JP2002308468A - Method for controlling paper sheet feeding to printing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for controlling paper sheet feeding reduced in cost and improved in operability of a printing machine by again returning to normal operation after an error occurs. SOLUTION: Sensors are arranged in a transport path for a paper sheet 9, and when double-feed of paper sheets 9 is detected by a contact roller 34 and a distance sensor 37 in the course of transporting the paper sheet 9, the state information mDB showing an error is written in a storage device, so the paper sheet 9 causing an error is continuously transported. When the error paper sheet 9 reaches a designated position (front contact 29 position), the state information mDB is evaluated to stop a paper sheet feeder 10. Thus, the error paper sheet is always stopped in a designated position 53 regardless of timing of error detection, the sheet can be easily removed. All paper sheets prior to the error paper sheet 9 are transported as usual and processed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling sheet feeding to a printing press.

[0002]

2. Description of the Related Art It is known to monitor a sheet feed with a detector in a printing press in order to prevent damage to the printing press and inaccurate printing. This detector is arranged in the area of the device for separating the sheets from the pile and / or along the transport path to the printing press. Detectors that operate according to various physical principles have been used, depending on the material and speed of the sheet and the type of paper feed. Examples include a photoelectric detector, a mechanical detector, a capacitance detector, or an ultrasonic detector. The purpose of detection is
If two or more sheets are separated and fed separately, if the length, width or thickness of the sheet is incorrect, or if the sheet is damaged In the case where the corner is bent or the corner is broken, the operation of the separation device and the sheet feeding are stopped as soon as possible. If an incorrect separation or sheet feed is detected by the detector, an appropriate error signal is sent to the control device, which processes the error signal and sends an adjustment signal to the sheet separating device and the transport device. Output to the actuator. For example, the adjustment signal can stop the motor for raising the pile, the air blowing device and the air suction device, and the motor for transporting the sheets from the pile to the printing press.

[0003] Sheets can be fed in various forms which can be set each time by an operator's instruction. In a printing press, the sheets are fed one by one or continuously or partly in a so-called stream-feed operation. In each case, the feeding takes place in synchronism with the printing press cycle, so that the signal from the rotation detector, which represents the printing press cycle, for example, is also processed by the sheet feed control device. . In a simple embodiment, a switch from sheet-by-sheet operation to stream-feed operation is performed by means of a manually operated switch. If the control device has a computer, this switching can be performed by program control, in which case the paper feeding mode to be adopted is inferred from the data of the print job to be processed.

[0004]

Disadvantages of the known method are:
In order to be able to return to normal operation when an error occurs, it is necessary to take out the sheets at various positions according to the sheet feeding mode and the timing at which the separation and the sheet feeding are stopped. Executing sheet removal based on the actual structure is difficult because the sheet guide and the sheet detector are in the way. When removing a sheet, the sheet can be damaged to the point that it can no longer be used. If two overlapping sheets are detected in a stream-feed operation, it is usually processed by the printing press, which is placed in front of the two overlapping sheets after stopping the feeding. All the missing sheets and the two overlapping sheets themselves must be removed. It takes time to restack these sheets.

It is an object of the present invention to provide a method for controlling sheet feeding in which the cost of returning to normal operation is reduced and the operability of the printing press is improved.

[0006]

SUMMARY OF THE INVENTION The object is to provide a method with the features of claim 1 in which the sheet is separated from the pile and fed to a printing press, and the separation or feeding is inaccurate. ,
Or if there is an inappropriate sheet, output a signal by the sheet detector and send the signal to the control device,
A method for controlling sheet feeding to a printing press, in which separation and feeding are stopped to remove overlapping or incorrectly fed or incorrect sheets. Stopping the operation of the sheet feeding device when the sheet to be removed first reaches a predetermined position.
This is achieved by a method for controlling sheet feeding.

[0007] Advantageous embodiments are set out in the dependent claims.

According to the method of the present invention, after detecting improper sheet feeding, one or more sheets detected as inaccurate are always continued by continuing sheet feeding. The paper will be put in place. In a printing press in which the sheet is held in contact with the leading edge stopper before the sheet is delivered to the printing press during normal operation, the sheet that is detected as inaccurate is accurately conveyed to the leading edge stopper. Will be placed in In that case, all sheets which are placed in front of the incorrect sheet are subsequently processed on the printing press. By arranging the sheets in this way after stopping the feeding, inappropriate sheets can be easily removed.

[0009]

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows an offset sheet-fed printing press. This is a four-color satellite printing press having a central cylinder 1 and four printing units 2, 3, 4, 5 around it. Each of the printing units 2 to 5 has a blanket cylinder 6, a plate cylinder 7, and a number of ink unit rollers 8. The sheet feeder 10, the transport gripper 56, and the feed cylinder 11 feed the sheet into the printing unit 2.
５5. Printed sheet 9
Is conveyed onto the pile 13 by the paper discharge device 12.
The paper discharge device 12 has a chain gripper / conveyance device 14. Chain gripper conveyor 14, printing units 2-5, transport gripper 56, and paper feed cylinder 11
Are driven together with a central cylinder 1 connected to a motor 15 via a gear transmission not shown any more. The central body 1 is connected to a rotation detector 16 for detecting a rotation position.

FIG. 2 shows each part of the sheet feeding device 10 in detail. Within the sheet feeder 10 is a sheet pile 17. The sheet 9 is placed on a pile bed 18 and is movable by a motor 19 and a chain drive 20 in a direction 21 perpendicular to the separating device with the suction head 22. The suction head 22 includes a horizontal linear guide 2.
3, and is reciprocally movable to feed the sheet 9 sucked by the suction port 24 onto the paper insertion plate 25.
A pair of transport rollers 26 and 27 are arranged in front of the paper insertion plate 25. The transport roller 26 is fixed, while
The transport roller 27 can swing about a shaft 28.
In order to feed the sheet 9 to the front pad 29, the suction belt 30 wrapped around the directional change rollers 31, 32 is attached to the paper feed plate 25.
Built in. The front rest 29 can be lowered by the operating cylinder 33 below the height of the sheet insert 25 in the direction 34 shown during the processing cycle of the sheet 9.

In order to control the sheet feed, a detector is provided along the transport path of the sheet 9. A contact roller 34, which contacts and rolls on the sheet 9, is provided behind the transport rollers 26, 27 and above the paper feed plate 25. The contact roller 34 slightly swings about a swing shaft 35 according to the thickness of the sheet. The swing lever 36 supporting the contact roller 34 has a two-arm structure, and the second arm has an inductive distance sensor 37 attached thereto. The distance of the distance sensor 37 to the second arm is proportional to the sheet thickness. An ultrasonic detector comprising an ultrasonic transmitter 38 and an ultrasonic receiver 39 is arranged on the conveying path of the sheet 9 and immediately before the front pad 29.
The ultrasonic transmitter 38 emits ultrasonic waves toward the ultrasonic receiver 39 through the opening 40 of the paper insertion plate 25. Depending on the thickness of the sheet material, some of the emitted ultrasonic waves are absorbed. The intensity of the ultrasonic wave in the ultrasonic receiver 39 is a measure indicating the thickness and the number of the sheets 9 through which the ultrasonic wave passes. An optical sensor 41 for monitoring whether the sheet 9 is correctly abutting the front rest 29 is provided directly in the area of the front rest 29.

The conveying roller 26 and the direction changing roller 31 of the suction belt 30 are driven by another motor 42.
As can be seen from FIG. 1, all the motors 15, 19, 42, the working cylinder 33, the rotation detector 16, and the distance sensor 37 are used for the printing operation control including the sheet feeding control.
, The ultrasonic receiver 39 and the optical sensor 41 are connected to the control device 42. Similarly, the operation mode changeover switch 43 is also connected to the control device 42.

The control of sheet feeding will be described below with reference to FIGS.

Before starting printing, the operator operates the operation mode changeover switch 43 in order to determine whether the print job is to be performed one sheet at a time or in a stream feed type operation. Manipulate. A signal used to control the cycle of the printing press and the cycle of the sheet feeding device in accordance with the operation mode is sent to the control device 42 by operating the operation mode switch 43. This means that the position of each sheet 9 can be determined according to the machine angle by using the signal of the rotation detector 16.
By using these detectors, normal sheets,
Information about each sheet 9 as to whether it is a skewed sheet, a double sheet or a premature sheet is derived from the displacement.

FIG. 3 shows a part of a control device 42 used for controlling the sheet feeding apparatus 10. The signals from the rotation detector 16, the distance sensor 37, the ultrasonic receiver 39, and the sheet feed sensor 41 are sent to the feed controller 44. The paper feed controller 44 and the operation unit 45 are connected. If an error occurs, the feed control device 4
4 activates the connecting member 46, the ratchet detent 47 and the sheet stopping member 48. Further, a storage device 49 for sheet information, in which the storage content is periodically changed by the paper feed control device 44, is provided.

FIG. 4 shows the signal processing by the paper feed control device 44 in detail. Storage 49 for sheet information
Are shown along the transport path f of the sheet 9 starting from cycle “1” to cycle “n + 1”. The first sheet 9 is conveyed by the suction head 22 by a first displacement, starting from a rest position 50 on the pile 17. The fact that the sheet 9 is in the first transport section is stored in the storage device 49, and this is indicated by writing "1". In the next paper feed cycle,
The first sheet 9 is transported to the second transport section by the transport rollers 26 and 27 and the suction belt 30. The position information 52.1 of the storage device 49 changes from “1” to “2”. The arrow 51 below the two storage devices 52 indicates that the status information 52.2 relating to the sheet 9 is sequentially sent from the storage device 52 to the storage device 52 in synchronization with the paper feeding cycle. While the first sheet 9 is transported from the transport section “1” to the transport section “2”, the next sheet 9 is transported to the transport section “1”. In the third paper feed cycle, the first sheet 9 is transported from the transport section "2" to the transport section "3", which is indicated by the symbol "3" in the position information 52.1. ing. A contact roller 34,
A device for mechanically controlling the two overlapping sheets is arranged in the transport section “3”. If the sheet 9 in the transport section 3 is a sheet having two overlapping sheets, this is because the contact roller 34 swings upward and the distance sensor 3
7 is detected. The distance sensor 37 sends a signal representing the two overlapped sheets to the paper feed control device 44. The sheet feeding control device 44 writes the state information 52.2 “mDB” in the storage device 52 for the sheet 9. Status information "m
The sheet 9 to which the “DB” has been added is sent to the subsequent transport section “4” to
It is transported to "10". At this time, the position information 52.1 is indexed, and the state information 52.2 of “mDB” is periodically taken over. The sheet 9 reaches the position 53 of the front contact 29 in the transport section “10”. The state information 52.2 is evaluated in step 54 performed in the transport section "10". In the transport section “10”, the sheet 9 is in the state “mD
In the case of "B", an adjustment signal for the connecting member 46, the ratchet detent 47, and the sheet stopping member 48 is generated in the sheet feeding control device 44. By means of the adjustment signal of the connecting member 46, the sheet-feeding member of the sheet-feeding device 10 is mechanically separated from other driving members of the printing press. The other drive members continue to drive the printing press until the sheets 9 already present in the printing units 2 to 5 have been printed and placed on the pile 13. By means of the adjustment signal of the ratchet detent 47, the transport gripper 56 is mechanically locked, ie the transport gripper 56 remains open, and the sheet 9 is moved from the front abutment 29 to the feed cylinder 11. It is not in a state to deliver further. By means of the adjustment signal of the finger-shaped sheet-stopping member 48, the sheet-stopping member 48 is raised in order to prevent the sheet 9 from slipping off when the front pad 29 descends. After all the sheets 9 still present in the printing press have been placed on the pile 13, all the drive members of the printing press stop. The two overlapping sheets 55 are located at the position 53 of the front pad 29 and can be taken out as the topmost sheet 9. For this purpose, the sheet restraining member 48 is released by pressing a button on the operating unit 45.

In a variant of the invention, the signal of the ultrasonic receiver 39 is processed. The ultrasonic receiver 39 operates the transport section “1”.
At "0", it is inspected whether two sheets 9 abutting on the front patch 29 have been fed. This inspection is based on the mechanical angle detected by the rotation detector 16 in the case of the stream feed type operation, and the portion where the sheet 9 partially overlaps the other sheet 9 is determined by the ultrasonic receiver 39. Is performed at a timing that does not exist in the detection area. Ultrasonic receiver 3
When the two overlapping sheets 55 are detected by 9, position information 52.1 of “10” and state information 52.2 of “m / uDB” are given to the sheet 55.
In the same manner as described above for the state information 52.2 of “mDB”, the sheet feeding control device 44
Is stopped, and the user is notified of this by reporting a failure to the operation unit 45. After that, two stacked sheets 5
5 can be taken out as the top sheet 9, which can be easily done when it is in contact with the front pad 29.

Because of the overlap, the signals of both sensors, the distance sensor 37 and the ultrasonic receiver 39, are available. That is, in step 54, “mDB” and “m / u”
The status information 52.2 of "DB" is evaluated. To further increase the certainty, the signal of the sheet feed sensor 41 used for controlling the registration of the feed during the printing operation may be evaluated.

The number and length of the transport sections are determined by a program according to the selection of single sheet operation or stream feed operation, and according to the size of the printed sheets. . The sensors 34, 35, 37, 38, 39
Alignment in the transport direction f so that it can be adapted to different sheet lengths, or the proper unloading location of the incorrectly fed sheet 9 can be adapted to the current situation. It may be possible. The picking place can also be determined by software, and in that case, it is determined in advance in which transport section the feeding of the inappropriate sheet 9 is stopped.

The present invention is not limited to the above-described embodiment relating to a printing press. The invention is applicable essentially to any machine for processing or inspecting sheets. The type of sensor used can be varied according to the material and dimensions of the sheet. For example, multiple sensors may be used across the sheet width, and individual sensors may be used to scan the sheet 9 not only along a scan line but also along a wider path.

[Brief description of the drawings]

FIG. 1 shows a printing press having a sheet feeder.

2 shows the sheet feeder of FIG. 1 during a stream-feed operation.

FIG. 3 is a diagram illustrating a sheet feeding control device.

FIG. 4 is a diagram illustrating signal processing of a sheet feeding control device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Central cylinder 2,3,4,5 Printing unit 6 Blanket cylinder 7 Plate cylinder 8 Ink unit roller 9 Sheet paper 10 Sheet paper feeding device 11 Paper feeding cylinder 12 Discharge device 13 Pile 14 Chain gripper conveying device 15 Motor 16 rotation detector 17 sheet pile 18 pile base plate 19 motor 20 chain transmission device 21 direction 22 suction head 23 linear guide 24 suction port 25 paper insertion plate 26, 27 transport roller 28 axis 29 front contact 30 suction belt 31, 32 Direction change roller 33 Working cylinder 34 Contact roller 35 Swing shaft 36 Swing lever 37 Distance sensor 38 Ultrasonic transmitter 39 Ultrasonic receiver 40 Opening 41 Optical sensor for sheet feeding 42 Motor 42 Control device 43 Operation Mode changeover switch 44 Paper feed control device 45 Operation unit 46 Connecting part 47 Ratchet detent 48 Sheet stopping member 49 Storage device 50 Stationary position 52.1 Position information 52.2 State information 52 Storage device 53 Front contact position 54 Step 55 Two stacked sheets 56 Conveyor grip f Transport direction

 ────────────────────────────────────────────────── ─── Continuation of the front page (71) Applicant 390009232 Kurfuersten-Anlage 52-60, Heidelberg, Federal Republic of Germany (72) Inventor Christopher Bertie Germany 69234 Dealheim Sickinger Strasse 4 (72) Inventor Liner Ihle Germany 69245 Barmenter Le Friederstrasse 11F Term (Reference) 2C250 EB05 EB06 3F048 AA05 AB03 BA12 BA13 BA14 BB02 BB04 BC08 BD08 CA02 DA06 DA07 DB07 DC17 EA03 EA04 EB33 EB39 3F102 AA13 AB03 FA09 EA03

Claims (5)

[Claims] 1. A sheet detector which separates a sheet from a pile and feeds it to a printing press, and if the separation or feeding is incorrect or an inappropriate sheet is present, a sheet detector. And output the signal to the control device, and the two sheets are overlapped.
Or a method of controlling sheet feeding to a printing press, in which separation and feeding are stopped to remove an incorrectly fed sheet or an incorrect sheet, the sheet feeding device ( A method for controlling sheet feeding, wherein the operation of (10) is stopped when a sheet (9) to be taken out first reaches a predetermined position. 2. The method according to claim 1, wherein the sheet (9) is connected to a leading edge stopper (2).
When feeding paper toward 9), the sheet (9) to be taken out is always conveyed to the leading edge stopper (29);
The control method according to claim 1. 3. In the case of periodic sheet feeding, positional information (52.
1) and the state information (52.2) are derived and after a predetermined number of cycles the state information (52.2) is evaluated, at which time the detectors (37, 39) detect incorrect feeding. The control method according to claim 1, wherein upon detection, the sheet feeding device (10) is stopped at a position where the predetermined number of cycles has been reached. 4. A sheet feeding device (1) capable of switching an operation mode from a sheet-by-sheet operation to a partially overlapping sheet feeding.
4. The control method according to claim 3, wherein in the case of 0), the predetermined cycle number is automatically determined according to the operation mode. 5. The storage device (49) of a control device (44) of the paper feeder (10) stores the position information (52.1) and the status information (52.2) relating to the sheet (9). 4. The control method according to claim 3, wherein writing is continuously performed in the step (c).