Good register coordination of printing cylinders in a web-fed rotary printing press

• US 6,532,872 B2
• Filed: 05/22/2001
• Issued: 03/18/2003
• Est. Priority Date: 06/02/1997
• Status: Expired due to Fees

• Current Assignee: Maschinenfabrik Wifag
• Original Assignee: Maschinenfabrik Wifag
• Inventors: Helfenstein, Andreas, Siegl, Walter
• Primary Examiner(s): Eickholt, Eugene H.
• Application Number:
  US09/863,780
• Publication Number:
  US 20020023560A1
• Time in Patent Office: 665 Days
• Field of Search: 101/483, 101/484, 101/485, 101/151, 101/248, 101/211, 101/232, 101/181, 101/216, 700/28, 700/29, 700/33, 700/37, 700/38, 700/63, 700/45
• US Class Current: 101/483
• CPC Class Codes: B41F 13/0045 Electric driving devices
• CPC Class Codes: B41F 13/12 Registering devices
• CPC Class Codes: B41F 33/00 Indicating, counting, warning, control or safety devices arrangements of counting devices in platen presses B41F1/00 , B41F1/58; arrangements of counting devices in cylinder presses B41F3/84; ink supply or metering devices B41F31/02
• CPC Class Codes: B41P 2213/734 each printing unit being driven by its own electric motor, i.e. electric shaft
• CPC Class Codes: B65H 2557/2644 characterised by PID control

Abstract

The present invention pertains to the coordination in good register of cylinders of a web-fed rotary printing press which print on a web, wherein a first cylinder printing on one side of the web is driven by a first motor and a second cylinder printing on the same side of the web is driven by a second motor and the angular position of the second cylinder is coordinated with the first cylinder in good register by a controller. At least one disturbance variable (v) is sent to a command variable (u_2.Soll) for the motor controller of at least the second cylinder to compensate a register deviation (Y₁₂) of the second cylinder from the first cylinder, which register deviation is typical of the said disturbance variable (v).

Claims

1. A process for register coordinating cylinders of a web-fed rotary printing press, the process comprising the steps of:

providing a web;

printing on one side of said web with a first cylinder;

driving said first cylinder with a first motor;

printing on said one side of said web with a second cylinder;

driving said second cylinder with a second motor;

controlling said motors for maintaining preset angular positions of said first and second cylinders, said controlling using motor controllers associated with said motors,

mixing a velocity (v₂) of one of said cylinders as a disturbance variable with a command variable (u_2.Soll) for said motor controller of said second cylinder to compensate a register deviation (Y₁₂) of said second cylinder from said first cylinder, said register deviation being typical of said disturbance variable (v), said register deviation (Y₁₂) is preset as a function of said disturbance variable (v₂) in a form of at least one characteristic in order to form a correction variable (du_2.S), said correction variable is sent to said motor controller of said second cylinder.

2. A process in accordance with claim 1, wherein:

velocity-dependent register deviations are determined and preset for alternative paths of conveyance of the web.

3. A process in accordance with claim 1, wherein:

one of said controllers is a PID controller, during a change in a production condition, one of controller parameters k_P, k_D, k_I, and k_f of said PID controller is changed to coordinate said second cylinder in good register, and a setting of this said controller is adapted to said production condition as a result.

4. A process in accordance with claim 3, wherein:

one of parameter basic values k_{P Basis}, k_{D Basis}, k_{I Basis}, and k_{f Basis} of the PID controller is specific to a production and is used to form said one controller parameter (k_P, k_D, k_I, k_f).

5. A process in accordance with claim 3, wherein:

said one controller parameter (k_P, k_D, k_I, k_f) is affected by a change in a web length as a consequence of a transformation of a print position.

6. A process in accordance with claim 3, wherein:

said one controller parameter (k_P, k_D, k_I, k_f) is changed in adaptation to a circumferential velocity of one of said cylinders.

7. A process in accordance with claim 1, wherein:

a third cylinder printing on said one side of the web is uncoupled from a correction of a register deviation (Y₁₂) of said second cylinder, said correction being performed for said second cylinder by sending a variable (du_2.R) for said second cylinder to an uncoupling member EG₂₃₄ and by mixing an output signal (E₂₃₄) of said uncoupling member with a setting variable (du_3,R) for correcting register deviations (Y₁₃) of said third cylinder, said variable bringing about said correction of said register deviation (Y₁₂) of said second cylinder.

8. A device for coordinating registration of cylinders of a web-fed rotary printing press which print on a web, the device comprising:

a first cylinder printing on one side of the web;

a first motor driving said first cylinder;

a second cylinder printing on said one side of the web;

a second motor driving said second cylinder;

motor controllers associated with each of said motors for maintaining preset angular positions of said first and second cylinders,

a control member forming a correction variable (du_2.S) from a speed of said cylinders, said speed being used as a disturbance variable (v) for compensating a register deviation (Y₁₂) of said second cylinder from said first cylinder, said register deviation (Y₁₂) being typical of said disturbance variable, said correction variable being sent to said motor controller of said second cylinder, said control member has a memory including a curve of the register deviation (Y₁₂) of said second cylinder from said first cylinder (11), said curve being a function of said disturbance variable (v).

9. A device in accordance with claim 8, wherein:

said control member includes first and second inputs, said disturbance variable (v) is sent to said control member via said first input, one of a characteristic (Y₁₂(v)) which is valid for a current print production, and a selection signal for selecting this characteristic from among other characteristics stored in said memory of said control member is sent to said control member via said second input.

10. A device in accordance with claim 8, further comprising:

a PID controller for coordinating in good register said second cylinder with said first cylinder, said controller including one of controller parameters k_P, k_D, k_I, and k_f which is changed during operation of the press.

11. A device in accordance with claim 10, further comprising:

a signal processor and a memory in said controller;

a higher control means for transmitting one of parameter basic values k_{P Basis}, k _{D Basis}, k_{I Basis}, and k_{f Basis} to said signal processor and said memory in said controller, said parameter basic values (k_{P Basis}, k_{D Basis}, k_{I Basis}, k_{f Basis}) forming said controller parameters (k_P, k_D, k_I, k_f).

12. A device in accordance with claim 10, wherein:

a circumferential velocity of one of said cylinders is fed into said controller.

13. A device in accordance with claim 12, wherein:

said controller multiplies said circumferential velocity by said parameter basic value (k_{P Basis}, k_{D Basis}, k_{I Basis}, k_{f Basis}) to form said one controller parameter (k_P, k_D, k_I, k_f).

14. A device in accordance with claim 10, wherein:

said control member is part of said controller.

15. A device in accordance with claim 11, wherein:

said control member is independent of said higher control means.

16. A device in accordance with claim 11, wherein:

said control member is part of said higher control means.

17. A process for register coordinating cylinders of a web-fed rotary printing press, the process comprising the steps of:

providing a web;

printing on one side of said web with a first cylinder;

driving said first cylinder with a first motor;

printing on said one side of said web with a second cylinder;

driving said second cylinder with a second motor;

providing a characteristic for the printing press relating a typical register deviation of said second cylinder from said first cylinder as a function of velocity of one of said cylinders;

measuring a velocity of one of said cylinders;

determining said typical register deviation from said characteristic based on said measured velocity;

adjusting said driving of one of said first and second cylinders based on said typical register deviation determined from said characteristic.

18. A process in accordance with claim 17, further comprising:

providing a plurality of said characteristics for different conditions of the printing press;

determining said different conditions;

choosing one of said plurality of characteristics based on said determined conditions;

using said one of said plurality of characteristics in said step of determining said typical register deviation.

19. A process in accordance with claim 17, further comprising:

measuring an actual register deviation;

adjusting said driving of said one of said first and second cylinders based on said typical register deviation and said actual register deviation.