JP2018095336A - Sheet bundle cutting device and sheet bundle holding device, and bookbinding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet cutting device capable of performing high-speed efficient trimming in which a sheet bundle has no position shift inside and may not have any damage, such as a holding trace, left when held, rotated, and positioned at a cutting position to be cut.SOLUTION: A sheet bundle holding part which holds and then rotates a sheet bundle by a predetermined angle and cuts the sheet bundle at a cutting position, selects and sets holding force for holding the sheet bundle and an average rotating speed or maximum rotating speed of the sheet bundle from a plurality of different stages, and holding force or a rotating speed, at which neither a position shift nor damage is caused upon the basis of density of sheets constituting the sheet bundle.SELECTED DRAWING: Figure 8

Description

  The present invention relates to a sheet bundle cutting apparatus, a sheet bundle holding apparatus, and a bookbinding apparatus, and more particularly to a sheet bundle cutting apparatus that cuts the peripheral edge of sheets stacked in a bundle shape, and is rotated in a cutting position by being rotated after the sheet bundle is sandwiched. The present invention relates to a cutting method for cutting.

  In general, a sheet bundle cutting device that trims and cuts the periphery of a sheet bundle that has been bound is known. For example, Japanese Patent Application Laid-Open No. H10-228561 discloses an apparatus that binds and stacks sheets carried out from an image forming apparatus, applies an adhesive, and binds and binds the sheets with a cover sheet bundle. In such a bookbinding apparatus, a sheet bundle cutting apparatus that cuts and aligns the edges in the three directions (the top portion, the ground portion, and the fore edge portion; the same applies hereinafter) of the sheet bundle after bookbinding is used.

  These sheet bundle cutting devices rotate a pair of sandwiching members that sandwich the front cover surface and the back cover surface of a sheet bundle with a driving unit such as a motor, so that the top portion, the ground portion, and the fore edge portion of the sandwiched sheet bundle are separated. Cutting in order. At this time, for example, in the sheet bundle cutting apparatus disclosed in Patent Document 1, the rotation speed is varied depending on the sheet characteristics (size, basis weight, waist strength, friction coefficient) of the cover used for the sheet bundle, and the sheet The sheet bundle is prevented from being damaged or misaligned due to the torque applied to the bundle during the rotation of the bundle and the moment of inertia around the rotation axis.

Japanese Patent Laying-Open No. 2015-150644

  However, in the conventional sheet bundle cutting apparatus described above, there is a possibility that the sheet may be damaged or the position of the cutting position may be shifted depending on the characteristics of the sheet.

  The present invention has been made in view of the problems existing in such a conventional technique, and provides a sheet bundle clamping device, a sheet bundle cutting device, and a bookbinding device that are capable of appropriate clamping according to a sheet bundle. It is in.

  In order to achieve the above object, the present invention has the following configuration.

Clamping means for clamping the sheet bundle with a predetermined clamping force;
And a control unit that changes the predetermined holding force according to the sheets constituting the sheet bundle held by the holding means.

  According to the present invention, appropriate clamping according to the sheet bundle can be performed.

1 is an explanatory diagram of an overall configuration of an image forming system according to the present invention. FIG. 3 is an explanatory diagram of a main configuration of a sheet bundle cutting mechanism (trimmer unit) in the apparatus of FIG. 1. Explanatory drawing which shows the cutting procedure of the trimmer unit of FIG. (A) is a state where the sheet bundle is positioned at the cutting position, (b) is a state where the positioned sheet bundle is clamped, (c) is a state where the sheet bundle is turned to set the cutting position at the cutting position, and (d) is A state in which the edge of the sheet bundle is cut is shown. FIG. 2 shows a state in which the sheet bundle is rotated for cutting in the trimmer unit of FIG. 2, (a) is a schematic view from the front showing that a deviation occurs in the sheet bundle by rotation, and (b) is a sheet bundle by rotation. It is explanatory drawing of the inertia moment which arises. FIG. 2 shows a state in which a sheet bundle is clamped for cutting in the trimmer unit of FIG. 2, (a) is a schematic view from the front showing that grip marks are generated in the sheet bundle by clamping, and (b) is a low-density sheet. Schematic showing the direction of the force applied to the sheet bundle when nipped, (c) is a schematic diagram showing the direction of the force applied to the sheet bundle when nipping high density paper. An example of the table data which shows the relationship between the density of paper, pinching force, and rotational speed. The block diagram which shows the structure of the control part based on the apparatus of FIG. The flowchart which shows the state of the cutting operation in the control structure of FIG.

<First Embodiment>
The present invention will be described in detail below based on the preferred embodiments shown in the drawings. FIG. 1 is an explanatory view of the overall configuration of a bookbinding apparatus according to the present invention, and FIG. 2 is a detailed explanatory view of the bookbinding apparatus.

[Sheet bundle cutting mechanism]
First, the main part mechanism of a sheet bundle cutting apparatus (or sheet cutting apparatus) 1001 which is a sheet processing apparatus according to the present invention will be described with reference to FIG. FIG. 1 shows a configuration of a bookbinding apparatus 1002, and FIG. 2 shows a main configuration of a sheet bundle cutting unit (hereinafter referred to as "trimmer unit") built in the bookbinding apparatus. First, the trimmer unit will be described, and then the bookbinding apparatus 1002 will be described.

  In FIG. 2, the trimmer unit includes a sheet bundle rotating unit 10 such as a turntable that holds and rotates the sheet bundle, a drive unit 13 (such as a motor) that rotates the sheet bundle rotating unit in a predetermined direction, and a cutting position Cp. A cutting edge press unit 17 (pressure mechanism) that holds the sheet bundle, a cutting unit (cutter mechanism) 20 that is arranged at the cutting position Cp and cuts the sheet bundle, and a feeder 25 that sends the sheet bundle to the cutting position. Have Since the sheet bundle rotating unit 10 has a function of holding a sheet bundle, it is also referred to as a sheet bundle holding unit 10.

  The sheet bundle holding unit 10 includes a rotating member, a grip member, a turntable, and the like that grip (pinch) the sheet bundle from the front and back and hold the sheet bundle rotatably. The sheet bundle holding unit 10 rotates the sheet bundle on the upstream side of the cutting position Cp so that the cutting edge faces the cutting position Cp. The sheet bundle holding unit 10 shown in FIG. 2 includes a pair of grip members, a first rotating member (hereinafter referred to as a first grip member) 10a and a second rotating member (hereinafter referred to as a second grip member) 10b. A bearing is rotatably supported by the frame 15. The first grip member 10a is supported so as to be movable in the direction (nip direction) of the sheet bundle (sliding pressure direction) (to the slider bree), and the grip motor Mg releases the nip and nip with the second grip member 10b. It is configured as follows.

  A first rotation motor Mt1 is connected to the first grip member 10a, and a second rotation motor Mt2 is connected to the second grip member 10b. The two motors are connected to each other at the same rotation speed in opposite directions (for example, if one is clockwise, the other Is configured to rotate each grip member. The unit frame 15 is configured to be movable toward the cutting position Cp in a state where the first and second grip members 10a and 10b are mounted, and cuts the sheet bundle gripped by the feed motor Mf and the rack and pinion mechanism. Transfer in the direction of the position Cp.

  The cutting edge press unit 17 holds the sheet bundle sent to the cutting position Cp by the sheet bundle holding unit 10 so that the sheet bundle can be cut. The cutting edge press unit 17 includes a pressurizing member 19, a biasing spring (not shown) that biases the pressurizing member 19, and a pressurizing release member (such as a pulling member and a screw screw member).

  The cutting unit 20 includes a cutting blade 22 and a cutter driving member. The illustrated one includes a plate-shaped cutting blade 22, a cutter operating member (screw mechanism) 23, and a drive motor (cutter motor) Mc. The blade receiving member 21 is disposed at a position facing the cutting blade 22 with the sheet bundle sandwiched between the cutting positions Cp, and is configured by an elastic member that does not wear the cutting edge of the cutting blade 22.

  The feeder unit 25 is configured so that the sheet bundle whose posture is deflected toward the cutting position Cp by the sheet bundle holding unit 10 is fed to the cutting position Cp, or the cutting blade 22 is made to coincide with the cutting line of the sheet bundle. It is configured with any of the moving cutter moving mechanisms. In FIG. 2, as will be described later, the sheet bundle is rotated by the sheet bundle holding unit 10 and deflected in the posture, and then the bundle is moved in the cutting position direction so that the cutting line of the sheet bundle coincides with the cutting blade 22.

  In such a configuration, an outline of how the control unit 55 (described later with reference to FIG. 7) controls the sheet bundle holding unit 10, the cutting edge press unit 17, and the cutting unit 20 will be described with reference to FIG. To do. The sheet bundle holding unit 10 once receives the sheet bundle S sent from the upstream side with the cutting blade 22 directed to the blade receiving member 21 (FIG. 3A), drives the grip motor Mg, and the first grip Nipping is performed between the member 10a and the second grip member 10b (FIG. 3B). The control unit 55 can determine that the sheet bundle has reached a predetermined clamping position of the trimmer unit by conveying the sheet bundle after detecting the sheet bundle with a sensor provided on the conveyance path, for example. Further, the control unit 55 stops the motor Mg in response to a grip signal from a grip sensor (for example, a sheet contact sensor disposed on the first grip member 10a). In this state, the sheet bundle is sandwiched between the first and second grip members 10a and 10b.

  Next, the control unit 55 rotates the first rotary motor Mt1 and the second rotary motor Mt2 at the same speed in opposite directions in this example (FIG. 3C). The illustrated motors Mt1 and Mt2 are stepping motors, and are configured to be able to control the rotation angle (for example, PWM control). Further, the rotational speeds of the motors Mt1 and Mt2 can be adjusted from a high speed to a low speed by the duty ratio of the pulse power supply supplied to the motor driver. The rotation direction of each motor may be determined so that each motor gives torque in the same rotation direction to the sandwiched sheet bundle, either in the same direction or in the opposite direction depending on the arrangement of the motor and the speed reduction mechanism. It can be.

  When the sheet bundle is rotated so that the side to be cut moves to the cutting position and the sheet bundle is moved so that the line to be cut is the cutting position by the cutting blade 22, cutting is performed by the cutting blade 22 (FIG. 3 ( d)).

[Sheet bundle misalignment]
When the control unit 55 drives the motors Mt1 and Mt2 to rotate the sheet bundle sandwiched between the first grip member 10a and the second grip member 10b, a positional deviation occurs in the sheet bundle S. This state will be described with reference to FIG. The sheet bundle S is sandwiched from the front and back by the rotating member (grip member) 10 and rotated by a predetermined angle (for example, 90 degrees, 180 degrees, 270 degrees, etc.) at the rotational speed Rs around the center Lo of the rotating member 10. Here, the center Lo is preferably near the center of gravity of the sheet bundle.

  When the sheet is rotated, a deviation as shown in FIG. 4A may occur in the sheet bundle held by the rotating member 10. This is called positional misalignment. The positional shift is a phase shift between the sheets around the rotation axis if the rotation center Lo coincides with the center of gravity of the sheet bundle. FIG. 4A shows this example. On the other hand, if the rotation center Lo does not coincide with the center of gravity of the sheet bundle, in addition to the phase shift, the parallel movement component also shifts. The cause of the positional deviation of the sheet bundle S is considered to be due to the influence of the moment of inertia acting on the sheet bundle (or the apparent force generated by the moment of inertia). The sheet bundle S is rotated by the grip members 10a and 10b and rotated by a predetermined angle, and then the grip member is stopped. Then, as shown in FIG. 4B, the moment of inertia acts on Lo as shown. The maximum inertia moment Imax acts in the diagonal direction of the center Lo, the inertia moment Imidle acts in the long side direction (left and right direction in the drawing) intersecting at the center Lo, and the inertia moment Imin acts in the short side direction (up and down direction in the drawing). Due to this difference in moment, a positional deviation occurs in the sheet bundle.

  Thus, as shown in FIG. 4B, the moment of inertia acts because the moment of inertia is different in the diagonal direction far from the rotation center Lo (center of the grip member) located at the center of the seat and the short side direction near the rotation center. During this time, a force [= (Imax, Imin) difference] for bending the sheet is generated. At this time, when the frictional force between the sheets forming the layers in the sheet bundle is superior to the bending force, the sheet bundle is not displaced. When the frictional force between the sheets forming a layer in the sheet bundle is weaker than the force (moment) that bends the sheet bundle by rotation, the sheet bundle collapses and misalignment occurs. Even when the sheets constituting the sheet bundle are considered as rigid bodies, that is, when the sheet bending force is not particularly considered, for example, the holding force of the sheet bundle by the rotating member 10 is relatively small, and the friction between the sheets If the force is small enough to prevent the rotation of the sheet due to the moment of inertia, the sheet can be misaligned.

  From the above, the following two solutions can be considered in order to suppress the occurrence of positional deviation of the sheet bundle. One is a method of, for example, slowing the rotational speed of the sheet bundle in order to suppress the moment applied to the sheet bundle. If the rotation speed is slowed down and the time from the stationary state to the steady rotation and the time from the stationary rotation to the stop are not changed, the absolute value of each angular acceleration can be reduced and the moment exerted on the sheet bundle The absolute value of can also be reduced. Even if the angular acceleration is not reduced, the acceleration period (or the deceleration period) is shortened by reducing the rotation speed, and the deviation amount is suppressed. The other is a method of holding the sheet bundle with a large holding force in order to hold the sheet bundle with a holding force higher than the moment applied to the sheet bundle. Here, the holding force higher than the moment refers to a holding force that does not cause a displacement between sheets by generating a frictional force that resists even if a moment acts on the sheet bundle.

  However, when the rotation speed of the sheet bundle is slowed down, the time required for trimming becomes longer than other operations (for example, bookbinding and binding operation), and the processing efficiency of the system decreases. On the other hand, if the clamping force when clamping the sheet bundle is increased, the pressure applied to the clamping position of the sheet bundle and the vicinity thereof increases, which may cause damage to the sheet bundle such as grip marks. . Therefore, depending on the property of the sheet bundle to be sandwiched, both are selectively used. When it is not necessary to slow down the rotational speed, the clamping force is increased. When the clamping force cannot be increased, the rotational speed is decreased. Suppress deviation.

  Here, the mechanism of the occurrence of damage to the sheet bundle will be described. The control unit 55 sandwiches a predetermined position of the sheet bundle S from the front and back sides between the first grip member 10a and the second grip member 10b. Then, damage (grip marks) as shown in FIG. 5A may occur at the position of the sheet bundle held between the grip members. The cause of the damage to the sheet bundle is considered to be the influence of the pressure acting on the sheet bundle. When the sheet bundle S is sandwiched between the grip members 10a and 10b, a pressure N as shown in FIG. 5B acts on the sheet bundle. At this time, as shown in FIG. 5B, when there are a lot of voids in the sheet (the density of the sheet is low), the sheet is easily bent, and the fibers of the paper are bent and remain as traces (FIG. 5). (D)). In other words, a sheet having a higher density and less voids has higher strength and is less likely to be damaged, and a sheet having lower density and more voids has lower strength and is more likely to be damaged. On the other hand, as shown in FIG. 5C, in the case of a high-density sheet, the sheet is difficult to bend and damage is less likely to occur (FIG. 5E).

  Further, the density, which is an index indicating sheet characteristics, affects the smoothness (≈friction coefficient) in addition to the sheet strength. Generally, when the density of a sheet is high, it is known that the smoothness is high (the coefficient of friction is small). From the above, it can be seen that the higher density paper is more resistant to damage and easier to be displaced, and the lower density sheet is less susceptible to damage and difficult to be misaligned.

  Therefore, when the sheet bundle is composed of high-density sheets according to the density of the sheets constituting the sheet bundle that engages the control unit 55 with the first and second grip members 10a and 10b, the grip member Is set to be strong, and the sheet stack is clamped with a large force to suppress misalignment. For sheet bundles composed of low-density sheets, the gripping force by the grip member is weakened compared to the pinching force for the high-density sheet, and the insufficient holding force due to the weakening of the pinching force It is configured so as to suppress the positional deviation by slowing down.

  For this reason, the control unit 55 can select the stop position of the first grip member 10a of the sheet bundle holding unit 10 (the driving amount until the motor Mg is stopped by a signal from the grip sensor) in one of a plurality of different stages. In addition, the rotational speed (average rotational speed or maximum rotational speed) of the sheet bundle holding unit 10 can be selected in one of a plurality of different stages. In the illustrated apparatus, the first rotary motor Mt1 and the second rotary motor Mt2 that rotate the first and second grip members 10a and 10b are formed of stepping motors, and the control unit 55 performs, for example, PWM control so that the grip members 10a and 10b are controlled. The rotation speed of the can be changed.

  In the following, for ease of explanation, a description will be given of a case where the rotational speed is set to a high speed / low speed and the pinching force is controlled to be large / medium / small. It has been explained that the sheet density affects the positional deviation and damage of the sheet bundle.

FIG. 6 shows the density at which the rotation speed at which the positional deviation occurs is set to high speed / low speed at high / low speed while the pinching force at the boundary where damage occurs is large, during the pinching force is small, and low (for example, 1.0 g / cm ³ or more), medium density (for example, 0.8 g / cm ^{3 to} 0.9 g / cm ³ ), and low density (for example, 0.7 g / cm ³ or less). The pinching force and density do not cause damage when a sheet with density Zx is pinched with pinching force Nx, but a sheet with density smaller than Zx is pinched with pinching force Nx, or the pinching force of a sheet with density Zx When N is larger than Nx, the critical value is set to cause damage to the sheet bundle. Similarly, the relationship between the rotational speed and the density is set. In addition, for example, when the sheet having the density Zx is sandwiched with an appropriate clamping force Nx and rotated at the speed Vx, no positional deviation occurs. However, when the sheet is rotated at a speed higher than the speed Vx, a positional deviation occurs (or a threshold value). The value is such that the above positional deviation occurs), and is set at or near the upper limit.

The density of each sheet constituting the sheet bundle to be sandwiched is detected by the detection unit on the upstream side of the trimmer unit, or the operator inputs the density from the input unit 52. Alternatively, it may be obtained from job information received from a computer or the like. The sheet density is calculated from the thickness (mm) and basis weight (g / m ² ) of each sheet as density (g / cm ³ ) = basis weight (g / cm ² ) ÷ thickness (mm) × 1000. May be. In addition, about the density of a sheet | seat, it comprises so that it may discriminate | determine for at least one of the sheets which comprise a sheet bundle. When discriminating a plurality of sheets, the worst case may be used, or the sum of single sheets may be used. In order to obtain the density of the sheet by the density detection unit, for example, a method of detecting the thickness of the sheet with an infrared thickness sensor and obtaining from the above-described weighing based on the above-described formula can be considered. Alternatively, a method of determining a sheet type (plain paper, cardboard, coated paper, etc.) based on light diffusion, reflection, polarization characteristics, etc., and obtaining a standard density previously associated with the determined paper type, etc. Conceivable.

  The correspondence table of the clamping force setting value, the rotation speed and the sheet density shown in FIG. 6 is stored in the storage unit (RAM) 56 as a data table. When executing the cutting operation, the control unit 55 compares the input value input from the input unit 52 with the reference value read from the storage unit 56 to set the pinching force and the rotation speed. Although the case where the grip members 10a and 10b are controlled in a finite stage has been described above, the grip members 10a and 10b can be set to be more than the stage shown in FIG. Of course, the number of steps shown in FIG. 6 can be further reduced or increased.

  In this way, the holding force of the sheet bundle is changed based on the properties or characteristics of the sheets. The change is made such that the higher the density of the sheet, the stronger the clamping force, and the lower the density, the weaker the clamping force. However, even if the sheet has a high density, there is an upper limit in the pinching force for pinching so as not to leave a trace, and there is a lower limit for holding the sheet bundle. The clamping force is adjusted between the upper limit and the lower limit. Also, the rotational speed of the sheet bundle has a lower limit for productivity and an upper limit because the rigidity of the sheet has a limit. In the meantime, according to the density of the sheet, the higher the density, the higher the rotational speed, and the lower the density, the lower the rotational speed. Of course, both the clamping force and the rotational speed may be changed continuously, but may be changed stepwise as shown in FIG. Further, only the clamping force or only the rotation speed may be controlled according to the density. Further, the angular acceleration may be controlled instead of the rotation speed. Further, the density is used as the property of the sheet. However, if it is assumed that the density of the sheet for printing is not greatly different depending on the paper type, a weighing may be used instead of the density.

[Configuration of bookbinding device]
Next, a bookbinding apparatus 1002 having a sheet processing unit will be described with reference to FIG. The bookbinding apparatus 1002 includes a stacking unit 40 that stacks and aligns printing sheets in a bundle in the casing 30, an adhesive application unit 43 that applies adhesive glue to the sheet bundle from the stacking unit 40, and an adhesive. A cover binding unit 45 is used to bind the cover sheet to the applied sheet bundle.

[Configuration of transport route]
The conveyance path of each sheet will be described. In the casing 30, a carry-in path 31 having a carry-in entrance 26 connected to a paper discharge port of the image forming apparatus 1003 is provided. 34 are connected via a path switching flapper 36. A bookbinding path 33 is connected to the intermediate paper transport path 32 via the stacking unit 40. The bookbinding path 33 is arranged in a direction that cuts the apparatus in a substantially vertical direction, and the cover transport path 34 is arranged in a direction that crosses the apparatus in a substantially horizontal direction.

  The bookbinding path 33 and the cover transport path 34 intersect (orthogonal) each other, and a cover binding section 45 described later is arranged at the intersecting portion. The carry-in path 31 configured as described above is connected to a paper discharge port of the image forming apparatus 1003 and receives a print sheet from the image forming apparatus. In this case, the image forming apparatus 1003 carries out a print sheet (saddle stitching sheet) on which content information is printed and a print sheet (hereinafter referred to as “cover sheet”) on which a title or the like used as a cover cover is printed. . In this way, the carry-in path 31 is branched into the intermediate sheet conveyance path 32 and the cover sheet conveyance path 34, and the print sheets are distributed and conveyed to the respective paths via the path switching flapper 36.

  On the other hand, an inserter device 27 is connected to the carry-in path 31, and is configured so that cover sheets that are not subjected to printing processing by the image forming apparatus 1003 are separated from the paper feed tray 27 a one by one and supplied to the carry-in path 31. . The inserter device 27 is provided with a single-stage or multi-stage paper feed tray 27a, and a paper feed section that separates and feeds stacked sheets one by one at the front end of the tray, and a paper feed section downstream of the paper feed section. A paper path 28 is provided, and this paper feed path is connected to a carry-in path 31 via a path switching piece 29.

  Further, the conveyance roller 31a is provided in the carry-in route 31, the conveyance roller 32a is provided in the intermediate paper conveyance route 32, and the grip conveyance unit (sheet bundle conveyance unit; the same applies hereinafter) 41 and the above-described sheet bundle cutting device (trimmer) are provided in the bookbinding route 33. A unit) and a paper discharge roller (paper discharge unit) 48 are arranged. Further, a transport roller 34a is disposed on the cover transport path 34 and is connected to a drive motor.

[Configuration of stacking unit]
The stacking tray 42 disposed at the paper discharge port 32b of the intermediate paper transport path 32 stacks and stores sheets from the paper discharge port 32b in a bundle. As shown in FIG. 1, the stacking tray 42 is constituted by a tray member arranged in a substantially horizontal posture, and a forward / reverse roller 42a and a carry-in guide 42b are provided above the tray member.

  Then, the print sheet from the paper discharge port 32b is guided onto the stacking tray by the carry-in guide 42b and stored by the forward / reverse roller 42a. This forward / reverse roller 42a transfers the print sheet to the front end side of the stacking tray 42 by forward rotation, and abuts the rear end of the sheet against a regulating member (not shown) arranged at the rear end of the tray (right end in FIG. 1) by reverse rotation. regulate. Further, the stacking tray 42 is provided with a sheet side aligning section (not shown), and both side edges of the printed sheets stored on the tray are aligned to the reference position. With such a configuration, the print sheets from the intermediate paper conveyance path 32 are sequentially stacked on the tray 42 and are aligned in a bundle.

[Grip Conveyor Configuration]
The bookbinding path 33 is provided with a grip conveying section 41 for transferring the sheet from the stacking tray 42 to the adhesive application position E on the downstream side. As shown in FIG. 1, the grip transport unit 41 deflects the sheet bundle stacked on the stacking tray 42 from a horizontal posture to a vertical posture, and the sheet bundle is adhesive along a bookbinding path 33 arranged substantially in the vertical direction. Transfer set to application position E. For this reason, the stacking tray 42 is moved from the stacking position (solid line in FIG. 1) to the transfer position (broken line in FIG. 1), and the sheet bundle is transferred to the grip conveying unit 41 prepared at the transfer position.

[Configuration of adhesive application part]
An adhesive application portion 43 is disposed at the adhesive application position E of the bookbinding path 33. As shown in FIG. 1, the adhesive application unit 43 includes a glue container 43a for storing a hot-melt adhesive, an application roll 43b, and a roll rotation motor (not shown).

[Composition of cover binding part]
A cover binding portion 45 is arranged at the cover binding position F (see FIG. 2) of the bookbinding path 33. As shown in FIG. 1, the cover binding portion 45 includes a back plate 46 a, a back folding plate 46 b, and a folding roll 47. At the cover binding position F, the above cover transport path 34 is arranged, and a cover sheet is fed from the image forming apparatus 1003 or the inserter 27.

  The back plate 46b is formed of a plate-like member that backs up the cover sheet, and is disposed in the bookbinding path 33 so as to be able to advance and retreat. A sheet bundle (inner paper) is joined in an inverted T shape to the cover sheet supported by the back plate 46b. Therefore, the back folding plate 46b is composed of a pair of left and right press members, and is configured to approach and separate from each other by a drive unit (not shown) in order to do the back folding of the back part of the cover sheet joined in an inverted T shape. . Further, the folding roll 47 is composed of a pair of rollers for clamping and finishing the back-folded sheet bundle.

  The sheet bundle that has been bound and bound with the cover binding section is conveyed to a sheet bundle cutting apparatus located downstream thereof, and is cut in a pinched state as described with reference to FIGS. The fore edge portion and the ground portion are sequentially rotated and cut.

  On the downstream side of the cutting position Cp (see FIG. 2), a paper discharge roller (paper discharge unit) 48 and a storage stacker 50 are arranged. As shown in FIG. 1, the storage stacker 50 is arranged in a drawer shape on the casing 30 and can be pulled out to the front side of the apparatus (the front side in FIG. 1). The user can visually recognize from the upper surface direction in a state of being pulled out to the front side of the apparatus.

  On the other hand, the bookbinding path 33 constitutes a sheet discharge path 33a for guiding a sheet bundle from the cover binding position F to the storage stacker 50, and a sheet discharge roller 48 is disposed in the sheet discharge path 33a. The paper discharge roller 48 includes a pair of rollers and forms a paper discharge unit that nips the sheet bundle and guides it to the storage stacker 50. A waste storage box 51 is provided in parallel with the storage stacker 50 below the cutting position Cp, and stores a piece of paper cut by the cutting blade 22.

[Configuration of control unit]
Next, the configuration of the control unit 55 in the above-described apparatus will be described with reference to FIG. In a system in which an image forming apparatus 1003 and a bookbinding apparatus 1002 as shown in FIG. 1 are connected, for example, an image forming apparatus control unit 53 provided in the image forming apparatus 1003 is provided with an input unit 52 and a mode setting unit 54. The control unit includes, for example, a CPU. The control unit of the bookbinding apparatus 1002 is provided with a bookbinding apparatus control unit (hereinafter simply referred to as a control unit) 55, and this control unit 55 has a CPU that calls a bookbinding process execution program from the ROM 57 and executes each process in the bookbinding path 33. . The control unit 55 also receives a post-processing mode instruction signal, a job end signal, sheet size information, and other information required for bookbinding and a command signal from the control unit 53 of the image forming apparatus 1003. On the other hand, a sheet sensor (not shown) for detecting a sheet (sheet bundle) to be conveyed is arranged in the carry-in path 31, the bookbinding path 33, and the cover sheet conveying path 34, respectively. Therefore, the detection signal of each sheet sensor is transmitted to the control CPU 55. The control CPU 55 includes a “stacking unit control unit 5501”, an “adhesive application unit control unit 5502”, a “cover binding unit control unit 5503”, a “cutting unit control unit 5504”, and a “stack control unit 5505”. Each process is controlled and executed by each control unit. Among them, the cutting unit control unit 5504 executes bookbinding processing according to the flowchart shown in FIG. The cutting unit control unit 5504 may be realized by executing a program by the bookbinding apparatus control CPU (control unit) 55.

[Explanation of cutting operation]
The procedure of the cutting operation will be described with reference to FIG. The control unit 55 sets the pinching force and the rotation speed when pinching the sheet bundle. In this pinching force and rotation speed setting, the properties of the sheets constituting the sheet bundle are acquired by the input value from the input unit 52 or the detection value from the detection unit (St01). The density of the sheet bundle is set from the property value of the sheet (St02). The density of the sheet bundle is compared with a reference value (for example, shown in FIG. 6) set in advance and stored in the storage unit (RAM) 56 (St03). As described above, the pinching force and rotation speed are set so that the pinching force is set high when the density is high and damage is difficult, and the pinching force is weakened and the rotation speed is slow when the density is low and easy to damage. To do.

  The control unit 55 holds the sheet bundle with the set holding force (St04). Since the stepping motor serves as a power source, for example, the clamping force may be controlled by, for example, providing a sensor that detects that the gripping member 10a is in contact with the sheet bundle, and the number of steps from there. Alternatively, a pressure sensor may be provided and controlled according to the output signal. The control unit 55 executes the cutting operation according to the determination as to whether or not to perform the cutting alignment set by the operator from the control panel (input unit) 52 or the like (St05).

  When executing the cutting operation, the control unit 55 calculates the cutting amount (St06). At this time, when cutting in one direction, the cutting amount of the fore edge is calculated. In the three-way cutting, the cutting amount is calculated according to a preset cutting order. The cutting amount is the width of the portion to be cut off. The cutting amount is calculated by, for example, calculating the cutting amount from the size in the fore edge direction (sheet size−finishing size = cutting amount) when considering the cutting edge, and considering the calculated value, the minimum cutting amount, and the maximum cutting amount. Determine the amount of trimming. In the case of three-way cutting, the edge portion is calculated in the same manner, and the cutting amount between the top and the ground is calculated by [(sheet size−finishing size) × 1/2 = cutting amount]. The cutting amount to be executed is determined in consideration of the minimum cutting amount and the maximum cutting amount. In this case, the minimum trimming amount is set from the minimum cut width to be trimmed and the maximum trimming amount is set from the reserved area of the sheet. When the calculated value is smaller than the minimum trimming amount or larger than the maximum trimming amount, the minimum trimming amount is set. Alternatively, the cutting amount for executing the maximum cutting amount is set.

  The controller 55 rotates the sheet bundle at the set rotation speed (St07). The rotation direction and rotation angle at this time are preset. For example, at the time of one-way cutting, in a configuration in which the back part is gripped toward the cutting position Cp, the sheet bundle is gripped and rotated 180 degrees so that the fore edge part faces the cutting position Cp. Further, in a configuration in which the back portion is removed from the cutting position and gripped at the time of three-way cutting, the sheet bundle is gripped and rotated by 90 degrees so that the top portion or the fore edge portion faces the cutting position Cp.

  Then, the control unit 55 rotates the rotation speed of the sheet bundle at the speed specified in step St03. This speed is set so that the average speed (average of rising speed, constant speed, falling speed) or maximum speed does not exceed the set speed.

  When the control unit 55 deflects the posture of the sheet bundle in a predetermined direction (the cutting edge faces the cutting position), the control unit 55 sets the sheet bundle to the cutting position Cp (St08). At this time, the sheet bundle is set so that the cutting amount is between the cutting edge of the sheet bundle and the cutting line of the cutting blade.

  And the control part 55 presses a sheet | seat bundle with the cutting edge press member 17 (St09). Next, the cutter motor Mc is operated to perform cutting with the cutting blade 22 (St10). After the cutting operation is finished, the sheet bundle pressing is released (St11).

  When cutting the remaining edge after executing the cutting operation, the control unit 55 returns to step St07 and repeatedly executes the same operation. After finishing cutting all the edges, the control unit 55 carries out the sheet bundle to the downstream side of the trimmer unit (St13).

  With the above configuration and control procedure, the bookbinding apparatus according to the present embodiment controls the force for holding the sheet bundle and the rotation speed according to the properties, for example, density, of the sheets constituting the sheet bundle. For example, a density threshold is provided for a sheet bundle made of standard density sheets, and the clamping force and the rotation speed are set for each density range divided by the threshold. The setting reduces the pinching force and lowers the rotational speed for the sheet bundle of lower density sheets. Conversely, for a sheet bundle of higher density sheets, the clamping force is increased and the rotational speed is increased. As shown in FIG. 6, the number of stages of the rotational speed and the clamping force may not be the same so that the rotational speed is two stages and the clamping force is three stages. In that case, when one of the clamping force and the rotational speed reaches the upper limit or lower limit at a certain sheet density, the value is changed and set only for a setting item that has a margin before either the upper limit or the lower limit.

[Summary of Embodiment]
The sheet bundle cutting apparatus according to the above embodiment can be summarized as follows. That is, a control unit is provided that includes a clamping unit that rotatably clamps a sheet bundle, a cutting unit that clamps the edge of the sheet bundle that is clamped by the clamping unit and is set at a cutting position, and a control unit. Controls the clamping unit to clamp the sheet bundle with a force according to the property of the sheet bundle, or to rotate the sheet bundle at a rotation speed according to the property of the sheet, or both.

  Further, the property of the sheet is the density of the sheets constituting the sheet bundle, and the control unit increases the force for sandwiching the sheet bundle if the sheet density is higher, or if the density of the sheet is higher. The clamping unit can be controlled to increase the rotation speed.

  Furthermore, the control unit can determine the density of the sheet based on the input weighing and thickness of the sheet.

  Further, the control unit can control the force for sandwiching the sheet bundle and / or the rotation speed of the sheet bundle based on the density input by the user.

  Further, when the density of the sheet is less than the predetermined threshold, the control unit weakens the force for clamping the sheet bundle with respect to the case where the sheet density is equal to or higher than the predetermined threshold, and the rotation speed of the sheet bundle. Can be reduced.

  Further, the control unit, when the density of the sheet is lower than the first threshold, with respect to the case where the density of the sheet falls within a predetermined range (a range that is equal to or higher than the first threshold and lower than the second threshold). When the force for pinching the sheet bundle is weakened and the rotation speed of the sheet bundle is decreased and the sheet density is equal to or higher than the second threshold, the sheet bundle is compared with the case where the sheet density falls within a predetermined range. The force to pinch can be made stronger.

  As described above, by controlling the clamping force of the sheet bundle at the time of cutting, or the clamping force and the rotation speed, the sheet bundle is prevented from being damaged and misaligned in the cutting process, and high productivity is achieved. Can be maintained.

Alternatively, the sheet bundle cutting device according to the above embodiment can be grasped as a sheet bundle clamping device and can be summarized as follows. That is, a clamping unit that clamps the sheet bundle with a predetermined clamping force;
A control unit for changing a predetermined clamping force according to the sheets constituting the sheet bundle sandwiched by the clamping unit;
Have

  More preferably, the sandwiching portion is rotatable at a predetermined rotational speed while sandwiching the sheet bundle, and the control unit has a predetermined rotational speed according to the sheets constituting the sheet bundle sandwiched by the sandwiching portion. Change it.

  More preferably, the control unit changes the predetermined clamping force based on the properties of the sheets constituting the sheet bundle.

  More preferably, the property of the sheet is the density of the sheets constituting the sheet bundle.

  More preferably, the predetermined rotational speed is changed in addition to changing the predetermined clamping force based on the density of the sheet.

  More preferably, when the density of the sheet is equal to or higher than the first predetermined value, the control unit increases the holding force for holding the sheet bundle more than the predetermined holding force, and the density of the sheet is the first predetermined value. If it is equal to or smaller than a second predetermined value that is smaller than the predetermined value, it is made smaller than a predetermined clamping force.

  More preferably, when the density of the sheet is equal to or higher than the first predetermined value, the control unit increases the rotation speed for rotating the sheet bundle to be higher than the predetermined rotation speed so that the sheet density is the first predetermined value. If it is equal to or smaller than a second predetermined value that is smaller than the value, it is made slower than a predetermined rotation speed.

  More preferably, the control unit obtains the density based on the input weighing and thickness of the sheet.

  More preferably, the control unit controls the clamping force and / or the rotational speed based on the density input by the user.

  More preferably, the control unit changes a predetermined clamping force based on the state of the sheet bundle.

  More preferably, the state of the sheet bundle is the thickness of the sheet bundle.

  More preferably, a control part calculates | requires thickness based on the thickness of the sheet | seat which comprises a sheet | seat bundle.

  Also with the above configuration, it is possible to prevent damage and displacement to the sheet bundle due to the sandwiching of the sheet bundle, and to maintain high productivity with respect to the processing of the sandwiched sheet bundle.

(Other embodiments)
In the above-described embodiment, the configuration is such that both the clamping force and the rotation speed are changed according to the density of the sheet. However, if at least the clamping force is changed, damage to the sheet bundle and misalignment can be prevented. If the rotation speed is set to a rotation speed at which the sheet bundle can be rotated in a state where the clamping force is the weakest, the present invention can be applied to a configuration in which the rotation speed is not changed.

  In the embodiment described above, the clamping force and the rotation speed are changed according to the density of the sheet. However, the application of the present invention is not limited to this, and the surface property of the sheet, the amount of the sheet bundle, and the thickness. For example, a configuration in which at least one of the clamping force and the rotation speed is changed according to the characteristics and state of the sheet bundle to be clamped, or a configuration in which the sheet bundle is clamped with a higher clamping force than usual depending on the characteristics of the sheet bundle. However, the present invention can be applied.

  1001 Sheet bundle cutting device (trimmer unit), 1002 Bookbinding device, Cp cutting position, 10 Sheet bundle rotating unit, 10a First rotating member (first grip member), 10b Second rotating member (second grip member), 17 Cutting Edge press part, 20 cutting part (cutter mechanism)

Claims (14)

Clamping means for clamping the sheet bundle with a predetermined clamping force;
Control means for changing the predetermined holding force according to the sheets constituting the sheet bundle held by the holding means;
A sheet bundle clamping device comprising: The sandwiching means is rotatable at a predetermined rotational speed while sandwiching the sheet bundle, and the control means performs the predetermined rotational speed according to the sheets constituting the sheet bundle sandwiched by the sandwiching means. The sheet bundle clamping device according to claim 1, wherein the sheet bundle clamping device is changed. 3. The sheet bundle clamping device according to claim 1, wherein the control unit changes the predetermined clamping force based on a property of a sheet constituting the sheet bundle.   The sheet bundle clamping device according to claim 3, wherein the property of the sheet is a density of sheets constituting the sheet bundle.   The sheet bundle clamping device according to claim 4, wherein the predetermined rotation speed is changed in addition to changing the predetermined clamping force based on the density of the sheets.   When the density of the sheet is equal to or higher than a first predetermined value, the control unit increases a holding force for holding the sheet bundle to be larger than the predetermined holding force, and the density of the sheet is the first density. 6. The sheet bundle clamping device according to claim 4, wherein when the value is equal to or smaller than a second predetermined value smaller than a predetermined value, the sheet holding force is made smaller than the predetermined clamping force.   When the density of the sheet is equal to or higher than a first predetermined value, the control unit increases a rotation speed for rotating the sheet bundle to be higher than the predetermined rotation speed so that the density of the sheet is the first density. The sheet bundle clamping device according to any one of claims 4 to 6, wherein when the predetermined value is equal to or smaller than a second predetermined value smaller than the predetermined value, the rotation speed is slower than the predetermined rotation speed.   The sheet bundle clamping device according to any one of claims 4 to 7, wherein the control unit obtains the density based on the input weighing and thickness of the sheet.   The sheet bundle nipping according to any one of claims 4 to 8, wherein the control unit controls the nipping force and / or the rotation speed based on a density input by a user. apparatus. The sheet bundle clamping device according to claim 1, wherein the control unit changes the predetermined clamping force based on a state of the sheet bundle. The sheet bundle clamping device according to claim 10, wherein the state of the sheet bundle is a thickness of the sheet bundle. The sheet bundle clamping device according to claim 11, wherein the control unit obtains the thickness based on a thickness of a sheet constituting the sheet bundle. A sheet bundle clamping device according to claim 1;
Cutting means for moving the sheet bundle with the sheet bundle clamping device and cutting the sheet bundle at a cutting position;
A sheet bundle cutting apparatus comprising: Image forming means for forming an image on a sheet;
A binding unit that forms a sheet bundle by binding and binding sheets on which images are formed by the image forming unit;
A bookbinding apparatus comprising the sheet bundle cutting apparatus according to claim 13.

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