Method and calibration tool for calibrating a rotary printing press

1. A method for calibrating a position of a printing cylinder in a rotary printing press, wherein a bearing structure for the printing cylinder is adjusted relative to another component of the printing press, and positions of the bearing structure are measured, the printing cylinder comprising a mandrel that is supported in the bearing structure, and a printing adapter removably mounted on the mandrel, the method comprising the steps of:

replacing a printing adapter by mounting a calibration tool on the mandrel, the calibration tool having at least one sensor embedded in the calibration tool such that a sensitive part of the at least one sensor is exposed in a peripheral surface of the calibration tool,

detecting an angular reference position of the calibration tool by an inclinometer provided in the calibration tool,

rotating the calibration tool into an angular position in which the sensitive part of the at least one sensor will contact or detect proximity to a peripheral surface of the other component when the calibration tool is moved into contact with or proximity to the other component,

moving the bearing structure until the at least one sensor detects contact with or proximity to the other component, and sends a signal to a controller,

upon detection of the signal from the at least one sensor, storing a measured position of the bearing structure as a reference position, and

replacing the calibration tool by a printing adapter and using the stored position of the bearing structure to position the printing cylinder in the printing press.

2. The method according to claim 1 , wherein the other component of the printing press is one of:

a central impression cylinder and

an anilox roller.

3. The method according to claim 2 , further comprising the steps of:

moving opposite ends of the calibration tool against one of:

the central impression cylinder and

the anilox roller

independently of one another, and

storing independent reference positions on the basis of sensor signals from two sensors of said at least one sensor arranged at opposite ends of the calibration tool.

4. The method according to claim 2 , further comprising the steps of:

when the calibration tool engages one of the central impression cylinder and the anilox roller, detecting an angular position of one of the central impression cylinder and the anilox roller and

establishing a relation between the angular position of one of the central impression cylinder and the anilox roller and an angular position of the calibration tool by detecting an offset between a reference mark and a mark detector that are provided on a peripheral surface of one of the central impression cylinder and the anilox roller and the peripheral surface of the calibration tool, respectively.

5. The method according to claim 1 , wherein at least one sensor is mounted in an end face of the calibration tool and the other component of the printing press is a frame member.

6. The method according to claim 1 , for a printing press having a detector arranged for detecting a reference mark on the printing cylinder, comprising a step of detecting a reference mark on the calibration tool with said detector.

7. The method according to claim 1 , wherein the at least one sensor is at least one contact-sensitive switch.

8. The method according to claim 1 , wherein the at least one sensor is at least one distance detector.