Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
  • B65H23/00—Registering, tensioning, smoothing or guiding webs
  • B65H23/04—Registering, tensioning, smoothing or guiding webs longitudinally
  • B65H23/18—Registering, tensioning, smoothing or guiding webs longitudinally by controlling or regulating the web-advancing mechanism, e.g. mechanism acting on the running web
  • B65H23/188—Registering, tensioning, smoothing or guiding webs longitudinally by controlling or regulating the web-advancing mechanism, e.g. mechanism acting on the running web in connection with running-web
  • B65H23/1882—Registering, tensioning, smoothing or guiding webs longitudinally by controlling or regulating the web-advancing mechanism, e.g. mechanism acting on the running web in connection with running-web and controlling longitudinal register of web
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41F—PRINTING MACHINES OR PRESSES
  • B41F13/00—Common details of rotary presses or machines
  • B41F13/02—Conveying or guiding webs through presses or machines
  • B41F13/025—Registering devices
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
  • B65H2513/00—Dynamic entities; Timing aspects
  • B65H2513/50—Timing
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S101/00—Printing
  • Y10S101/42—Means for tensioning webs

Definitions

• the invention relates to methods for controlling a web tension in a rotary printing press according to the preamble of claim 1 or 3.
• EP 09 51 993 A1 discloses a drive with a register for a rotary printing press, wherein a longitudinal expansion of the printing web is determined from web tension and operating values of the drives, and is compensated for by adjusting the circumferential register on the cylinders or the register rollers. A change in transverse stretch determined by a sensor for web width detection is fed back via a correction variable to the target value of the tension roller regulated to maintain web tension.
• the invention has for its object to provide methods for controlling a web tension in a rotary printing press.
• the object is achieved by the features of claim 1 or 3.
• the measurement if possible after the last printing unit, provides the greatest possible information about the operating state of the web before it enters the superstructure, especially the funnel inlet.
• the tension / elongation behavior of the web changes as it passes through the printing points and causes, for example, an increase in the elongation after the last printing unit.
• the appropriate web tension level of the webs should be adjusted to one another after switching on water and paint, if possible only by adjusting the feed mechanism.
• the paper web expands both in the longitudinal and in the transverse direction in relation to the transport direction. This is reflected, particularly in multi-color printing with free path lengths between adjacent printing points, as stretching of the web. As long as the effect at each printing point remains almost constant over time, this expansion can be compensated for at least in part, for example, by register adjustment on the cylinders, by changing the position of register rollers or other devices.
• the stretching behavior of the paper web is, however, subject to many influences such as Example of the tension / elongation characteristics of the respective paper and thus the prevailing tension, the current humidity, the sensitivity to moisture, the penetration behavior, the position of the roll during its manufacture in the reel, which is reflected, for example, in different winding hardness, or by a location-dependent fluctuation in the Modulus of elasticity.
• the elongation, both the longitudinal and the transverse expansion, is therefore not stationary because of the non-constant paper properties of the rolling paper web itself and because of changing and sometimes fluctuating operating parameters on the printing press.
• a fluctuating web tension, changing printing speed, fluctuations in the moistening or a change of the roll influence the elongation of the paper web, so that the elongation is not stationary over time.
• the method thus makes a constant readjustment of the cutting register of a web over all drives of the printing units or over register rollers at least partially unnecessary during ongoing production.
• Figure 1 is a schematic representation for guiding a web from the infeed unit via four printing units and a second pull roller to a funnel infeed roller.
• Fig. 2 is a schematic representation of the web tension levels in continuous printing.
• Fig. 1 shows schematically the course of a path B, z. B. a printing material web B or a paper web B, on its way through a printing press, in particular a web-fed rotary printing press.
• the web B runs in the transport direction T from the roll changer 01 via a feed unit 02 with a pull roller 03 through the four printing units 06 to 09, for example, to one second pull roller 11.
• the main pull rollers 03; 11 are in an advantageous embodiment, each with its own drive 13; 14 and a drive control 16; 17 equipped.
• tension S1, S2, S3 and S4 of the web B are measured between the pull roller 11 and the hopper inlet roller 12. This can take place, for example, via measuring rollers or the power consumption of the drive motors of the traction elements.
• the starting point for the adjustment of the tensions of a web B are, in particular if several webs B are combined at the funnel inlet at the funnel inlet by means of the funnel inlet roller 12, the absolute and relative tensions S4 of the individual webs B on the funnel inlet roller 12 to one another. Accordingly, the tension of the web B is set based on the desired level of tension S4 on the hopper inlet roller 12.
• the level of the total tension of the web B is preferably determined by adjustment on the feed mechanism 02.
• a change in the tension of the web B during the continuous printing also takes place advantageously by a change in the tension S2 at the feed mechanism 02.
• a basic setting of the tensions during the continuous printing, as shown schematically in FIG. 2, is done, for example, via the web tension and speed - Or position-controlled draw roller 03, the also controlled hopper feed roller 12 and / or dancer rollers, not shown.
• ⁇ 2 represents an expansion between first printing unit 06 and second printing unit 07
• ⁇ 3 an expansion between second printing unit 07 and third printing unit 08
• ⁇ 4 an expansion between printing unit 08 and printing unit 09
• the determination of the machine speed and / or the phase position of the machine can be done on the printing units 06; 07; 08; 09 done in different ways. For example, if each of the printing units 06; 07; 08; 09 is specifically driven, the performance data, the angular positions or other key figures of all or individual printing units 06; 07; 08; 09 can be used.
• a phase position ⁇ 1 of the first printing group 06 is measured via a first sensor 18.
• This phase angle ⁇ 1 can e.g. B. on a motor shaft of a drive 19 for a cylinder 21; in particular, a drive 19 of a forme cylinder 21 of the printing unit 06, for example by means of an encoder, can be tapped (shown in dashed lines in FIG. 1). If the forme cylinder 21 is coupled to a cooperating cylinder 22, in particular a transfer cylinder 22, the phase position ⁇ 1 on the transfer cylinder 22 can also be determined. As shown in FIG.
• the arrangement of a mark 23 as a reference point 23 on the forme cylinder 21 or on the transfer cylinder 22 can also be used together with a first sensor 18 to determine the phase position ⁇ 1 or a position ⁇ 1. This can be done, for example, using a scanner or a photocell.
• a mark 23 applied by the printing unit 06 itself, part of the printed image itself, perforation or other markings on the web B can also serve as a mark 23 for determining the first phase position ⁇ 1.
• a further sensor 24 is arranged in the transport direction T after the last printing unit, here the fourth printing unit 09.
• a second phase position ⁇ 2 or position ⁇ 2 of a mark 26 or at least part 26 of a print image of a printed web B is measured.
• the mark 26 can also be perforated the path B or an equivalent marking on the path B.
• the phase position ⁇ 2 of the mark 26 is understood here to mean the chronological sequence of the passage of the mark 26 at the detector. If the phase position ⁇ l is determined via a mark 23 arranged on the path B (as mentioned alternatively), the mark 23 can be used to determine the phase position ⁇ 2, which in this case are identical.
• the phase position ⁇ 1 of the printing unit 06 is first determined by measuring the passage of the mark 23. After passing through the printing units 06 to 09, the second phase position ⁇ 2 of the mark 26 printed on the web B or the part of the printed image 26 is determined after the last printing unit 09. Taking into account a fixed position of the measuring points relative to each other, a fixed phase shift ⁇ would now be ascertainable with a constant expansion ⁇ of the web B over all sections. This is where the method for controlling a web tension in a rotary printing press comes into play, since the stretch ⁇ of web B is not constant over time during production for the reasons mentioned above.
• the setpoint ⁇ setpoint can differ from production to production, since it depends on the register status of the printing units 06 to 09. However, it should only be set in stationary and trouble-free operation.
• the setting of the register status and the voltages S1 to S4 are, as already shown above, in their basic setting as a rule. even before the start of production, tailored to the paper properties, the web run and others. Parameters.
• the phase positions ⁇ 1 and 2 and thus the phase shift ⁇ are determined and with the Setpoint ⁇ setpoint compared. If the deviation ⁇ in the difference ⁇ from the nominal value ⁇ -nominal occurs during the ongoing printing of the current production due to one of the above reasons, this is an indication of a change ⁇ in the elongation ⁇ of the web B.
• an increase in the elongation ⁇ by ⁇ causes, for example, a deviation ⁇ in the phase shift ⁇ from the setpoint ⁇ setpoint.
• This deviation ⁇ , and thus also the change ⁇ in the elongation ⁇ is now compensated with the feed unit 02 upstream of the first printing unit 06 by changing the input extension ⁇ 1 until the setpoint ⁇ -target for the phase shift ⁇ is restored.
• the control can also allow certain tolerances in the deviation of the phase shift ⁇ from the target value ⁇ -target before the countermeasure of a change in the input stretch ⁇ 1 is taken.
• the deviation ⁇ from the target value ⁇ -target can, for example, be superimposed as a disturbance variable ⁇ on a target value transmitter of the drive control 16.
• the drive control 16 of the pull roller 03 can be regulated, for example, with respect to the torque, with the voltage S2 being fed back.
• a path of the web B via a corresponding measuring roller 27 for the measurement of the tension S2 of the web B is dashed in FIG. 1 shown.
• the disturbance variable ⁇ > corresponding to the deviation ⁇ from the reference value ⁇ -target is superimposed on the setpoint generator of the drive control 16, for example as a correction variable ⁇ S2.
• Such a correction variable ⁇ S2 can, for example, be taken from a stored curve for the dependence on ⁇ S2 over ⁇ or can also be carried out iteratively by raising or lowering the voltage S2 until the phase shift ⁇ again corresponds to the desired value ⁇ -target.
• a DROOP behavior is a load-dependent change in the nominal value of a circumferential or angular speed or rotational speed, which both a change in the tension of the web B, z. B. S4, as well as a change in angular velocity.
• a correction variable ⁇ S2 is superimposed on the setpoint S2 target for the tension S2, which together with the actual value of the tension S2 using the DROOP function results in a corresponding lag of the pull roller 03, and thereby a different tension S2 and the resulting input extension ⁇ 1 results, which ultimately also results in a change in the elongation ⁇ .
• the setpoint ⁇ -target for the drive control 16 is a disturbance variable ⁇ determined from the phase shift ⁇ and the setpoint ⁇ -target. for example, as a correction quantity ⁇ S2 of the desired voltage S2.
• the phase position ⁇ 1 can also be determined on one of the following printing units 07 to 09 instead of the first printing unit 06 in the transport direction T.
• the phase shift ⁇ is then to be determined between the relevant printing group 06 to 09 and the passage of the mark 23 on the sensor 24.
• the deviation ⁇ of the phase shift ⁇ from the set value ⁇ set is again used as the disturbance variable ⁇ for the drive the pull roller 03 processed.
• the correction variable ⁇ S2 as the voltage change ⁇ S2 can also be changed in a different way than on the pull roller 03.
• the change in the voltage S2 due to the disturbance variable ⁇ also includes changes in the action of force by a dancer roller (not shown) or other adjusting devices for the voltage S2 arranged in front of the first printing unit 06.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Controlling Rewinding, Feeding, Winding, Or Abnormalities Of Webs (AREA)
• Inking, Control Or Cleaning Of Printing Machines (AREA)
• Control Of Electric Motors In General (AREA)

Applications Claiming Priority (3)

Publications (2)

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ID=7649891

Family Applications (1)

Country Status (8)

Families Citing this family (16)

Family Cites Families (15)

• 2000
  • 2000-07-22 DE DE10035788A patent/DE10035788C1/de not_active Expired - Fee Related
• 2001
  • 2001-07-19 WO PCT/DE2001/002718 patent/WO2002007975A1/fr active IP Right Grant
  • 2001-07-19 US US10/296,247 patent/US7040231B2/en not_active Expired - Fee Related
  • 2001-07-19 JP JP2002513694A patent/JP3876225B2/ja not_active Expired - Fee Related
  • 2001-07-19 AU AU2001285679A patent/AU2001285679A1/en not_active Abandoned
  • 2001-07-19 AT AT01964839T patent/ATE376930T1/de not_active IP Right Cessation
  • 2001-07-19 ES ES01964839T patent/ES2294022T3/es not_active Expired - Lifetime
  • 2001-07-19 EP EP01964839A patent/EP1303404B1/fr not_active Expired - Lifetime
  • 2001-07-19 DE DE50113198T patent/DE50113198D1/de not_active Expired - Fee Related

Non-Patent Citations (1)

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