JPH0541550B2 - - Google Patents

Description

Detailed Description of the Invention [Technical Field of the Invention] The present invention relates to a folding defect inspection device for inspecting folding defects and folding accuracy of signatures folded to a predetermined size by a folding machine connected to a rotary printing press. It is related to.

[Prior art and its problems]

The rotary press is equipped with an in-line triangular plate and a rotary folding machine for printing on paper rolls and then folding the paper into predetermined specifications (size, number of pages, folding method). Ordinary folding machines can be roughly divided into A-size series and B-size series depending on the size of the printing press, and each type of folding machine can produce several types of folds. The machine is adjusted so that each sheet is folded at a predetermined position, but due to poor paper tension, changes in printing press speed, etc., some signatures may not be folded at the correct predetermined position. Therefore, the printing operator needs to inspect each ejected signature each time. However, it is not always the case that defective signatures occur continuously, and they may not be detected immediately, making it difficult to prevent paper loss.Furthermore, if defective folding is discovered, it is necessary to go back and inspect signatures from a long time ago. This results in a loss of time.

Here, an example of a folding machine will be shown, and its function will be explained with reference to FIG. The printed paper is folded in half in the paper flow direction by a triangular plate 15, a nip roller 16, and the like. Then, it is introduced into a folding drum section consisting of an insertion cylinder 17, a catch cylinder 18, and a delivery cylinder 19 of a rotary folding machine. The needle 23 is attached to the insertion barrel 17.
is placed, insert the needle 23 into the front end of the folded sheet, wrap it around the insertion cylinder 17 in the direction of the arrow, and rotate it by a predetermined rotation angle, so that the insertion blade 20 placed on the insertion cylinder 17 and the mouth Mouth 2 located on the trunk 18
The signature is folded at a predetermined folding position by the action of the jaw folder 1, and the signature is conveyed to the jaw barrel 18 side with the folded portion held in the jaw 21. At that time, when it is rotated by a predetermined rotation angle, the cutting blade 24 disposed on the jaw cylinder 18 and the pedestal 25 of the insertion cylinder 17 cut it into a predetermined length. Thereafter, when rotated by a predetermined rotation angle, the jaw cylinder 18 and the delivery cylinder 19 transfer the signature p held in the mouth cylinder 18 to the pawl 22 disposed on the delivery cylinder 19. Thereafter, the claw 22 releases the signature p from the state in which it is held in its mouth at the timing when the signature p is to be introduced into the conveyor belt 5. Thereafter, the signature is conveyed between conveyor belts 5 to a paper discharge impeller. The signatures are received one by one by the impeller 12 and placed on the lower conveyor belt 13. Due to this movement, signatures are continuously produced by the folding machine.

The problem here is the cause of defective signatures, such as misaligned or crooked folding positions folded by the rotary folding machine, but the first cause is changes in the running condition of the paper due to fluctuations in the tension of the paper. In this case, the second cause is the relationship between the jaw 21 and the insert blade 20, which may cause a breakage failure if the jaw 21 and the insert blade 20 are not held parallel.

Conventionally, even when such folding defects occur, the only way to inspect them is to use human eyes, which is very time-consuming and has problems with accuracy.

<Problems to be solved by the invention> The present invention has been made in view of the above-mentioned current situation. One optical sensor is installed in the chopper folding machine, and the edge position is determined over time at the side edge of the signatures being conveyed. The object of the present invention is to provide a folding defect detection device that automatically and accurately detects bends and deviations in signatures by measuring a plurality of times at intervals and using comparison means and determination means.

<Means for Solving the Problems> An outline of the inspection of the folding defect inspection apparatus of the present invention will be explained below with reference to FIGS. 1 and 4. In the inspection device of the present invention, after the signature P has completed the gripping and folding,
The edge position of the side edge of the signature P is measured while it is being conveyed by the conveyor belt 5 to the front stopper 4 at the chopper folding position. As an example, the side of a signature Pa that is being conveyed at the measurement location m on the chopper table 1 near the position of the chopper fold, and the side of the signature Pb that has been conveyed to a position in contact with the front stopper 4 for positioning the chopper fold. Measure the edge position of the end. It is sufficient to measure the edge position at least twice for each signature, but if it is desired to increase the accuracy of the inspection, the measurement may be performed more times. As shown in FIG. 4, the first signature Pa
The edge position of the time side edge Sa and then the time side edge Sb of the signature Pb is detected. When chopper folding is performed at the correct position and orientation, the edge position of the signature P detected at the measurement location m is always constant, and the edge position at this time is used as the reference position for inspection. If a folding defect occurs in which the position of the fold line shifts during the split fold, the signature P is misaligned in a direction parallel to the front surface of the front cover 4 of the split fold, and at this time, the position is detected at the side edges Sa and Sb of the signature P. Both edge positions are different from the reference position. In addition, if a folding defect occurs in which the angle of the fold line is bent during chip folding, the signature P does not completely contact the front cover 4 of the chip folding, and at this time, the signature P is detected at the side edges Sa and Sb of the signature P. One or both of the edge positions differ from the reference position. Therefore, the edge positions of the side edges of the signature obtained in two measurements are each compared with the reference position, and if the difference between the measured edge position of the measured end and the reference position is larger than a certain level, the fold It can be determined that the blade is misaligned or bent. The tolerance between the measured edge position and the reference position varies depending on the accuracy of measurement in the inspection and the quality required of the object to be inspected. In this way, the folding defect inspection device of the present invention measures the edge position of the side edge of the signature conveyed to the chopper folding position multiple times at one location on the chopper table, and calculates each edge position obtained. The presence or absence of folding errors can be determined by comparing with the reference position.

Next, we will discuss the configuration of a folding defect inspection device as an embodiment of the folding defect inspection device of the present invention.
This will be explained using FIG. 3, FIG. 5, and FIG.

The sensor head 11 in FIGS. 2 and 3 is fixed at a position on the chopper table 1 where the edge position of the side edge of the signature P can be measured when the signature P is conveyed to the position where chopper folding is performed. has been done.
If the sensor head 11 can measure the edge position,
A one-dimensional sensor such as an array sensor or a line sensor, or a two-dimensional sensor such as an area sensor or an image sensor may be used. Further, the illumination (not shown) of the sensor head 11 may be of a reflective type or a transmissive type. The inspection of the signature P is performed on all the signatures, and in order to determine the timing for measuring the edge position of the signature in each inspection, timing sensors 31 and 32 are attached to the roller 16 that rotates once per signature, and the conveyance is performed. The timing sensors 31 and 32 are set at a distance from each other for each signature P.
A timing signal is generated every time, and measurement is performed for each timing signal. Timing sensor 31, 32
The mounting position may be any other roller as long as it is a roller that rotates once per signature so that a timing signal can be generated for each signature.

Next, the circuit configuration of the folding defect inspection device of the present invention will be explained based on FIG. 5. Sensor head 11
always operates at a speed sufficient to correspond to the maximum operating speed of the printing press and outputs the video signal V. The edge position detection section 110 detects the edge position of the signature P for each video signal V from the sensor head 11 and always outputs it as a position signal M. When the signature P reaches the conveyed measurement position, the timing sensor 31 first emits the first timing signal Ta, and after an interval, the timing sensor 32 emits the next timing signal Tb. When the timing signals Ta and Tb are issued, the timing control unit 120 simultaneously issues recording signals La and Lb for each of them, and stores the position signals M in the position storage units 130 and 140 when the respective recording signals La and Lb were being output. Make me remember.

In this way, while one signature is being transported, the edge position of the signature side end is measured twice, and the position information obtained from each measurement is stored in the position storage units 130 and 1.
40 and output to comparators 150 and 160 as position signals Ma and Mb, respectively. The reference position setting unit 170 stores the edge position information of the side edge of the signature P when the signature P assumes the correct position and posture during chopper folding, and the reference position signal Ms representing the edge position is used as the reference. It is output from the position setting section 170. The setting of the reference position in the reference position setting section 170 may be determined based on the position detected by the sensor head 11 and the edge position detection section 110 during normal chopper folding, or may be determined based on the position detected by the sensor head 11 and the edge position detection section 110 during normal chopper folding, or may be determined by multiple detections. It may be determined based on an average of the positions, or may be determined in any manner by appropriate processing or manipulation. The reference position signal Ms is input to comparators 150 and 160, and the comparator 150 outputs the position signal Ma and the comparator 16.
If it is 0, it is compared with the position signal Mb. Comparator 15
0 and 160 respectively detect the difference between the positions indicated by the two input signals and output the difference signals Da and Db to the determiner 180,
190. The judgment devices 180 and 190 store threshold values that are the allowable range amount of the difference between the edge position and the reference position obtained by measurements that are acceptable for normal signatures, and the difference represented by the difference signals Da and Db is within the allowable range. If the quantity is exceeded, it is determined that the inspected fold is defective, and defect signals Ea and Eb are output.

Here, the threshold value, which is the allowable range amount, is variable and may be set to an arbitrary amount depending on the inspection accuracy, quality requirements for the inspection object, etc.

After emitting recording signals La and Lb according to the timing signals Ta and Tb from the timing sensors 31 and 32 to measure the edge position, the timing control section 12
0 outputs the display signal F to the defective display unit 200 upon completion of the determination operation in the determiners 180 and 190. The defect display unit 200 checks whether the defect signals Ea and Eb are output from the determiners 180 and 190 at the time when the display signal F is input, and displays the result of the inspection.

The defect display unit 200 may notify the printing press operator of the inspection results by turning on a buzzer or lamp, or may display the type and number of defects, or generate an information signal to notify the printing press operator of the inspection result. Feedback may be applied to the adjustment control part of the folding machine so that it can be used for automatic adjustment of the folding machine.

〔Effect of the invention〕

As described above, according to the folding defect inspection device of the present invention, folding defects can be easily detected by the simple measurement of edge position detection using only one sensor at the edge of the signature and by the process that can be implemented with any device. It is possible to detect the occurrence of printing, and it can exhibit excellent effects such as stabilizing the quality of printed matter and reducing paper waste.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention.
The figure is an explanatory plan view showing the measurement location at the folding position of the folding defect inspection device of the present invention.
3 is an explanatory view of the appearance of an example of an inspection device for specifically carrying out the folding defect inspection device of the present invention, showing the sensor head and the mounting position of the timing sensor, and FIG. FIG. 5 is an explanatory plan view showing the position of the edge on the edge, and FIG. 5 is a block diagram showing an example of the overall configuration of the folding defect inspection apparatus of the present invention. 1: Chopper table, 4: Front plate, 5: Conveyor belt, 11: Sensor head, 31, 32...
Timing sensor, 110... Edge position detection section, 120... Timing control section, 130, 14
0...Position storage unit, 150, 160...Comparator,
170...Reference position setting section, 180, 190...
Judgment device, 200...Failure indicator, 100...Folding defect inspection device, 2...Chopper folding machine.

Claims (1)

[Claims] 1. In the chopper folding machine connected to the rear part of the folding machine of a rotary printing press, place the signature in a position where the side edges of the signatures that are being moved can be detected so that the chopper table surface faces the front support and the front edge comes into contact with the folding machine. An edge position detection unit is provided with an optical sensor such as a line sensor or an image sensor that measures the positional fluctuation of the side edge, and an edge position detection unit that inputs the detection signal from the sensor and outputs a position signal M. a timing sensor that emits a number of measurement timing signals corresponding to the number of times n of side edge position measurements for the side edge of the frame at certain time intervals; and a timing sensor that inputs the measurement timing signals from the timing sensor and records them at the time intervals. Measuring means comprising a timing control section for emitting a signal, a respective position storage section for inputting the respective recording signal and recording the position signal M when the signal was being output, and each of the memorized positions. Signal M and a reference position signal from a preset reference position setting section
Comparing means each having a comparator that compares the difference signal with M _s and generating a difference signal, and determining means comprising a determining device that receives the difference signal and generates a defect signal E when the difference signal exceeds a preset allowable threshold. A folding defect inspection device characterized in that the folding defect inspection device is provided with a defect indicator and outputs the result of the determination on a defect indicator.