JPH0244713B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a paper jam detection device for a web rotary printing press. In general, in roll-fed rotary printing machines, if the cut and folded printing paper (signature) jams during the process, not only will the product become defective, but the paper that follows at high speed will instantly cause the belt to jam. This may result in cutting or damage to the machine. For this reason, a paper jam detection device is provided which detects a paper jam, stops the web rotary printing press (hereinafter referred to as the printing press), and issues an alarm. In this type of paper jam detection device, there are two types of paper jam detection devices: one that uses optical means to detect paper jams, and the other that detects paper jams by installing a limit switch at a position where paper jams are likely to occur. In the latter detection device using a limit switch,
If the limit switch is installed too low, incorrect detection will occur due to paper jams, etc. If it is installed too high, it will not be detected unless there is a large amount of paper jammed, making it difficult to select the setting position. At the same time, too much contact with paper may cause problems such as staining of the printed surface, and in extreme cases, the limit switch may be damaged. For this reason,
Optical detection means are widely used. As an example of a conventional paper jam detection device using this optical means, a photoelectric detector for signatures passing through the signature conveyance path is provided, and the printing machine is activated based on the output of this photoelectric detector. Paper present and paper absent inspection signals are performed with narrow pulse width paper present and paper absent inspection signals synchronized with the feed cycle of signatures taken out from the rotating part using a proximity switch etc., and the paper present inspection signal is detected. A paper jam detection signal is generated if the output of the photoelectric detector is a detection output indicating that there is no paper at the timing, or if the output of the photoelectric detector is a detection output indicating that paper is present at the timing of the paper-out test signal. There is something I did. However, when the output of the photoelectric detector is inspected at certain inspection timings, if the proximity switch that outputs the inspection signal fails, no inspection signal is output, so even if there is a paper jam, the paper jam cannot be detected. The drawback was that no signal was output. At the same time, since the paper presence inspection signal and the paper absence inspection signal are set to narrow pulse signals, there is a drawback that malfunctions occur due to noise. In addition, two sets of proximity switches are required to generate a paper presence inspection signal and a paper absence inspection signal, which increases maintenance and material costs and imposes space constraints. Furthermore, it is necessary to determine the timing of the paper presence inspection signal and paperless inspection signal in accordance with the timing of the passage of signatures, but since the timing of passage of signatures is slightly different between high speed and low speed, the inspection timing setting is difficult. It had drawbacks such as being troublesome. Therefore, the present invention has been made to solve the above-mentioned drawbacks of the conventional paper jam detection device, and its purpose is to provide a simple structure, low cost, and a device that does not malfunction due to noise or the like. It is an object of the present invention to provide a paper jam detection device for a rolled paper rotary printing press that can reliably detect paper jams. In order to achieve such an object, the paper jam detection device for a rolled paper rotary printing press according to the present invention compares signals generated at the same timing from two signature detection circuits arranged in series after the folding drum. A paper presence determination circuit that outputs a paper presence signal when there is a signature at one signature detector setting position, and a paper out determination circuit that outputs a paper out signal when there is no signature at one signature detector position. The paper jam is determined to be a paper jam when an output is generated from any of the circuits for a predetermined period of time or more. Hereinafter, the present invention will be explained in detail using the drawings. FIG. 1 is a circuit diagram showing an embodiment of a paper jam detection device for a web-fed rotary printing press according to the present invention.
This is a case where the interval between two sets of signature detectors arranged in series on the signature conveyance path corresponds to one page of signatures. In the figure, reference numerals 1 and 2 are photoelectric signature detectors arranged in series on the signature conveyance path and consisting of a light emitter and a light receiver for detecting signatures passing through the signature conveyance path. Ding detector 1 and 2
The installation interval l corresponds to one page of the signature. 3
is a paper jam detection system that outputs a paper jam detection signal when the detection signals A and B output from signature detectors 1 and 2 respectively have the same phase relationship and the phase shift exceeds a predetermined width. and an AND gate 3a which is a circuit and outputs a paper presence determination signal C by detecting the presence of a signature when there should not be a signature on the signature conveyance path at the set position of one of the signature detectors; , a NOAH gate 3b detects that there is no signature on the signature conveyance path at the signature detector setting position when there should be a signature, and outputs it as a paper-out determination signal D, and an AND gate 3a outputs it. an OR gate 3c which OR-inputs a paper presence determination signal C and a paper out determination signal D output from the NOR gate 3b and outputs the output as a paper jam determination signal E; and a paper jam determination signal E output from the OR gate 3c. and a delay circuit 3d that outputs the output as a paper jam detection signal F only when the pulse signal exceeds a predetermined width τ, and an AND gate 3.
The circuit consisting of a, NOR gate 3b, and OR gate 3c outputs a signal corresponding to the phase shift when two input signals have the same phase relationship, as shown in the truth table in Table 1 below. It constitutes a matching circuit.

[Table] FIG. 2 is a diagram showing the mounting positions of two sets of signature detectors 1 and 2. As shown in the figure, a signature detector 1 (light emitter 1a, light receiver 1b) and a signature detector 2 (light emitter 2a, light receiver 2b) detect signatures above the conveyor belt 10, which is the signature conveyance path. They are attached at intervals of one page. In addition, in FIG. 2, the continuous printing paper 11 is separated by a cutting cylinder 12 and a folding cylinder 1.
3 and cut into pieces, folded by the folding cylinder 13 and the pick cylinder 14, and transferred to the conveyor belt 10. At this time, the cut and folded printed sheets (signatures) are transferred so as to maintain equal distances from each other. Thereafter, the signatures are moved along the path of the conveyor belt 10 (signature conveyance path) at equal distances (corresponding to one page of signatures in this case), and are sent out by the impeller 15. .
In the case of parallel output or two-stage output, the cutting cylinder 12, folding cylinder 13, pick cylinder 14, conveyor belt 10, and impeller 15 are provided in parallel or in two stages, and the above steps proceed in parallel, and the cutting cylinder 12. All rotating parts such as the conveyor belt 10 are synchronized. Hereinafter, the operation of the paper jam detection device for a web-fed rotary printing press according to this embodiment will be explained using time charts shown in FIGS. 3 and 4. First, after printing starts, when the signatures begin to pass on the path of the conveyor belt 10 with an interval of one signature page, the signature detectors 1 and 2 detect the respective positions of the signatures. While passing, an "H" level signal is output as shown in FIGS. 3A and 3B. In this case, if the signatures passing on the path of the conveyor belt 10 move while maintaining the interval of one page of signatures, one signature detector will detect the signature and the "H" level will be detected. When a signal is being output, the other signature detector is always not detecting a signature. Therefore, the output of the OR gate 3c of the paper jam determination circuit 3 becomes an "L" level signal indicating that there is no paper jam, as shown in FIG. 3E. However, if the movement timing of the signatures is shifted by Δt, the detection signals A and B of signature detector 1 and signature detector 2 will also be Δt.
The phase relationship shifts in accordance with the shift in t. Therefore, the AND gate 3a and the NOAH gate 3b
In response to the deviation of Δt, pulse signals with a pulse width Δt are output as a paper presence determination signal C and a paper absence determination signal D, respectively, as shown in FIGS. 3C and 3D. The paper presence determination signal C and the paper out determination signal D having a pulse width of Δt are input to the OR gate 3c, and are output from the OR gate 3c as a paper jam determination signal E having a pulse width Δt as shown in FIG. 3E. . However, the paper jam determination signal E with a pulse width Δt output from the OR gate 3c is attenuated in the delay circuit 3d because the delay time of the delay circuit 3d is set to a time τ larger than Δt. It is not output as the detection signal F. The signal in FIG. 3A is the signal generated from signature detector 1, and the signal in FIG. 3B is the signal generated from signature detector 2. In Figure 3, symbols A1 and B
Pulse 1 is the waveform when paper feeding is normal,
No paper jam signal is generated. After the preceding paper passes the signature detector 2 and generates a pulse of symbol B1,
If for some reason the succeeding paper is placed at a position after the time Δt from the position determined by the regular signature interval, the preceding paper will be placed on the signature detector 2.
T from the time the paper passes through until the subsequent paper reaches it
It takes +Δt time. When the paper reaches the signature detector 2, a pulse B3 is generated having a time T corresponding to one page of the signature. The speed of the signature conveyance path is constant, and if there is no abnormality in paper feeding thereafter, the paper fed after that point will be placed at the normal position, so the pulse B5 is generated at the normal timing. However, since the immediately preceding paper is behind the normal position by Δt, the period indicated by symbol B4 between pulses B3 and B5 becomes T-Δt. On the other hand, in the signature detector 1, the paper that generated pulse B1 generates pulse A2, the paper that generated pulse B3 generates pulse A4, and the paper that generated pulse B5 generates pulse A6. do. Therefore, the interval indicated by the symbol A3 between the pulse A2 and the pulse A4 is T+Δt, and the interval indicated by the symbol A5 between the pulse A4 and the pulse A5 is T−Δt. Therefore, the signals shown in FIG. 3D, E, and F are generated. However, at a certain time point _T1 , for example, if a paper jam occurs within the sensitive range of the signature detector 1,
The detection signal A output from the signature detector 1 becomes a DC signal of "H" level as shown in FIG. 4A.
After a delay of a travel time corresponding to one page of the signature, the output of the signature detector 2 also becomes an "H" level DC signal. Therefore, the AND gate 3a outputs the paper presence determination signal C at the "H" level until the paper jam is removed. The paper presence determination signal C (FIG. 4C) at this time is input as the paper jam determination signal E to the delay circuit 3d via the OR gate 3c, but since the signal is a continuous DC signal, the delay circuit 3d A paper jam detection signal F (FIG. 4F) which is obtained by delaying the paper jam detection signal E by τ time is outputted. The paper jam detection signal F output from the delay circuit 3d is input to a printing press control circuit (not shown), where it is temporarily stored and used as a stop signal for the printing press and a trigger signal for a paper jam alarm. In this way, according to this embodiment, paper jam detection is not performed at a certain inspection timing, but is constantly detected, so that a paper jam detection signal is immediately output when a paper jam occurs. The operation of the printing press can be stopped. In particular, the paper jam detection circuit is composed of a matching circuit that uses the detection signals output from two sets of signature detectors as inspection signals, so it only outputs a paper jam detection signal when a paper jam occurs. Not, but
Outputs a paper jam detection signal even when one side of the signature detector fails or when a disconnection or short circuit occurs in one of the input signal paths of the paper jam detection circuit and the input signal is fixed at the DC signal level. .
Therefore, failures in the paper jam detection device itself can be discovered before they occur, and paper jam detection can always be performed stably. Furthermore, since the detection signal output from the signature detector itself is a paper jam inspection signal, strict timing alignment is not required. Furthermore, even if there is a shift in the timing of signature movement that does not result in a paper jam even though paper jams are constantly being detected, or if short-term signals such as noise are superimposed, they will not be output as paper jam detection signals, so stable and accurate paper Blockage detection can be performed. In addition, only two sets of photoelectric signature detectors are required, and the wiring direction is the same, which saves material costs and makes wiring work easier. A detection device can be obtained. Further, although the case of two-row output or two-stage output is not described, the above-mentioned paper jam detection device can be provided corresponding to each folded line to detect paper jam. In particular, in the case of a two-row or two-stage pick-up machine, the movement of signatures is completely synchronized in each fold row, so two sets of signature detectors are installed in one fold row and It is possible to detect paper jams in double-fold rows by simply providing one set of signature detectors in each row. As explained above, according to the present invention, paper jam detection is not performed at a certain inspection timing, but is constantly detected, so that a paper jam detection signal is immediately output when a paper jam occurs. It is possible to stop the operation of the printing press by In particular, the paper jam detection circuit is composed of a circuit that uses the detection signals output from two sets of signature detectors as inspection signals, so it not only outputs a paper jam detection signal when a paper jam occurs. Outputs a paper jam detection signal even when one side of the signature detector fails, or when a disconnection or short circuit occurs in one of the input signal paths of the paper jam detection circuit and the input signal is fixed at the DC signal level. do. Therefore, failures in the paper jam detection device itself can be discovered before they occur, and paper jam detection can always be performed stably. Furthermore, since the detection signal output from the signature detector itself is a paper jam inspection signal, strict timing alignment is not required. Furthermore, even if there is a shift in the movement timing of signatures that does not result in a paper jam, or a short-time signal such as noise is superimposed even though paper jam detection is being performed constantly, it will not be output as a paper jam detection signal, so it is stable and accurate. paper jam detection. In addition, only two sets of photoelectric signature detectors are required, and the wiring direction is the same, which saves material costs and makes wiring work easier. This has extremely effective effects such as being able to obtain a detection device.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing an embodiment of a paper jam detection device for a rolled paper rotary printing press according to the present invention, FIG. 2 is a diagram showing the installation position of a signature detector, and FIGS.
The figure is a time chart for explaining the operation of the circuit shown in FIG. 1. 1, 2...signature detector, 3...paper jam detection circuit, 10...transport belt, 11...printing paper, 22
... Cutting cylinder, 13 ... Folding cylinder, 14 ... Mouth cylinder, 15
...impeller.

Claims (1)

[Scope of Claims] 1. First and second signatures arranged in series at an interval of one signature page on the signature conveyance path after the folding drum, and generating a signature passage signal when a signature passes. Detector 1, 2
By comparing the signals generated at the same timing from the first and second signature detectors, it is possible to detect when a signature should not be on the signature conveyance path at the set position of one signature detector. The paper presence determination signal generation circuit 3a outputs a paper presence determination signal in certain cases, and the signals generated at the same timing from the first and second signature detectors are compared to detect the fold at the set position of one signature detector. A paper-out determination signal generation circuit 3b outputs a paper-out determination signal when there is no signature when there should be a signature on the sheet conveyance path; A paper roll rotary press comprising: a paper jam signal generation circuit 3c that generates a signal; and a paper jam detection signal generation circuit 3d that outputs a paper jam detection signal when the paper jam signal continues for a predetermined period of time or more. Paper jam detection device for printing presses.