mechanism according to claim 1, wherein the adjustment mechanism adjusts the inclination by moving the suction surface.

5. The adsorption transport mechanism includes a suction mechanism for sucking up the sheet and adsorbing the sheet onto the adsorption surface, The suction mechanism includes a suction chamber having a suction port on the surface facing the loading surface, a suction fan communicating with the suction chamber, and a valve mechanism capable of releasing the negative pressure inside the suction chamber. The sheet feeding mechanism according to claim 4, wherein the adjustment mechanism moves the suction surface together with the suction chamber.

6. The sheet feeding mechanism according to claim 5, wherein the adjustment mechanism moves the suction chamber together with the valve mechanism.

7. The suction transport mechanism includes a detection unit that detects when it is pushed up onto the sheet bundle on the loading surface, The sheet feeding mechanism according to claim 4, wherein the adjustment mechanism moves the detection unit together with the suction surface.

8. The sheet feeding mechanism according to claim 1, wherein the adjustment mechanism has an operating part that allows the user to adjust the inclination of the suction surface with respect to the loading surface.

9. The sheet feeding mechanism according to claim 1, wherein the adjustment mechanism includes a drive source for adjusting the inclination of the suction surface with respect to the loading surface.

10. comprising a means for identifying the direction and degree of curvature of the sheet bundle on the loading surface, The sheet feeding mechanism according to claim 9, wherein the adjustment mechanism automatically adjusts the inclination of the suction surface 50 with respect to the loading surface according to the direction and degree of warping identified by the specific means.

11. A sheet feeding mechanism according to any one of claims 1 to 10, A creasing unit that makes creases in the sheet fed from the sheet feeding mechanism, A sheet processing device equipped with the following features.

12. A sheet feeding mechanism according to any one of claims 1 to 10, A folding knife that contacts the sheet fed from the sheet feeding mechanism and guides the sheet between a pair of folding rollers, A sheet processing device equipped with the following features.

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