JPH0378066B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a non-feed detection device in a printing press, and more specifically, to a non-feed detection device for a printing press. The present invention relates to a non-feed detection device in a printing press that detects and outputs a non-feed.

(Prior art) In a printing machine, when printing paper does not feed, it is thought that some kind of trouble has occurred in the paper feed section, so it is necessary to take immediate action after detecting the non-feeding. .

The following measures can be considered for this.

Stop the coining operation.

Stop the transfer operation.

Stop paper feeding operation.

Stop ink supply operation.

In reality, it is possible to consider a combination of several of these measures after detection of non-feed.

On the other hand, in conventional printing presses, processing after non-feed printing and non-feed detection were performed as follows.

FIGS. 2 and 3 are diagrams for explaining a non-feed detection device in a conventional printing press. Note that FIG. 2 is a view seen from the operating side, and FIG. 3 is a view seen from the opposite side to FIG. 2.

As shown in Figure 2, the printing process involves the function of rotating the printing press, the ink supplied via the ink font roller, ink duct roller, filtration roller, and rider roller, the water font roller, and the water duct roller. A function that balances the dampening liquid supplied through the plate cylinder with a vibrating roller, a form roller, etc., and inks the plate wrapped around the plate cylinder. The function of transferring the ink on the blanket cylinder to the blanket cylinder, and the function of coining the image on the blanket cylinder with the impression cylinder are required.

As shown in FIG. 3, in the conventional printing machine, paper 10 is placed between a first paper feed roller 11 and a second paper feed roller 1.
Paper feeding was detected by pushing a paper feeding lever 13 provided between the two. By the movement of this lever 13, transfer and coining are mechanically performed for each fed sheet. Note that 14 is an upper guide, 15 is a lower guide, and 16 is a spring.

In such a printing machine, when a non-feed occurs, paper feeding is not detected, so only the transfer and coining operations are stopped for one rotation. Therefore,
When the next sheet is fed normally, the transfer and coining operations are restarted. These transfer and coining operations are not performed immediately upon paper feeding detection, but are started at timings determined by cam operations. Further, when a non-feed occurs or when paper feeding ends, the transfer and coining operations are canceled at a timing determined by the operation of the cam. When normal paper feeding continues, transfer and coining operations are also performed continuously.

(Problems to be Solved by the Invention) As described above, in conventional printing presses, the paper feeding detection mechanism was basically used for detecting non-feeding without the purpose of detecting non-feeding. That is, basically, the purpose is not to detect non-feeding, but to detect paper feeding, and it can also be applied to detect non-feeding as a function opposite to paper feeding detection.
Therefore, it is not suitable for original paper feeding detection.

In addition to the above-mentioned measures, there are other methods to take after detecting non-feeding, such as stopping paper feeding and stopping ink supply, so for this purpose it is more advantageous to detect non-feeding electrically. However, in conventional printing presses, detection is performed using purely mechanical operations, which is not suitable for obtaining electrical signals. In order to obtain electrical signals from such a printing machine, in addition to the conventional mechanism, means for detecting whether inking operation is in progress or paper feeding operation is in progress is provided, and the movement of the paper feed detection lever and detection means are added. A means to detect timing is required. As the automation of printing presses progresses, the need to electrically detect the status of the printing press increases, so electrical detection is more advantageous from this point of view as well.

Furthermore, with conventional printing machines, when a misfeed occurs,
There was no appropriate means to issue a warning to that effect.

An object of the present invention is to electrically detect and output that paper is not being fed from the paper feed section to the printing cylinder at the regular timing during printing, and to detect non-feeding in a printing press that solves all of the above-mentioned problems. The goal is to provide equipment.

(Means for Solving the Problems) In order to achieve the above object, a non-feed detection device for a printing press according to the present invention includes a timing pulse generator that generates a timing pulse synchronized with the rotation of a printing cylinder during printing; a paper feed detector that detects the supply of paper from the paper feed section to the printing cylinder and outputs a paper feed detection signal; and a paper feed detector that counts the timing pulses and outputs a count signal that is reset by the paper feed detection signal. a counter that outputs a set value of the rotation angle of the printing cylinder that determines that the paper feeding unit is in a state where the paper is not fed; It is comprised of a comparator that outputs a feed detection signal, and a non-feed memory circuit that generates and outputs a non-feed memory signal from the paper feed detection signal, and whose memory is erased by the paper feed detection signal.

(Example) Hereinafter, the present invention will be described in detail with reference to the drawings and the like.

FIG. 1 is a block diagram showing an embodiment of a non-feed detection device for a printing press according to the present invention.

The timing pulse generator 1 generates timing pulses corresponding to the rotation of the printing cylinder, and uses a photosensor to generate timing pulses synchronized with a slit in a rotating disk provided on the printing cylinder. The timing pulse generated by the timing pulse generator 1 is sent to the clock terminal of the counter 4.
Connected to CL.

The paper feed detector 2 is for detecting that paper is being fed and outputting a paper feed detection signal. A photoelectric sensor using an LED and a phototransistor is used for this purpose. The paper feed detector 2 is provided on the paper supply path from the paper feed section to the printing cylinder. The output of the paper feed detector 2 is connected to a reset terminal R of a counter 4 via a one-shot multivibrator (hereinafter referred to as OSM) 3.

The counter 4 counts and outputs the timing pulses generated by the timing pulse generator 1 as a printing cylinder rotation signal. The counter 4 is reset by a paper feed detection signal from the paper feed detector 2. In other words, the counter 4 counts the angle at which the printing cylinder rotates while the paper is not being fed.

The outputs of the counter 4 and the setting storage section 6 are connected to the comparator 5 . Comparator 5 compares the output of counter 4 and the output of setting storage section 6, and outputs a match signal when they match. This coincidence signal becomes a non-feed detection signal. The output of the comparator 5 is connected to a non-send storage circuit 7.

The setting storage unit 6 stores a reference value of the number of revolutions of the printing cylinder at which it is determined that the paper feed unit has not fed the paper.

The non-send storage circuit 7 is a circuit that generates and outputs a non-send storage signal based on the match signal from the comparator 5. In the non-feed memory circuit 7, the non-feed memory signal is erased by the paper feed detection signal from the paper feed detector 2.

The alarm device 6 is for generating an alarm indicating non-feeding when the non-feeding storage circuit 7 outputs an output. For example, it may be displayed visually using an LED or the like, or it may be alarmed audibly using a buzzer or the like. Of course, these means can also be used together.

Next, the operation of the non-feed detection device according to the present invention will be explained using a specific example.

It is assumed that the timing pulse generator 1 generates "36" pulses per rotation of the printing cylinder. On the other hand, the setting storage unit 6 stores "37" as the number of pulses.

If paper is being fed normally, counter 4 will be “35”
It is reset to "0" by the paper feed detection signal from the paper feed detector 2.

When non-feeding occurs, even if the counter 4 counts up to "35", it is not reset because there is no paper feed detection signal from the paper feed detector 2, and it continues to count up to "37". At this time, since the output of the counter 4 matches the set value of the setting storage section 6, the comparator 5 outputs a match signal.

Based on the match signal from the comparator 5, the non-feed storage circuit 7 generates a non-feed storage signal and outputs it to the alarm 8, and the alarm 8 issues an alarm to that effect.

If the non-feeding occurs only once and the next paper feeding is performed normally, the paper feed detector 2 detects the paper feeding and erases the non-feeding memory signal in the non-feeding memory circuit 7.

(Modification) In this embodiment, there is no special regulation on the timing of the timing sensor, and if a timing sensor for another purpose is used, it can be used in common. In particular, such timing sensors are always used in automated printing machines that use microcomputers, so the counters and comparators used in this device can be replaced with additional components by using the same functions in the CPU. The invention can be practiced without.

In addition, we have described an example in which an alarm is installed, but as mentioned above, there are several ways to take action after detecting non-feed, so we recommend a mechanism that uses solenoids to stop ink supply, paper feed, etc. If provided, it is easy to use the present invention to operate those solenoids instead of the alarm to perform the respective measures.

Further, as an application example of the present invention, the non-feed detection signal which is the output of the comparator 5 is counted by a newly provided counter, and this counter is reset by the paper feed detection signal from the paper feed detector 2. By this, the counter counts the number of consecutive non-feeding detections, and when this exceeds a certain value,
Applications such as stopping the paper feeding operation are also possible.

Furthermore, according to the present invention, a buzzer is used to warn when a non-feed occurs, and if the next paper feeding is performed normally, the buzzer is stopped and printing continues, and only when non-feed continues, the buzzer is activated. You can also stop the paper movement.

In addition to this, according to the present invention, it is easily possible to combine several measures after detection of non-feeding.

(Effects of the Invention) As explained in detail above, according to the present invention,
It is possible to detect that paper is not being fed from the paper feed section to the printing cylinder at the proper timing during printing, and to detect that the paper feed mechanism of the paper feed section has not fed the paper.

In addition, in a device that detects non-feeding based on the timing of a single point on the printing cylinder, if the timing detector is synchronized with the plate cylinder or blanket cylinder, this timing must be changed when the vertical adjustment is made. However, in the apparatus according to the present invention, if the rotation angle of the printing cylinder is set in advance by taking into account the vertical adjustment, there is no need to change the timing.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of a non-feed detection device for a printing press according to the present invention. FIGS. 2 and 3 are diagrams for explaining a non-feed detection device in a conventional printing press. 1...Timing pulse generator, 2...Paper feed detector, 3...OSM, 4...Counter, 5...Comparator, 6
...setting memory section, 7...non-feeding memory circuit, 8...alarm device.

Claims (1)

[Claims] 1. A timing pulse generator that generates a timing pulse synchronized with the rotation of the printing cylinder during printing, and a paper feed detector that detects the supply of paper from the paper feed section to the printing cylinder and outputs a paper feed detection signal. , a counter that counts the timing pulses and outputs a count signal, and is reset by the paper feed detection signal, and a set value for the rotation angle of the print cylinder that determines that the paper feed section is not feeding the paper. a comparator that outputs a non-feed detection signal when the count signal becomes equal to the set value; and a comparator that generates and outputs a non-feed storage signal from the non-feed detection signal, and A non-feed detection device for a printing press comprising a non-feed memory circuit whose memory is erased by a paper detection signal.