Sheet-fed printing press with a sensor system and methods for calibrating and for aligning the sensor system

Patent metadata

Field	Value
Publication number	US-10131137-B2
Application number	US-201715446225-A
Country	US
Kind code	B2
Filing date	Mar 1, 2017
Priority date	Mar 3, 2016
Publication date	Nov 20, 2018
Grant date	Nov 20, 2018

Abstract

A sheet-fed printing press includes a printing cylinder and a high-precision sensor system for monitoring a sheet run in the area of the printing cylinder. At least one gage, which is mounted on the printing cylinder, can be detected by the sensor system. It is particularly advantageous if the sensor system is configured to be self-calibrating. A method for calibrating a sensor system and a method for aligning a sensor system are also provided.

First claim

The invention claimed is:

1. A sheet-fed printing press, comprising:
a sheet run area for guiding a sheet run in a sheet transport direction;
a printing cylinder having two end faces;
at least one gage being mounted on said printing cylinder; and
a sensor system for monitoring the sheet run in a vicinity of said printing cylinder and for detecting said at least one gage, said sensor system being disposed in said sheet run area, said sensor system including a light curtain having a multiplicity of laser beams, and said sensor system including a transmitter and a receiver;
said transmitter being disposed at one of said end faces and said receiver being disposed at another of said end faces of said printing cylinder defining a viewing direction of said sensor system at right angles to said sheet transport direction.

2. The sheet-fed printing press according to claim 1 , wherein said sensor system is self-calibrating.

3. The sheet-fed printing press according to claim 1 , wherein said at least one gage images different sheet heights over an angle of rotation.

4. The sheet-fed printing press according to claim 1 , wherein said printing cylinder includes a channel, and said at least one gage is mounted in said channel or next to said channel.

5. The sheet-fed printing press according to claim 1 , wherein said printing cylinder has two sides, said at least one gage includes at least two gages, at least one of said gages is disposed on one side and at least one other of said gages is disposed on the other side of said printing cylinder.

6. The sheet-fed printing press according to claim 5 , wherein said at least two gages are disposed with a mutual angular offset on said printing cylinder.

7. A method for calibration of a sensor system for monitoring a sheet run in a vicinity of a printing cylinder of a sheet-fed printing press, the method comprising the following steps:
attaching at least one gage to the printing cylinder;
using the sensor system to detect the at least one gage during rotation of the printing cylinder and to provide a measurement result;
storing a desired value in a sensor controller and assigning a certain desired value as a measured value to a specific angle of rotation in the sensor controller;
comparing the measurement result with the stored desired value; and
if necessary, performing a correction of the sensor system for the calibration by storing the measured value as a threshold value for monitoring the sheet run in the sensor controller upon a deviation of the measured value from the desired value.

8. The method for calibrating according to claim 7 , which further comprises taking manufacturing tolerances of the at least one gage into account in the calibrating and using the manufacturing tolerances for codetermining the desired value.

9. A method for aligning a sensor system for monitoring a sheet run of sheets of different thickness in a vicinity of a printing cylinder of a sheet-fed printing press, the method comprising the following steps:
providing a printing cylinder having two sides;
attaching at least one gage supplying measured values on one of the sides and attaching at least one other gage supplying measured values on another of the sides of the printing cylinder;
using the sensor system to detect the at least two gages;
providing the sensor system with a transmitter, a receiver and a light curtain with a multiplicity of laser beams;
placing the transmitter on one side and placing the receiver on the other side of the printing cylinder;
adjusting the sensor system independently on the one side of the printing cylinder having the transmitter and on the other side of the printing cylinder having the receiver for a parallel position of the sensor system;
storing a threshold value in a machine controller; and
comparing the measured values of the gages and making a correction of the position of the transmitter and the receiver or displaying a warning, upon exceeding the threshold value stored in the machine controller.

10. The method for aligning according to claim 9 , which further comprises taking manufacturing tolerances of the gages into account when aligning for aligning the sensor system parallel to the printing cylinder.

Assignees

• Heidelberger Druckmasch Ag

Inventors

• Henn Andreas
• Schmidt Thomas
• Kabus Wolfgang
• Knauf Stefan
• Ritz Juergen
• Lorenz Olaf
• Bull Christian
• Muench Stefan
• Goebel Thomas

Classifications

• B41F27/005 Primary

  Attaching and registering printing formes to supports · CPC title

• B41J13/223

  on rotatable drums · CPC title

• B41J11/0035 Primary

  Handling copy materials differing in thickness (B41J11/20 takes precedence) · CPC title

• B41J11/0095 Primary

  Detecting means for copy material, e.g. for detecting or sensing presence of copy material or its leading or trailing end · CPC title

• B41F33/0063

  Devices for measuring the thickness of liquid films on rollers or cylinders · CPC title