DE102017208512B3 - Method for compensating rotational vibrations in the operation of a sheet-processing machine with a vibration compensation model - Google Patents

Abstract

The invention relates to a method for compensating rotational vibrations during operation of a sheet-processing machine with a vibration compensation model, wherein the machine (1) into individual modules (DW1, DW2, DW3, DW4, DW5), units and / or assemblies is divided, wherein for the individual modules (DW1, DW2, DW3, DW4, DW5), units and / or assemblies necessary torque profiles are determined, depending on the configuration of the machine (1) and depending on the setting on the machine (1) a total excitation vector is determined. The invention has for its object to provide an alternative method for the compensation of rotational vibrations. In particular, it may be object of the invention to provide a method which allows a simple and efficient way to compensate for the design-related excitations of a sheet-processing machine, in particular a sheet-fed press, by corresponding counter-moments. According to the invention the object is achieved in that the total excitation vector based on at least one compensation point of the machine (1) converted and then fed inversely as compensation of excitations.

Description

The invention relates to a method for compensation of rotational vibrations in the operation of a sheet-processing machine with a vibration compensation model.

For example, in printing press construction, various drive configurations and methods are known in order to compensate for or avoid vibrations of the machine. In this case, vibrations are often detected metrologically and then determined from the measurement results a counter-moment for vibration compensation. This can be done once during commissioning or online as a continuous process.

However, procedures which require a special measuring procedure during commissioning require additional time and qualified persons during commissioning. Continuously working "learning" processes have the disadvantage that the behavior of the machine depends on the "previous history" (list of previous jobs, speed, running time, etc.). Also, in adaptive processes, the stability of the process must be guaranteed under all circumstances. Last but not least, permanently active procedures require accurate measuring equipment and the corresponding computing power that must be installed on each machine.

From the DE 10 2004 031 508 A1 a method for the correction of registration differences is known in which a torque flow model is used to determine the registering tolerances and to actuate corresponding circumferential register setting devices.

From the DE 10 2006 007 181 A1 a control of a printing press by means of a torsion model is known in which a torsional state in the printing machine is determined and compensated for by register adjustment.

From the EP 1 040 917 B1 For example, a method and a device for compensating the torsional vibrations of a printing machine are known, in which at least one of the characteristic shapes of the printing press is determined. At a location of the drive train, a counter-torque for the compensation of the moments that stimulate the oscillation in the eigenmode is applied in such a way that the oscillation is maximally reduced by the application of the at least one counter-moment.

From the EP 1 202 147 B1 For example, there is known a method of mechanical vibration compensation in machines wherein at least one pair of amplitudes and phases of the compensating substantially harmonic moment are calculated in a closed adaptive control loop, the process parameters required for the calculation being different based on at least two measurements of the discrete frequency fraction Times are updated with different compensation parameters during the control.

From the EP 1 674 258 B1 a method for the compensation of Rotationsschwingungsbedingten Passerabweichungen is known, wherein harmonic compensation moments are determined after a single detection of rotational vibrations and stored in conjunction with resonance speed ranges and these compensation moments are superimposed on the drive torque of the main drive motor speed-dependent.

The invention has for its object to provide an alternative method for the compensation of rotational vibrations. In particular, it may be object of the invention to provide a method which allows a simple and efficient way to compensate for the design-related excitations of a sheet-processing machine, in particular a sheet-fed press, by corresponding counter-moments.

According to the invention the object is achieved by a method having the features of the independent method claim. Advantageous embodiments will become apparent from the dependent claims, the description and the drawings.

Advantageously, nothing has to be measured or set extra on an individual machine. Instead, the counter-torque required for vibration damping can be determined, for example, by a controller in a simple manner from the machine configuration and the excitation vectors of the individual modules, units and / or assemblies. In particular, the counter moment is calculated. The individual modules can preferably be identical works of the machine. Particularly preferably, the modules can be printing units and / or coating units of a sheet-fed printing press.

The invention is based in particular on the idea that the predominant portion of the vibration excitation on a sheet-processing machine, for example a sheet-fed printing press, is constructive, ie. H. resulting from the moments of non-uniform translating gear. Therefore, the machine is preferably divided into individual modules, units or assemblies for the necessary drive torque curves are known or calculated. These moments act on the oscillatory overall system as excitations, which can be represented as a vector or space vector.

For example, depending on the configuration of a machine, such as the number of plants, in particular printing units and / or coating units on sheetfed press, and depending on the setting or settings on the machine, in particular a setting of a current sheet size, for example, operated in a mode perfecting Sheet-fed printing machine, or a rotation after a change of rotation, from the excitation vectors of the individual modules, aggregates and / or assemblies a weighted total excitation vector can be calculated or calculated. The overall exciter vector is in particular a function of the current machine speed.

This weighted total excitation vector can then be converted to a compensation point (eg main drive, brake drive, other drives or any combination) and a certain output speed and inversely fed as compensation for the excitations. By feeding the counter-moments at the compensation point of the machine, these counter-moments preferably act via a continuous drive wheel train on all modules, units and / or assemblies, which formed the basis for calculating the counter-moments. Advantageously, no counter-moments are stored in the vibration compensation model, but only a simple vector calculation after z. B. made a setting change.

In the following, the invention will be explained by way of example. The accompanying drawings show schematically:

1 Sheet-fed printing machine with, for example, five printing units;

2 : Self-oscillating form of the sheet-fed printing press with five printing units.

The 1 shows a sheet-processing machine, such as a sheet-fed press 1 , in particular a sheet-fed rotary printing machine preferably in aggregate and series construction. The machine contains any number of sheet-processing works, which can be performed, for example, as an investment, printing, - paint, drying and / or finishing plant or inline processing plant. In the aggregate and series construction, the successively arranged works of the machine are preferably carried out largely identical, for example, identical substructure modules can be used. Furthermore, the machine may include a feed sheet feeder and a delivery tray for outputting the processed sheets. Between two plants of the machine can also be arranged a turning device, with which the sheets are turned in an operating mode perfecting. The machine contains, for example, several plants, here for example five printing units DW1, DW2, DW3, DW4, DW5, whereby a last work can be designed as a paint, dry, finishing or inline processing plant. Furthermore, the machine could also have inline processing facilities and / or one or more inline processing plants, which can be designed, for example, as a film finishing plant, calendering plant, stamping station, numbering station, screen printing unit, perforating station and / or embossing station.

The printing units DW1, DW2, DW3, DW4, DW5 preferably each contain a transfer cylinder or blanket cylinder and a forme cylinder or plate cylinder. A blanket cylinder of a printing unit DW1, DW2, DW3, DW4, DW5 cooperates with a respective sheet guiding cylinder, in particular a printing cylinder. Between the sheet guiding cylinders, in particular printing cylinders, sheet guiding cylinders, in particular transfer drums or transfer cylinders, are also preferably provided. The sheet guiding cylinders, in particular printing cylinders or transfer drums or transfer cylinders, are here several times larger, preferably double in size, and the blanket cylinders and the plate cylinders are of simple size. Single-sized cylinders can hold approximately one and a double-sized cylinders at the same time in approximately two sheets of maximum size at the same time. In an alternative embodiment, the one or more sheet guiding cylinders, in particular printing cylinders, could also be simple, triple-sized or larger.

The here particularly double-sized sheet guiding cylinder, in particular printing cylinder or transfer drums or transfer cylinders, preferably each have two gripper systems for transporting the sheet. This particular diametrically opposed gripper systems hold the sheet to be processed, for example, a substrate, on the respective sheet guiding cylinder. The sheets are transferred between the sheet guiding cylinders in the gripper closure. The last work of the machine is preferably followed by a delivery with a delivery chain, which by means of gripper carriage, the sheets from the last sheet guiding cylinder, in particular printing cylinder, takes over and transported to a delivery stack.

The printing cylinders in the machine preferably have full-surface lateral surfaces and are here with rubber cylinders and this further with the plate cylinders in the printing units DW1, DW2, DW3, DW4, DW5 in operative connection. In the printing units DW1, DW2, DW3, DW4, DW5 known color or inking and dampening are arranged, the corresponding ink on a stretched on the respective plate cylinder pressure plate muster. A plate cylinder is colored by at least one but preferably several rollers of the associated inking or inking and dampening unit during its rotation. When unrolling the plate cylinder on the blanket cylinder, the printing ink is transferred to the blanket covered with a rubber blanket. Between a blanket cylinder and a printing cylinder, a printing zone is formed, through which the sheet to be printed is conveyed by the printing cylinder by means of the gripper systems. In the printing zone or in the printing nip, the printing ink is transferred from the blanket cylinder to the sheet in a motif-compatible manner.

A plate cylinder and a blanket cylinder of a respective printing unit DW1, DW2, DW3, DW4, DW5 preferably each have a cylinder pin on both sides, via which the cylinders are rotatably mounted in the frame of the respective printing unit DW1, DW2, DW3, DW4, DW5. Both plate cylinder and blanket cylinders preferably each have on both sides arranged not shown bearer rings. The plate cylinder bearer rings are in contact with the blanket bearer rings during the printing process and roll against each other under pressure. The bearer rings are preferably dimensioned such that no significant torque transfer between the cylinders takes place in the printing operation, that is, no predetermined moment is transmitted via the bearer rings.

In particular, the machine has a drive wheel train, which particularly preferably drives the impression cylinders of the printing couples DW1, DW2, DW3, DW4, DW5 as a continuous drive wheel train. Preferably, the sheet guiding cylinders designed as transfer drums or transfer cylinders are also driven by the drive wheel train. For this purpose, the impression cylinders and the transfer drums or transfer cylinders each have intermeshing toothed wheels which form the drive wheel train. The drive wheel train is driven by at least one main drive motor, which drives centrally or preferably in the region of the first work of the machine. The input drive of the main drive motor preferably takes place in the first printing unit DW1 directly following the installation in the direction of sheet travel, in particular on the gear assigned to the shaft of the first impression cylinder. Through the continuous drive wheel train, the cylinders or drums are driven together about their respective axis of rotation. The rubber cylinders of the printing units DW1, DW2, DW3, DW4, DW5 are preferably also driven by the drive wheel train. Further rotational bodies or rollers of the machine or of the printing units DW1, DW2, DW3, DW4, DW5 can also be driven at least temporarily by the drive wheel train, wherein these can also be designed to be coupled to the drive wheel train.

For example, one or each plate cylinder of a printing unit DW1, DW2, DW3, DW4, DW5 is assigned a single drive, in particular a plate cylinder direct drive. Direct drives are in particular individual drives whose rotors are mounted in alignment and concentric preferably directly to the associated cylinders. During printing, the plate cylinder in question is then tracked electronically synchronized with the rubber cylinder, which is preferably driven by the main drive motor via the drive wheel train. For this, the plate cylinder and / or blanket cylinder can be assigned a rotary encoder, which can be connected to a control unit of the printing unit DW1, DW2, DW3, DW4, DW5 and / or the machine control. Alternatively, the drive of the plate cylinder or can also be done via the drive wheel train from the main drive motor. Other individual or direct drives can be arranged in one or more plants of the machine.

The machine, especially the sheetfed press 1 , is excited during operation, especially in printing operation, by workers and drive torques for non-uniform transmission gear to vibrate. In particular, all essential excitations in the machine are clock-bound. These excitations are therefore composed of different harmonic components, each of which is an integer multiple of the machine clock (referred to as harmonics or orders). The excitations of a module, for example a printing unit DW1, DW2, DW3, DW4, DW5, aggregates and / or an assembly can therefore be described for each order by a respective vector, which is defined by amplitude and phase. The amplitude is significantly dependent on the speed of the machine. As an approximation, the amplitude of an excitation vector of an order can be decomposed into a constant moment (from spring forces), a linear speed-dependent torque (from friction) and a quadratic speed-dependent torque (from mass forces). For simplicity, the friction can be neglected so that the excitation vector of each order can be represented as the sum of a constant and a quadratic speed dependent term. All relevant orders together, then give a total matrix of the exciters of each module, unit or assembly.

These constructively given parameters are preferably calculated in advance, for example from CAD data, for each module, unit and / or module (printing unit DW1, DW2, DW3, DW4, DW5, system, etc.) and preferably stored in the control room. In the vicinity of a natural frequency of the machine dominates in each case a certain oscillating shape. For this area with a dominant oscillating shape, it is approximately true that a "total exciter vector" can be calculated from the module-, aggregate- and / or module-related excitation vectors by generating the excitations of a certain order from all modules, aggregates and / or assemblies. "Vibration weighted" means that for a given excitation, the relative local oscillation amplitude is important (see natural oscillation of the sheet-fed press according to US Pat 2 ).

The 2 shows a natural vibration shape of the machine, in particular sheet-fed press 1 , with the five printing units DW1, DW2, DW3, DW4, DW5. The relative local oscillation amplitude results for each module, unit and / or assembly from the dominant machine oscillation form. The oscillation amplitude shown is zero in the vibration node (in the third printing unit DW3 in FIG 2 ) and maximum at the end of the machine (first printing unit DW1 and fifth printing unit DW5 in 2 ).

The natural frequencies of the machine, in particular sheet-fed press 1 , can be calculated approximately from the spring-mass ratios or (as the exciter parameters of the modules, units and / or assemblies) are stored in the control room or the controller. With the aid of the total exciter vector, it is then possible to calculate a vectorial compensation moment for the point (s) of compensation (eg main drive, additional drive at the end of the machine or a combination) which is impressed or fed into the machine for vibration compensation.

Since the vectorial calculation is preferably always carried out only when essential settings change (for example, when a change of rotation and / or a format adjustment etc. takes place), it can also be executed on a slow control. The result of these calculations (the compensation vector) is then preferably stored in the control or the control center. Once the compensation vector has been determined, the particular angle-dependent compensating torque can be calculated simply and quickly, so that only a moderate additional requirement for the computing power of the controller results.

The mode of action: The method for compensation of excitation in machines, especially in, for example, long sheet-fed presses 1 , makes it possible to easily determine or calculate a compensation vector from excitation data already known at the time of construction in order to reduce rotational vibrations of the machine and thus to improve the print quality. No elaborate measurements are required for a particular machine - neither at start-up time nor during ongoing printing operation.

The decomposition into excitation vectors of discrete individual modules, assemblies or assemblies makes it possible to easily calculate the compensation vector for any configurations of machines as well as for certain relevant settings. This calculation takes place z. For example, when loading a new job or after certain adjustments (eg, adjustment of the turn format). Other settings (for example, adding and removing printing units DW1, DW2, DW3, DW4, DW5, etc.) can also be taken into account. The additional requirements for the control are moderate and no additional measuring elements or complex signal processing are required.

By means of the described method, rotational or torsional vibrations within machines, in particular sheet-fed printing machines 1 , be substantially downsized. As a result, reduce the cutting moments within the drive wheel train.

LIST OF REFERENCE NUMBERS

1

 Sheetfed

DW1

 first printing unit

DW2

 second printing unit

DW3

 third printing unit

DW4

 fourth printing unit

DW5

 fifth printing unit

Claims (12)

Method for compensating rotational vibrations during operation of a sheet-processing machine ( 1 ) with a vibration compensation model, wherein the machine ( 1 ) into individual modules (DW1, DW2, DW3, DW4, DW5), aggregates and / or assemblies is divided, whereby for the individual modules (DW1, DW2, DW3, DW4, DW5), units and / or assemblies necessary torque profiles are determined , depending on the configuration of the machine ( 1 ) and depending on the setting on the machine ( 1 ) a total excitation vector is determined, this total excitation vector being applied to at least one compensation point of the machine ( 1 ) converted and then fed inversely as compensation of excitations. A method according to claim 1, characterized in that a weighted and / or waveform-weighted total excitation vector. A method according to claim 1 or 2, characterized in that the necessary drive torque curves are known or calculated. Method according to claim 1, 2 or 3, characterized in that the configuration of the machine ( 1 ) a number of printing units (DW1, DW2, DW3, DW4, DW5) and / or coating units on a sheet-fed printing machine ( 1 ). Method according to claim 1, 2, 3 or 4, characterized in that the adjustment on the machine ( 1 ) the setting of a current sheet format, in particular on a sheet-fed printing press which can be operated in a perfecting mode ( 1 ). The method of claim 1, 2, 3, 4 or 5, characterized in that the total excitation vector of excitation vectors of the individual modules (DW1, DW2, DW3, DW4, DW5), aggregates and / or assemblies is calculated. A method according to claim 1, 2 3, 4, 5 or 6, characterized in that the at least one compensation point a main drive, a brake drive and / or other drive of the machine ( 1 ) assigned. Method according to claim 1, 2, 3, 4, 5, 6 or 7, characterized in that the machine ( 1 ) into individual similar modules (DW1, DW2, DW3, DW4, DW5), aggregates and / or assemblies is divided. The method of claim 1, 2 3, 4, 5, 6, 7 or 8, characterized in that the total excitation vector, taking into account modules incorporated and outsourced (DW1, DW2, DW3, DW4, DW5), aggregates and / or Assemblies is determined. Method according to claim 1, 2 3, 4, 5, 6, 7, 8 or 9, characterized in that the determination of the total excitation vector takes place only once and until a change in a setting on the machine ( 1 ) remains valid. A method according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10, characterized in that the total excitation vector is at least one compensation point and the speed of the machine ( 1 ) is converted. The method of claim 1, 2 3, 4, 5, 6, 7, 8, 9, 10 or 11, characterized in that the inverse feeding of the total excitation vector depending on the machine angle and / or the machine speed during the machine run by means of the vibration compensation model he follows.

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