Method for adjusting the processing position of at least one processing device not clamping a product web to be processed
A method for adjusting the processing position of at least one processing device not clamping a product web to be processed within the context of longitudinal register control in a processing machine includes arranging the at least one processing device in a web section which is delimited by two clamping points. The method further includes applying an actuating variable for adjusting the processing position to the at least one processing device within the context of feedforward control, and calculating the actuating variable for adjusting the processing position on the basis of a register deviation expected from a control action of a tensile force control device for controlling the tensile force in the web section.
1. A method for adjusting the processing position of at least one processing device not clamping a product web to be processed within the context of longitudinal register control in a processing machine, comprising:
arranging the at least one processing device in a web section which is delimited by two clamping points;
calculating an expected register deviation that will result from a control action of a tensile force control device for controlling the tensile force in the web section;
calculating an actuating variable for adjusting the processing position on the basis of the expected register deviation resulting from a control action of a tensile force control device for controlling the tensile force in the web section; and
applying the actuating variable as a feedforward control to the at least one processing device.
2. The method according to claim 1 , wherein the actuating variable is calculated from a speed of the two clamping points and a stretch of the product web.
3. The method according to claim 1 , wherein the actuating variable is calculated from a speed of the at least one processing device.
4. The method according to claim 1 , wherein the actuating variable is calculated from positions of the at least one processing device and the two clamping points.
5. The method according to claim 1 , wherein the actuating variable is applied to the at least one processing device in order to shift the processing position by a distance which corresponds to the expected register deviation.
6. The method according to claim 1 , further comprising:
adjusting a processing length of the at least one processing device; and
applying an actuating variable for adjusting the processing length to the at least one processing device within the context of feedforward control,
wherein the actuating variable for adjusting the processing length is calculated from an expected speed change from a control action of a tensile force control device for controlling the tensile force in the web section.
7. The method according to claim 1 , wherein the actuating variable is transmitted to the at least one processing device via a bus connection.
8. The method according to claim 1 , wherein the actuating variable is generated as an output from an encoder emulation.
9. The method according to claim 1 , wherein feedforward control is carried out when a process variable changes.
10. The method according to claim 1 , wherein:
the processing machine is a digital printing press including at least one inkjet printing unit, and
the at least one inkjet printing unit is the processing device.
11. The method according to claim 1 , wherein the processing machine includes at least one laser processing device.
12. The method according to claim 1 , wherein a computing unit is equipped to carry out the method.