JP2013245031A - Sheet stacking unit and printing machine provided with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet stacking unit capable of accurately stacking sheets conveyed at high speed.SOLUTION: In a sheet stacking unit 20, a sensor 23 transmits a sheet detection signal to a control device when detecting that a distal end in a traveling direction or a rear end in the traveling direction of a sheet has passed through a predetermined position, the control device starts to count pulses output from a pulse output device 24 according to the sheet detection signal from the sensor. When the number of counted pulses becomes equal to or exceeds a preset air injection timing value, an air injection mechanism 25 starts injecting air, and when the number of counted pulses exceeds or becomes equal to a preset air injection stop timing value, the air injection mechanism 25 stops injecting air, to stack sheets in a stacking part 21.

Description

  The present invention relates to a sheet stacking unit used in a printing press and a printing press equipped with the sheet stacking unit, and in particular, controls ejection timing of air sprayed directly onto a sheet to prevent sheet discharge errors and paper jams. The present invention relates to a sheet accumulating unit capable of printing and a printing press including the sheet accumulating unit.

  In a printing machine that prints a number of sheets continuously, conveys them continuously, stacks them continuously, and stacks them, when releasing the sheets from the gripping mechanism at the stacking unit and throwing them into the sheet stacking unit to stack the sheets In addition, the front end of the seat in the traveling direction falls toward the ground before the rear end. Therefore, there is a possibility that the leading end in the traveling direction of the succeeding sheet contacts the trailing end in the traveling direction of the preceding sheet. If the trailing edge of the preceding sheet in the running direction contacts the leading edge of the succeeding sheet in the running direction, a paper discharge error or a paper jam occurs, and printing efficiency is significantly reduced. In particular, recent large-scale printing presses can print tens of thousands and thousands of sheets in a short time, so if the printing press does not cause a paper discharge error or a paper jam with a probability close to 0%. This causes troubles such as paper jams and paper discharge errors many times a day, which is very troublesome.

  In order to avoid and alleviate these problems, sheet stacking units have been developed that have been variously devised. For example, the following Patent Document 1 discloses a sheet stacking unit that includes a sheet discharge conveyance table, a jump table, a fan, an abutment plate, and a sheet discharge table. A technique is described in which a space is formed by a sheet hit against the wall of the stacking portion, the space is made negative by a fan, the sheets are attracted, and the sheets are stacked, thereby preventing the sheets from rising irregularly.

  Here, FIG. 7 shows an example of the sheet stacking apparatus 50 described in Patent Document 1. As shown in the partial diagrams (a) to (d) in FIG. 7, the sheet stacking device 50 of Patent Document 1 includes a jump base 53, a fan 54, and a butting plate 55. In the sheet stacking apparatus 50, when the sheet 51 passes through the jump table 53 on the sheet discharge conveyance table, the sheet 51 is curled from both ends and conveyed to the sheet discharge table 56 while being seated. At this time, the fan 54 is operating, but the sheet 51 is strongly attracted and transported vigorously, so it is not attracted downward. Rather, as shown in the partial diagram (b) of FIG. 7, the wind pressure is raised from below in the traveling direction due to the interaction between the jump base 53 and the conveyance speed, and the air rises. When the leading end of the sheet 51 approaches the butting plate 55, the sheet 51 closes the upper part of the sheet discharge table, so that the fan 54 is discharged by the action of the fan 54 as shown in the partial view (c) of FIG. The inside of the paper board 56 becomes negative pressure, and the sheet 51 starts to be attracted downward. At this time, since the sheet 51 still maintains a certain conveyance speed, the wind pressure acts on the front end of the sheet 51, and the rear end is lower than the front end. When the leading edge of the sheet 51 comes into contact with the abutting plate 55, the sheet is moved from its rear end to the inside of the sheet discharge table 56 by its own weight and the action of the fan 54, as shown in a partial diagram (d) of FIG. Is housed in. At this time, the succeeding sheet 52 has been conveyed, but the trailing end of the preceding sheet 51 in the traveling direction is forcibly attracted downward by the fan 54, so Thus, the sheet stacking apparatus 50 can avoid the collision with the leading end of the sheet 52 in the traveling direction, and can stack the sheets appropriately without jamming.

JP-A-8-91665

  However, the sheets stacked by the sheet stacking apparatus are not necessarily the same in terms of thinness, weight, shape, material, and the like. In the conventional sheet stacking apparatus 50 described in Patent Document 1 listed above, the sheet 51 receives wind pressure from below until it is abutted against the abutting plate 55. If the paper has a certain amount of weight, the movement becomes stable. For example, when stacking very light sheets, even if it is a short distance until it hits the abutting plate 55, it is affected by the wind pressure from below. There is a risk of a soaring more than expected. Therefore, satisfactory stacking cannot be realized depending on the paper conditions, and a sheet stacking unit capable of handling paper of any material has been demanded.

  The present invention has been made in view of the problems existing in the above-described prior art, and its purpose is to reliably stack sheets without causing paper jams under any conditions. It is an object of the present invention to provide a sheet stacking unit that can perform the above.

  A sheet stacking unit according to the present invention includes a paper feeding unit that feeds continuous paper, a printing unit that prints on continuous paper, a cutting unit that cuts the printed continuous paper into individual sheets, and a cut sheet Used in a printing machine having a high-speed conveyance unit that conveys, a sheet accumulation unit that releases sheets conveyed at a predetermined position, and stacks sheets on a stacking unit, and a control device that controls the operation of the sheet accumulation unit. A sensor for detecting that a leading end or a trailing end in the traveling direction of a sheet has passed a predetermined position, and a pulse output device capable of outputting a pulse in accordance with a conveyance state of the conveyed sheet And an air injection mechanism for injecting air to the sheets when the sheets are stacked on the stacking portion, and the sensor When it is detected that the leading end or the trailing end of the traveling direction of the sheet has passed a predetermined position, a sheet detection signal is transmitted to the control device, and the control device, in accordance with the sheet detection signal from the sensor, The pulse output machine starts counting pulses, and when the counted number of pulses exceeds or is equal to a preset air injection timing value, the air injection mechanism is injected with air. The air injection mechanism is configured to stop the air injection when the counted number of pulses exceeds or becomes equal to a preset air injection stop timing value. .

  In the sheet stacking unit according to the present invention, the air injection timing value is set by an ON setting value and an ON adjustment value, and the air injection stop timing value is set by an OFF setting value and an OFF adjustment value, and the ON The adjustment value and the OFF adjustment value are set as unit values smaller than the ON setting value and the OFF setting value so that the respective values of the ON setting value and the OFF setting value can be finely adjusted. Can be.

  In the sheet stacking unit according to the present invention, the control device may stop the air injection on the preceding sheet by the air injection mechanism, and then the sensor may start or follow the traveling direction of the subsequent sheet. By detecting that the end has passed the predetermined position, the counting of the pulses output by the pulse output device can be stopped and the counted number of pulses can be reset.

  A printing machine according to the present invention includes a paper feeding unit that feeds continuous paper, a printing unit that prints on continuous paper, a cutting unit that cuts the printed continuous paper into individual sheets, and transports the cut sheets And a controller that controls the operation of the sheet stacking unit, the sheet stacking unit that releases the sheet transported at a predetermined position, and stacks the sheets on the stacking unit. The sheet stacking unit includes a sensor that detects that a leading end or a trailing end in the traveling direction of a sheet has passed a predetermined position, a pulse output device that can output a pulse according to a conveyance state of the conveyed sheet, and a sheet An air injection mechanism for injecting air to the sensor, wherein the sensor is such that a leading end or a trailing end in the traveling direction of the seat has passed a predetermined position. When detected, a sheet detection signal is transmitted to the control device, and the control device starts counting pulses output by the pulse output device in response to the sheet detection signal from the sensor, and the counted pulses When the number exceeds or becomes equal to a preset air injection timing value, the air injection mechanism starts to inject air, and the counted number of pulses is set to a preset air injection stop timing. When the value exceeds or becomes the same, the air injection mechanism stops the air injection.

  In the printing machine according to the present invention, an encoder is used as the pulse output machine, and pulses are generated by connecting the encoder to a conveyance mechanism for conveying individual sheets cut by the cutting unit. be able to.

  In the printing press according to the present invention, the transport unit can transport the transport speed after cutting the sheet at a speed faster than the transport speed before cutting the sheet.

  According to the sheet stacking unit of the present invention, it is possible to reliably push down the sheets by directly injecting air onto the sheets, and the sheets can be stably stacked regardless of the conditions of the sheets. Therefore, it is possible to provide a printing machine that can reduce the human burden in consideration of the occurrence of a paper jam and can perform printing at high speed without reducing printing efficiency.

  Further, in the sheet stacking unit according to the present invention, since the control of air injection is started by using the detection signal of the sensor as a trigger, there is no need for the operator to adjust the timing of injecting air to the sheet through trial and error. Therefore, the work burden can be reduced.

  Furthermore, in the sheet stacking unit according to the present invention, since the amount of air to be sprayed can be set to a necessary and sufficient amount, the sheets can be appropriately stacked, and an energy saving effect can be obtained. .

It is the schematic which shows the printing line of a printing machine provided with the sheet | seat integration | stacking unit which concerns on this embodiment. It is a figure which shows the inside of the sheet | seat stacking unit which concerns on this embodiment, the cutting | disconnection unit and conveyance unit which are continued to a sheet | seat stacking unit. It is an enlarged view showing the inside of the sheet stacking unit according to the present embodiment. It is a figure which shows the screen of the control apparatus which concerns on this embodiment. It is a flowchart figure which shows the operation | movement relevant to the sensor 23, the control apparatus 11, and the air injection mechanism 25 in the sheet | seat integrated unit 20 which concerns on this embodiment. It is a schematic diagram showing a flow of sheet stacking in the sheet stacking unit according to the present embodiment. It is a reference diagram showing a sheet stacking unit according to the prior art.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments for carrying out the invention will be described with reference to the drawings. The following embodiments do not limit the invention according to each claim, and all combinations of features described in the embodiments are not necessarily essential to the solution means of the invention. Absent.

  FIG. 1 is a schematic diagram illustrating a printing line of a printing press 10 including a sheet stacking unit 20 according to the present embodiment. FIG. 2 is a diagram showing the inside of the sheet stacking unit 20 according to the present embodiment, and the cutting unit 14 and the conveyance unit 15 connected to the sheet stacking unit. FIG. 3 is an enlarged view showing the inside of the sheet stacking unit 20 according to this embodiment. Furthermore, FIG. 4 is a figure which shows the screen of the control apparatus 11 which concerns on this embodiment.

  The printing press 10 according to the present embodiment includes a control device 11, a paper feeding unit 12, a printing unit 13, a cutting unit 14, a high-speed conveyance unit 15, a sheet stacking unit 20, and a conveyance mechanism 30. The The printing press 10 according to the present embodiment is configured to convey sheets in the order of a paper feeding unit 12, a printing unit 13, a cutting unit 14, a high-speed conveyance unit 15, and a sheet stacking unit 20.

  The control device 11 according to the present embodiment is a device including at least a signal transmission / reception unit, a control unit, a storage unit, a display unit 41, and an operation reception unit, and specifically includes a microcomputer or the like. It is configured as a built-in control unit. For the control device 11 according to the present embodiment, an audio output unit or the like may be provided as another constituent member. In the present embodiment, as shown in FIG. 1, the control device 11 is provided outside the unit constituting the printing press 10, but may be inside any one of the units. A plurality of control devices may be used.

  In particular, the signal transmission / reception unit in the control device 11 receives a sheet detection signal from the sensor 23 and transmits an electric signal to the air injection mechanism 25. Note that the method of signal transmission / reception in the signal transmission / reception unit does not matter whether it is wired or wireless. In addition, the control unit counts the number of pulses output by the pulse output device 24 in response to receiving the sheet detection signal, and the number of counted pulses exceeds the threshold value or becomes equal to the threshold value. Judgment is made.

  Further, the storage unit in the control device 11 stores the ON setting value 42 and the OFF setting value 43 set as threshold values. The ON setting value 42 here is a numerical value set for the injection timing for causing the air injection mechanism 25 to inject air, and the OFF setting value 43 is for the stop timing for causing the air injection mechanism 25 to stop air injection. It is the set numerical value. Both the ON setting value 42 and the OFF setting value 43 can be input from the display unit 41. In addition, since it is necessary to inject air only to the appropriate position of the sheet that has been conveyed one after another and has reached the air injection position, in order to realize a configuration that does not continue to inject air An ON set value 42 and an OFF set value 43 are provided.

  Further, as shown in FIG. 4, the storage unit in the control device 11 includes an ON adjustment value 44 and an OFF adjustment value 45 that finely adjust each of the set ON setting value 42 and OFF setting value 43. Highly preferred.

  The air injection start timing or the injection stop timing value is obtained based on the distance between the sensor 23 and the air injection mechanism 25, and is set as a constant value as the ON set value 42 and the OFF set value 43. However, the time from the detection of the seat to the start of air injection includes the signal transmission time, the operation time of the electrically driven valve, and the arrival of air from when the air is injected until it reaches the seat. There is a delay time such as time, and such a delay time is very small, but is an unavoidable error due to the configuration of the apparatus. Since the sheet jumping speed increases as the sheet is conveyed at a high speed, even if a slight error occurs, the deviation of the air injection position with respect to the sheet becomes large, which may cause an error that cannot be overlooked.

  Therefore, in addition to setting the ON setting value 42 and the OFF setting value 43 as basic numerical values that can be calculated from the distance from the sheet detection position of the sensor 23 to the air injection position, the ON adjustment value 44 The OFF adjustment value 45 can be input and set, and each numerical value is stored in the control unit 11. Then, fine adjustment of the injection timing value is realized using an arithmetic expression that divides the ON adjustment value 44 and the OFF adjustment value 45 that are set by input by a relatively large number.

  In the present embodiment, an arithmetic expression “(ON setting value or OFF setting value) − (ON adjustment value / 150 or OFF adjustment value / 150) = air injection timing value or air injection stop timing value (rounded down after the decimal point)”. Is stored in the control device 11. A numerical value “50” is input to the ON setting value 42, a numerical value “70” is input to the OFF setting value 43, and a numerical value “30” is input to each of the ON adjustment value 44 and the OFF adjustment value 45. At this time, the numerical value “0.2” obtained by dividing the ON adjustment value 44 and the OFF adjustment value 45 by “150” is subtracted from the respective input setting values of the ON setting value 42 and the OFF setting value 43. That is, very small numerical values are handled for the ON setting value 42 and the OFF setting value 43, and fine adjustment is possible.

  In the above-described embodiment, the ON adjustment value 44 and the OFF adjustment value 45 are minus with respect to the ON setting value 42 and the OFF setting value 43, but may be plus instead of minus. Further, it may be possible to select plus or minus with an operation panel or an operation button.

  In this way, by using the ON adjustment value 44 and the OFF adjustment value 45 and finely adjusting the delay time that fluctuates depending on the change of the sheet condition, the human burden and the work burden are reduced, and the sheet condition Even when is changed, an accurate injection position can be easily set.

  Further, as shown in FIG. 4, the display unit 41 in the control device 11 displays the number of pulses currently counted, the number of pulses set as the ON setting value 42, the number of pulses set as the OFF setting value 43, and the like. Is done. The ON setting value 42 and the OFF setting value 43 may be set using an operation panel or an operation button provided on the display unit 41. Note that the operation panel or operation buttons used for inputting and setting numerical values are not necessarily provided on the display unit 41, and remote operation may be possible using an operation means such as a remote controller, for example.

  The paper feed unit 12 according to this embodiment is a unit for setting paper. In the present embodiment, it is assumed that the paper to be fed is continuous paper such as winding paper.

  The printing unit 13 according to the present embodiment is a unit that performs continuous printing on continuously fed paper. The printing method executed by the printing unit 13 may be digital printing or analog printing. Further, single-sided printing or double-sided printing may be used.

  The cutting unit 14 according to the present embodiment is a unit that cuts continuously fed continuous paper with a predetermined length in order to make continuous paper into individual sheets.

  The high-speed conveyance unit 15 according to the present embodiment is a unit for high-speed conveyance while holding individual sheets cut by the cutting unit 14. After the continuous sheet is cut into individual sheets, the trailing end of the preceding sheet in the running direction and the leading end of the following sheet in the running direction may collide, and the posture of the sheet being conveyed may be disturbed. Therefore, the high-speed conveyance unit 15 according to the present embodiment conveys the sheet so that the conveyance speed of the sheet after cutting is faster than the conveyance speed of the sheet before cutting. By increasing the sheet conveyance speed, a speed difference is generated between the preceding sheet and the succeeding sheet, and a gap is generated between the preceding sheet and the succeeding sheet. Transport and stacking are possible.

  The sheet stacking unit 20 according to the present embodiment is a unit that continuously stacks individual sheets fed continuously from the high-speed conveyance unit 15 to form a sheet stack. As shown in more detail in FIG. 3, the sheet stacking unit 20 includes a stacking unit 21, a butting plate 22, a sensor 23, a pulse output machine 24, and an air injection mechanism 25. In addition, it is preferable to adjust the conveyance speed in the sheet stacking unit 20 so that the speed increased by the high-speed conveyance unit 15 is maintained or further increased.

  The stacking unit 21 is a portion where the sheets transported from the high-speed transport unit 15 are stacked. As shown in FIG. 3, the deposition part 21 is preferably provided with an inclination. By being formed with an inclination angle, the sheets are conveyed along the inclination and are stacked in a state aligned with the inclination angle.

  The abutting plate 22 is a plate-like member that plays a role of a wall so that a sheet that jumps out in the traveling direction does not exceed the accumulation portion 21. The butting plate 22 is preferably made of a material that does not damage the sheet that collides vigorously.

  The sensor 23 is for detecting a sheet conveyed by the high-speed conveyance unit 15, and transmits a sheet detection signal to the control device 11 when the sheet is detected. The sensor 23 and the control device 11 may be connected by wire or wireless, or may be detected by the control device 11 even if they are not connected.

  The sensor 23 includes a projector and a light receiver that are generally used as photoelectric switches. The presence / absence of the sheet is detected by detecting whether the object blocks the light passing between the projector and the light receiver, or whether the blocked light is transmitted. In other words, the conveyed sheet is conveyed so that there is a moment when the light passing through between the projector and the light receiver constituting the sensor 23 is blocked, and the sensor 23 conveys such a sheet. What is necessary is just to be arrange | positioned on the path | route. In addition, about the sensor applicable to this invention, you may employ | adopt not only the photoelectric switch comprised by a light projector and a light receiver but what comprised a light projector and a light receiver integrally. In addition, a sensor other than the photoelectric switch may be used as the sensor according to the present invention as long as the predetermined state can be detected with high accuracy.

  The timing for transmitting the sheet detection signal to the control device 11 may be set so that it can be transmitted at substantially the same position with respect to the conveyed sheet. For example, when the sheet travels so as to block the light of the sensor 23 that transmits light, and the light that has been blocked with the passage of the sheet passes, the timing for transmitting the sheet detection signal may be used. In this case, the trailing end of the sheet in the traveling direction can be detected every time the sheet passes the detection position of the sensor 23 based on the detection timing. On the other hand, if the timing for transmitting the sheet detection signal when the light passing therethrough is blocked by the sheet, the leading edge of the sheet in the traveling direction can be detected. As described above, in the present invention, various conditions can be set for the timing at which the sheet detection signal is transmitted to the control device 11.

  As for the arrangement position of the sensor 23, it is preferable that the sheet on the conveyance path is installed immediately before the position where the sheet jumps out of the conveyance mechanism 30. The sensor according to the invention may be installed anywhere. For example, if the sensor 23 is installed immediately before the position where the sheet jumps out of the conveyance mechanism, the pulse counted by the control device 11 until the subsequent sheet is detected can be reset, and the air injection can be performed. The timing deviation will be reduced.

  The pulse output machine 24 according to the present embodiment outputs pulses according to the conveyance state of the high-speed conveyance unit 15. In the present embodiment, the pulse output device 24 that generates a pulse when a rotational motion such as a rotary encoder is applied is used. The pulse output machine 24 of this embodiment including a rotary encoder is connected to a shaft member, a transport belt, and the like that form the high-speed transport unit 15. It is configured to output a pulse by taking a rotary motion and rotating a rotary encoder.

  If the pulse output device 24 is configured in this way, the sheet conveyance speed and the rotation speed of the rotary encoder become substantially the same. Therefore, if the sheet conveyance speed decreases, the rotation speed of the rotary encoder also decreases, and a pulse is output. The timing to perform this can be understood by looking at the sheet conveyance distance. That is, the sheet conveyance distance is proportional to the total number of pulses output by the encoder.

  Since the transport distance of the sheet is proportional to the total number of pulses output from the encoder, and the installation position of the air injection mechanism 25 is fixed from the installation position of the sensor 23, air is injected from the installation position of the sensor 23. If the distance to the installation position of the mechanism 25 is measured in advance and the distance necessary to output a pulse once is known, the air is applied to the sheet from when the sensor 23 detects the sheet. It is possible to grasp the approximate number of pulses required until the sheet moves to a position where it can be accurately injected. The numerical value may be set as the ON setting value 42.

  At the same time, the sensor 23 detects the sheet until the sheet finishes receiving the air injection from the air injection mechanism 25 and moves toward the abutting plate 22 provided in the stacking portion 21. Since the number of pulses can also be grasped, the numerical value may be set as the OFF setting value 43.

  As described above, a device that generates a pulse when a rotary motion such as a rotary encoder is applied is used as the pulse output machine 24, and the rotary encoder is connected to a shaft member, a conveyor belt, or the like forming the high-speed conveyance unit 15, and the high-speed conveyance unit. If the rotary encoder is rotated in conjunction with the 15 sheet conveyance to output a pulse, the ON set value 42 and the OFF set value 43 can be easily set. Not only that, the numerical values set in this way are substantially constant regardless of conditions such as sheet conveyance speed, sheet quality, weight and shape, so every time the type of sheet to be conveyed is changed, It is not necessary to change the set numerical value, and the human burden and work burden can be greatly reduced.

  The air injection mechanism 25 according to the present embodiment is a mechanism composed of an air injection nozzle and an electrically driven valve, and can inject air supplied from a compressor (not shown) or the like. As the electrically driven valve, an electromagnetic valve can be used, and by opening and closing the electromagnetic valve in accordance with an electric signal from the control device 11, it is possible to execute air injection and stop. Become.

  The installation position of the air injection mechanism 25 is preferably a position immediately after the sheet jumps out of the high-speed conveyance unit 15 and a position where air can be injected substantially perpendicularly to the upper surface of the sheet. Moreover, the position which can inject air substantially perpendicularly with respect to the lower surface of a sheet | seat from the lower part may be sufficient. When injecting air from the upper part, time should be injected from the center of the seat to the trailing edge of the running direction, and when injecting air from the lower part of the seat, from the center of the seat to the leading end of the running direction. Then, the timing should be measured so as to inject air.

  Moreover, it is good also as a structure provided with the several air injection mechanism 25. FIG. For example, if a plurality of air injection mechanisms 25 are provided so as to cover the lateral width of the seat in the traveling direction of the seat, the entire lateral width can be pushed down or pushed up evenly with respect to the seat, so that the unstable rise of the seat is stable. The sheets can be stacked more reliably. Further, when a plurality of air injection mechanisms 25 are provided, if the control device 11 is set to transmit separate electric signals to the respective air injection mechanisms 25, a more flexible and complicated air injection operation can be performed. realizable. In this way, by performing appropriate control according to the traveling state of the sheet, the sheet stacking unit 20 according to the present embodiment causes the collision between the trailing end of the preceding sheet in the traveling direction and the leading end of the subsequent sheet in the traveling direction. It becomes possible to prevent more reliably, and the sheets conveyed at high speed can be reliably stacked without paper jamming.

  The transport mechanism 30 according to the present embodiment is a mechanism including a shaft member, a roller, a chain, and the like for transporting continuous paper or individual sheets. Inside each unit for conveying continuous paper and between each unit, it is composed of an adjustment roller, a guide roller, and the like, and after being cut into individual sheets, it is composed of a chain, a belt, a vacuum, and the like.

  Next, the operation of the sheet stacking unit 20 used in the printing press 10 according to this embodiment having the above basic configuration will be described with reference to the flowchart of FIG. Here, FIG. 5 is a flowchart showing operations related to the sensor 23, the control device 11, and the air injection mechanism 25 in the sheet stacking unit 20 according to the present embodiment.

  First, the sensor 23 transmits a sheet detection signal to the control device 11 when detecting the trailing end of the conveyed sheet in the traveling direction (step S101).

  The control device 11 that has received the sheet detection signal from the sensor 23 starts counting pulses output from the pulse output machine 24 (step S102).

  The control device 11 determines whether or not the counted number of pulses has exceeded the air injection timing value configured by the ON setting value 42 and the ON adjustment value 44, and when determining that the number has exceeded the air injection timing value, An electric signal is transmitted to the air injection mechanism 25 (step S103). Note that the determination here may determine whether or not the air injection timing value has been exceeded, rather than whether or not the air injection timing value has been exceeded.

  The air injection mechanism 25 that has received the electric signal from the control device 11 opens the electric drive valve by the received electric signal, and starts air injection (step S104).

  On the other hand, in the control device 11, the counting continues even when the number of pulses to be counted exceeds the air injection timing value, and subsequently, the air injection stop timing value composed of the OFF setting value 43 and the OFF adjustment value 45. It is determined whether or not the number is exceeded. When it is determined that the control device 11 has exceeded the air injection stop timing value, the control device 11 transmits an electric signal to the air injection mechanism 25 again (step S105). In addition, you may determine whether the determination here became the same value as the air injection stop timing value instead of whether it exceeded the air injection stop timing value.

  The air injection mechanism 25 receives the electric signal from the control device 11, thereby closing the electric drive valve and stopping the air injection (step S106).

  Then, after determining that the counted number of pulses has exceeded the air injection stop timing value, the control device 11 stops counting the pulses and resets the counted pulses until the trailing edge of the succeeding sheet is detected (step) S107).

  In the sheet stacking unit 20 according to the present embodiment, the above operation is repeated every time a sheet is conveyed. If the distance from the detection position of the sheet to the position where the sheet jumps out of the high-speed conveyance unit 15 is long and the subsequent sheet is detected before the counted number of pulses is reset, the preceding sheet is counted. The number of pulses that have been counted and the number of pulses that have been counted for subsequent sheets may be controlled so as to be counted in parallel. That is, the timing for resetting the counted pulses (step S107) can be arbitrarily changed according to the sheet conveyance state in the sheet stacking unit, the constraint conditions of the equipment, and the like.

  Next, the flow of sheet stacking in the sheet stacking unit 20 according to the present embodiment will be described using the schematic diagram of FIG. FIG. 6 is a schematic diagram showing the flow of sheet stacking in the sheet stacking unit according to this embodiment.

  FIG. 6A shows a state in which the traveling sheet 61 has already passed directly under the sensor 23 and the control device 11 has started counting the number of pulses. From this state, when the rear end of the seat in the traveling direction reaches the air injection position, the air is injected from the air injection mechanism 25, leading as shown in the partial diagram (b) in FIG. The rear end of the traveling direction of the sheet 61 moves to a position below the height when the sheet jumps toward the stacking portion 21. Further, as shown in a partial diagram (c) of FIG. 6, the injection of air from the air injection mechanism 25 is stopped until the leading end in the traveling direction of the subsequent sheet 62 reaches the air injection position. Therefore, the positional relationship between the preceding sheet 61 and the succeeding sheet 62 when the succeeding sheet 62 jumps out toward the stacking unit 21 is as shown in the partial diagram (c) of FIG. The leading end in the traveling direction of the subsequent sheet 62 is positioned higher than the rear end in the traveling direction of 61. That is, the leading end of the subsequent sheet 62 in the traveling direction does not collide with the trailing end of the preceding sheet 61 in the traveling direction, and the sheets can be stacked one after another without any paper discharge error.

  The operation of the sheet stacking unit 20 according to the present embodiment has been described above. The configuration and operation of the sheet stacking unit 20 and the printing press 10 including the sheet stacking unit 20 according to the present embodiment described with reference to FIGS. Not too much. That is, the technical scope of the sheet stacking unit according to the present invention and the printing press including the sheet stacking unit is not limited to the scope described in the above embodiment, and the above described embodiment includes claims. Various changes or improvements can be made within the scope of the description of the range.

  For example, when a solenoid valve is used as an electrically driven valve constituting the air injection mechanism 25, if the solenoid valve is repeatedly opened and closed at a high speed, the sheet cannot be swollen or mechanically unstable. There is a risk of malfunction. In order to solve such a problem, a highly responsive electromagnetic valve may be used as the electrically driven valve. Alternatively, an electropneumatic converter such as a regulator may be used as the air injection mechanism 25. By adopting such an apparatus, even when the sheet conveyance speed is increased, more accurate and complicated control is possible, and stable sheet stacking can be realized.

  As described above, the sheet stacking unit according to the present invention can stably stack sheets under any conditions, and is easy to adjust for stably stacking sheets. To provide a sheet stacking unit that can reduce the work burden due to human jamming and adjustment required when a paper jam occurs, and can stack sheets at high speed without reducing printing efficiency Can do.

  In addition, since the control of air injection is started by using the detection signal of the sensor as a trigger, it is possible to provide a sheet stacking unit that does not need to match the timing of air injection to the sheets to be stacked first. The burden can be reduced.

  Furthermore, since air injection control is triggered by the sensor detection signal as a trigger, there is no need for the operator to adjust the air injection timing to the seat through trial and error. Can be reduced.

  Furthermore, since the amount of air to be injected can be set to a necessary and sufficient amount, the sheets can be appropriately stacked and an energy saving effect can be obtained.

  In addition, it is not necessary to provide all the modified embodiments exemplified above, and it is natural that the present invention also includes a configuration in which each modified embodiment is configured alone or in combination.

  DESCRIPTION OF SYMBOLS 10 Printing machine, 11 Control apparatus, 12 Paper feeding unit, 13 Printing unit, 14 Cutting unit, 15 High-speed conveyance unit, 20 Sheet stacking unit, 21 Stacking part, 22 Butting plate, 23 Sensor, 24 Pulse output machine, 25 Air Injection mechanism, 30 transport mechanism, 41 display unit, 42 ON set value, 43 OFF set value, 44 ON adjustment value, 45 OFF adjustment value.

Claims (6)

A paper feed unit that feeds continuous paper;
A printing unit for printing on continuous paper;
A cutting unit for cutting the printed continuous paper as individual sheets;
A high-speed conveyance unit that conveys the cut sheet;
A sheet stacking unit that releases sheets conveyed at a predetermined position and stacks the sheets on a stacking unit;
A control device for controlling the operation of the sheet stacking unit;
In the sheet stacking unit used in a printing press having:
A sensor for detecting that the front end or the rear end in the running direction of the seat has passed a predetermined position;
A pulse output machine capable of outputting a pulse in accordance with the conveyance state of the conveyed sheet;
An air injection mechanism for injecting air to the sheets when the sheets are stacked on the accumulation section;
With
The sensor is
When it is detected that the leading end or the trailing end of the traveling direction of the sheet has passed a predetermined position, a sheet detection signal is transmitted to the control device,
The control device includes:
In response to a sheet detection signal from the sensor, start counting pulses output by the pulse output machine,
When the counted number of pulses exceeds or is equal to a preset air injection timing value, the air injection mechanism starts air injection,
The sheet stacking unit, wherein when the counted number of pulses exceeds or becomes equal to a preset air injection stop timing value, the air injection mechanism stops air injection. The sheet stacking unit according to claim 1,
The air injection timing value is set by an ON setting value and an ON adjustment value,
The air injection stop timing value is set by an OFF setting value and an OFF adjustment value,
The ON adjustment value and the OFF adjustment value are set as unit values smaller than the ON setting value and the OFF setting value so that the respective values of the ON setting value and the OFF setting value can be finely adjusted. A sheet stacking unit that is set. In the sheet stacking unit according to claim 1 or 2,
The control device detects that the leading end in the traveling direction or the trailing end in the traveling direction of the succeeding sheet has passed a predetermined position after the air ejection mechanism stops ejecting air to the preceding sheet. Until now, the counting of the pulses output by the pulse output device is stopped, and the number of counted pulses is reset. A paper feed unit that feeds continuous paper;
A printing unit for printing on continuous paper;
A cutting unit for cutting the printed continuous paper as individual sheets;
A transport unit for transporting the cut sheet;
A sheet stacking unit that releases sheets conveyed at a predetermined position and stacks the sheets on a stacking unit;
A control device for controlling the operation of the sheet stacking unit;
In a printing press having
The sheet stacking unit includes:
A sensor for detecting that the front end or the rear end in the running direction of the seat has passed a predetermined position;
A pulse output machine capable of outputting a pulse in accordance with the conveyance state of the conveyed sheet;
An air injection mechanism for injecting air to the sheet;
With
The sensor is
When it is detected that the leading end or the trailing end of the traveling direction of the sheet has passed a predetermined position, a sheet detection signal is transmitted to the control device,
The control device includes:
In response to a sheet detection signal from the sensor, start counting pulses output by the pulse output machine,
When the counted number of pulses exceeds or is equal to a preset air injection timing value, the air injection mechanism starts air injection,
A printing machine, wherein when the counted number of pulses exceeds or becomes equal to a preset air injection stop timing value, the air injection mechanism stops air injection. The printing press according to claim 4, wherein
An encoder is used for the pulse output machine, and a pulse is generated by connecting the encoder to a conveyance mechanism for conveying individual sheets cut by the cutting unit. The printing press according to claim 4 or 5,
The printing unit, wherein the conveyance unit is capable of conveying a conveyance speed after cutting a sheet at a speed higher than a conveyance speed before cutting the sheet.

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