JPH0213907B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for automatically detecting abnormal printing such as cylinder printing and deprinting in a sheet-fed rotary printing press.

A sheet-fed rotary printing press is equipped with printing cylinders such as an impression cylinder, a blanket cylinder, and an intaglio cylinder.When paper is fed between the impression cylinder and the blanket cylinder and between the impression cylinder and the intaglio cylinder, Only in this case, printing pressure is applied between each cylinder to print the pattern on the paper, and once the paper passes through each cylinder as it rotates, the printing pressure is removed. It is supposed to be used to remove the body.

For this reason, if paper is inserted correctly only when paper is interposed between the impression cylinder and the blanket cylinder or between the impression cylinder and the intaglio cylinder, problems will not occur, but in large printing machines Since the control of cylinder insertion and copper removal is performed by a hydraulic mechanism, errors may occur in the timing of cylinder insertion or cylinder removal due to changes in the operating speed or operating load of the printing press, causing problems with the impression cylinder. This results in cylindrical printing to which printing ink adheres, or non-printing in which the paper is not printed at all, or semi-printing in which the paper is only partially printed.

Therefore, in deprinting or semi-deprinting, it is necessary to treat the paper as defective, while in cylinder printing, the back side of the paper is smudged by ink adhering to the impression cylinder, so the impression cylinder must be cleaned. It becomes a thing,
There is a need to detect these abnormal printings, but conventionally, abnormal printing was monitored visually, which made it difficult to detect abnormal printing, causing delays in taking countermeasures, and slowing down operations. This has resulted in drawbacks such as increased mental burden on employees.

The purpose of the present invention is to fundamentally solve such drawbacks of the conventional art, and it detects the insertion of the printing cylinder with a cylinder insertion detector, and detects the paper that has passed through the printing cylinder with a paper detector. An extremely effective system that automatically detects the presence or absence of abnormal printing based on the detection force and sends out signals indicating cylinder printing and off-printing.
The present invention provides an abnormal printing detection device for a sheet-fed rotary printing press.

Hereinafter, details of the present invention will be explained with reference to figures showing examples.

FIG. 1 is a schematic side view of a dry offset intaglio printing machine showing an example of a sheet-fed rotary printing machine. Paper 2 fed from a feeder section 1 is fed onto a feeder board 3. The position is regulated by a front stop (not shown in the figure) provided at the tip of the paper, and the paper is passed between the first paper transfer cylinder 5 and the second paper transfer cylinder 6 by the swing claw of the swing device 4. The sheet is then further transferred to the impression cylinder pawl of the impression cylinder 7, and after being printed by the blanket cylinder 8 and the intaglio cylinder 9, it is conveyed by the pawl rod of the sheet discharge belt 10,
It is designed to be discharged to the first pile 11a or the second pile 11b of the delivery section 11.

Further, a number cylinder 12 having numbering is provided opposite to the second paper transfer cylinder 6, whereby
A management number is printed on the surface opposite to the surface printed by the blanket cylinder 8 and the intaglio cylinder 9.

In addition, 13a to 13d are dry plate cylinders that transfer the pattern to the blanket cylinder 8, and 14a to 14c
is an intaglio cylinder that transfers ink to the intaglio cylinder 9 according to the pattern, and in a corresponding relationship, the impression cylinder 7, rubber cylinder 8, and intaglio cylinder 9 transfer ink to the intaglio cylinder 9 in accordance with the pattern. It has a quadruple cylinder that can print.

A photoelectric paper detector PPD that receives transmitted light is provided near the impression cylinder 7 side of the paper discharge belt 10, and detects the presence or absence of the paper 2 that has passed through the printing cylinders 7 to 9. are doing.

FIG. 2 shows the configuration of a body insertion detector used for detecting body insertion.
A proximity switch 27 is provided to face the actuator 26 of the hydraulic cylinder 25 which is rotated in the direction of the arrow through the actuator 26 via the actuator 26.
When the object protrudes in the direction of the body insertion DI, the head of the object is detected by the proximity switch 27.

The parts shown in FIG. 2 are of what is known as a "copper-filled device using an eccentric."

FIG. 3 is a block diagram showing a pulse generator for generating synchronizing pulses according to the operation of the printing press, and includes a cam plate 31 as a proximal body connected to one of the printing cylinders 7 to 9. In addition, a proximity switch 33 is provided opposite the protrusion 32 of this, and as the cam plate 31 rotates, the switch 33 is directly activated.
The synchronization pulse is extracted from the

Therefore, according to the configuration shown in FIG. 3, a number of synchronization pulses equal to the number of printed sheets can be obtained in response to one rotation of the printing cylinders 7 to 9 for printing four patterns.

Figure 4 shows each cylinder 5, 6, 12, 13a to 13d, 14a to 14c, where one rotation corresponds to one pattern.
This is a configuration diagram of a pulse generator used for extracting synchronizing pulses from the above, in which only a series of protrusions 32 are provided on a cam plate 31, and a proximity switch 33 is provided opposite to this.

Therefore, in this case as well, a number of synchronization pulses equal to the number of printed sheets can be obtained.

Figure 5 is a block diagram of the electric circuit, Figures 6 to 9.
The figure is a timing chart showing the waveforms of each part in FIG. is not sent.

That is, in FIG. 5, only the detected force (a) of the body insertion detector DID that is synchronized with the synchronizing pulse (c) from the pulse generator PG passes through the AND gate _G1 , and the signal (d) is applied to the shift register SR ₁ , and in this shift register SR ₁ it is shifted according to the situation until the paper 2 is transferred to the paper detector PPD in accordance with the synchronization pulse (c).
It is given as a signal (g) to AND gate _G2 . AND gate G ₂ as a gate circuit has a paper detector
A signal (i) obtained by inverting the detected power (f) of the PPD from the inverter IN ₁ and a synchronizing pulse (c) are given, and in this AND gate G ₂ , the detected power ( Signal (g) obtained by shifting a) and paper detector
A match is made with the signal (i) obtained by inverting the detection power (f) of the PPD.

In addition, the detected force (a) of the body insertion detector DID is inverted by inverter IN ₂ , and then ANDed as a signal (d).
Only the signal synchronized with the synchronization pulse (c) passes through the AND gate _G3 , and _the signal
(e) and is given to shift register SR ₂ , and in this shift register SR ₂ , the synchronization pulse is
After being shifted according to the situation until the paper 2 is transferred to the paper detector PPD according to (c), AND
It is given as a signal (h) to gate _G4 . AND gate G ₄ as gate circuit has paper detector PPD
The detection force (f) and synchronization pulse (c) are given, and in this AND gate _G4 , the detection force (f) and the synchronization pulse (c) are given.
A signal (h) obtained by shifting the inverted signal (b) of the detection force (a) of the DID is matched with the detection force (f) of the paper detector PPD.

In other words, the output (g) of shift register SR ₁ , the synchronization pulse (c) and the inverted output (i) of inverter IN ₁ are
AND gate _G2 , and the coincidence of these produces a signal (j) indicating cylinder printing, that is, a signal Sd indicating cylinder printing, and in the case of Fig. 6. is the output (g), synchronous pulse (c)
and the timing of the inverted output (i) do not match, and the signal
Sd will not occur. Also, the output of shift register SR ₂ (h), synchronization pulse (c) and paper detector
The detection power (f) of PPD is given to AND gate G ₄ ,
The coincidence of these produces a signal (k) indicating off-printing, that is, a signal Sr indicating off-printing. In the case of FIG. 6, the output (h),
The timings of the synchronization pulse (c) and the detection force (f) do not match, and the signal Sr is not generated.

Fig. 7 shows a case where the timing of removing the trunk is delayed; in contrast to the normal state shown by the chain line in Fig. 7a, if the detected force (a) as shown by the solid line occurs, If the detection force of the body insertion detector DID becomes "L" level at the X point shown in the figure a because the withdrawal timing is late, the phase relationship with the synchronizing pulse (c) will be as shown in the figure. As a relation, illustrated
X At _one point, synchronization pulse (c), shift register
Output of SR ₁ (g) and inverted output of inverter IN ₁ (i)
match, so the "H" level signal indicating cylinder printing
Sd is now sent out from AND gate _G2 .
That is, if the shell removal is delayed at point X in FIG. 7, a signal with a time width τ ₁ indicating the shell insertion state will be generated at the output (d) of the AND gate _G1 . This signal with a time width τ ₁ corresponds to the situation in which the paper 2 is transferred to the paper detector PPD, and the signal has a time width of 4 in the synchronization pulse (c).
It appears as the output of shift register SR ₁ at the shift point (X ₁ point shown in g in the figure). At this time,
Since the detection force (f) of the paper detector PPD is at the "L" level and the paper 2 is not detected (because the output (i) of the inverter IN ₁ is at the "H" level), AND All three inputs of gate _G2 are at "H" level and match, and due to these matches, the AND
As shown in FIG. _2J , a signal Sd at the "H" level indicating the body plate is transmitted from the gate G2.

In addition, in FIG. 7 shown above, the cylinder printing that occurs when the timing of cylinder removal is delayed has been described, but the cylinder printing that occurs due to the paper falling off can also be handled by the signal sent from the AND gate _G2 . It is possible to detect based on Sd. That is, if the detection force of the paper detector PPD that should normally appear as shown by the dashed line in the figure does not appear at point W shown in FIG. 8f, it can be determined that the paper has fallen off. At this time, the output (g) of shift register SR ₁ becomes "H" level, which confirms the fact that the paper has fallen out and entered the barrel state.
All three inputs of AND gate _G2 become "H" level and match, and due to these matches, the AND gate
From G ₂ , as shown in j of the same figure, "H" indicating cylinder printing
A level signal Sd is now sent out.

In other words, when the printing cylinders 7 to 9 are inserted, if the paper 2 is not fed between them, the paper detector
Paper 2 is not detected at the time of PPD detection, and the detection power of the paper detector PPD is “L”.
(low level), and the output of the inverter _IN1 becomes "H" (high level), so that the output of the AND gate _G2 also becomes "H", and this is output as the signal Sd indicating cylinder printing.

Fig. 9 shows a case where the timing of the trunk insertion is late; in contrast to the normal state shown by the chain line in Fig. 9a, if the detected force (a) as shown by the solid line occurs, that is, the trunk If the detection force of the body insertion detector DID reaches the "H" level at point Y shown in figure a because the input timing is late, the positional relationship with the synchronizing pulse (c) will be as shown in the figure. As a relation, illustrated
Y At _one point, synchronization pulse (c), shift register
Since the output (h) of SR ₂ and the detection force (f) of the paper detector PPD match, there is a "H" level signal indicating off-printing.
Sr is now sent out from AND gate _G4 .
That is, if the trunk insertion is delayed at point Y in FIG. 9, a signal with a time width of τ ₂ indicating the trunk removal state will be generated at the output (e) of the AND gate _G3 . This signal with a time width τ ₂ corresponds to the situation in which the paper 2 is transferred to the paper detector PPD, and the signal has a time width of 4 of the synchronization pulse (c).
It appears as the output of shift register SR ₂ at the shift point (Y ₁ point shown in h in the figure). At this time,
Since the detection force (f) of the paper detector PPD is at the "H" level and the paper 2 is being detected,
All three inputs of AND gate _G4 become "H" level and match, and due to these matches, the AND gate
From G ₄ , as shown in k in the same figure, "H" indicates off-printing.
A level signal Sr will now be sent.

In other words, if the paper 2 is fed between the printing cylinders 7 to 9 at the time of cylinder removal, the paper 2 will be detected at the time of detection by the paper detector PPD, and this detection force will be "H". , the output of AND gate _G4 also becomes "H", and this is sent out as a signal Sr indicating unprinting.

Therefore, cylinder printing due to the absence of the paper 2 at the time of cylinder insertion and unprinting due to the presence of the paper 2 at the time of cylinder removal are detected, and the normally printed paper 2
Countermeasures such as discharging the paper 2 onto the first pile 11a and discharging the paper 2 on which abnormal printing has been performed to the second pile 11b can be automatically taken in response to the signals Sd and Sr.

However, the detection of paper 2 by the paper detector PPD is as follows:
When detecting half-printing, it is desirable to detect it at the head and tail of the paper 2, and either two paper detectors PPD are provided, or a synchronous pulse is generated twice for one pattern. It is suitable if

In addition, in FIG. 5, a reset circuit RS such as a reset switch is provided, by which the shift registers SR ₁ and SR ₂ can be reset to set their initial states.

In addition, the installation position of the paper detector PPD can be determined depending on the situation, and AND gates G ₂ and G ₄ can be installed.
The same applies to NAND gates, etc., and the present invention can be freely modified in various ways.

As is clear from the above explanation, according to the present invention, cylinder printing and unprinting are automatically detected, and it is optional to automate countermeasure processing for these, thereby realizing labor saving and reliable detection of abnormal printing. However, remarkable effects can be obtained in various sheet-fed rotary printing presses.

[Brief explanation of drawings]

The figures show an embodiment of the present invention, Fig. 1 is a schematic side view of a dry offset intaglio printing machine, Fig. 2 is a diagram showing the configuration of a cylinder insertion detector, and Figs. 3 and 4 are a pulse generator. FIG. 5 is a block diagram of an electric circuit, and FIGS. 6 to 9 are timing charts showing waveforms of various parts in FIG. 2...Paper, 7...Impression cylinder, 8...Rubber cylinder, 9...
... Intaglio cylinder, 25 ... Hydraulic cylinder, 26 ... Actuator, 27, 33 ... Proximity switch, 31
...Cam plate, 32...Protrusion, DID...Body insertion detector, PPD...Paper detector, PG...Pulse generator,
_SR1 , _SR2 ...Shift register, _G1 ~ _G4 ...
AND gate, Sd, Sr...signal.

Claims (1)

[Claims] 1. In a sheet-fed rotary printing press that inserts a printing cylinder in accordance with the supply of paper, a cylinder insertion detector that detects the insertion of the printing cylinder and a pulse that generates a synchronization pulse according to the operation of the printing press. a generator, a paper detector that detects the paper that has passed through the printing cylinder, a first gate circuit that allows only the detected force of the cylinder entry detector that is synchronized with the synchronization pulse to pass; a first shift register that shifts the passing output of the first gate circuit in response to the synchronization pulse according to the situation until the paper is transferred to the paper detector; and a shift output of the first shift register. and a second gate circuit that outputs a signal indicative of cylinder printing by reversing the detection force of the paper detector, and a second gate circuit that inverts the detection force of the paper detector. a third gate circuit that passes only the inversion detection force that is synchronized with the synchronization pulse, and the passage output of the third gate circuit is transmitted to the paper detector according to the synchronization pulse; A second shift register that shifts according to the situation until the paper is transferred to a second shift register, and a signal indicating unprinting is sent by matching the shift output of this second shift register with the detection force of the paper detector. What is claimed is: 1. An abnormal printing detection device for a sheet-fed rotary printing press, characterized in that a fourth gate circuit is provided.