Device for detecting a position of a printing material transported in a printing machine

Patent metadata

Field	Value
Publication number	US-10328725-B2
Application number	US-201715718008-A
Country	US
Kind code	B2
Filing date	Sep 28, 2017
Priority date	Sep 30, 2016
Publication date	Jun 25, 2019
Grant date	Jun 25, 2019

Abstract

A device detects at least one position of at least a part of a printing material while the printing material is transported in a printing machine. The device includes an optical sensor for establishing a distance between a printing machine component and the printing material. The distance established by the optical sensor is temperature-compensated by a computer.

First claim

The invention claimed is:

1. A device for detecting at least one position of at least a part of a printing material while the printing material is transported in a printing machine, the device comprising:
an optical sensor for establishing a distance between a printing machine component and the printing material; and
a computer for temperature-compensating the distance established by said optical sensor;
said computer saving an intensity pattern of said optical sensor on said computer, and said intensity pattern representing a measurement uninfluenced by external temperatures;
said computer comparing an intensity pattern established by said optical sensor under thermal influences and said saved intensity pattern without thermal influence; and
said computer calculating said thermal influence and compensating for said thermal influence in a computational way based on a deviation between said two patterns.

2. The device according to claim 1 , which further comprises:
a light source emitting light beams in a beam path in a direction toward said optical sensor;
at least parts of the printing material being located in said beam path between said light source and said optical sensor; and
said optical sensor being a CCD line sensor including a plurality of CCD elements.

3. The device according to claim 2 , wherein said light source includes a lens to widen an illumination in parallel.

4. The device according to claim 2 , wherein said light source is dot-shaped.

5. The device according to claim 2 , which further comprises a cover plate disposed between said light source and said optical sensor.

6. The device according to claim 1 , wherein said computer compares a height difference between a first local maximum of said saved intensity pattern and a first local maximum of said measured intensity pattern in said comparison of said intensity patterns carried out on said computer.

7. The device according to claim 1 , which further comprises a temperature control device for controlling a temperature of at least parts of the printing machine in a region of a measuring process.

8. The device according to claim 1 , wherein said computer switches the printing machine off when a measured distance between said optical sensor and the printing material exceeds a predefined value.

9. The device according to claim 8 , wherein said predefined value is a temperature-dependent switch-off threshold.

10. A device for detecting at least one position of at least a part of a printing material while the printing material is transported in a printing machine, the device comprising:
an optical sensor for establishing a distance between a printing machine component and the printing material;
a computer for temperature-compensating the distance established by said optical sensor, said computer saving an intensity pattern of said optical sensor on said computer, and said intensity pattern representing a measurement uninfluenced by external temperatures; and
at least one temperature sensor for measuring a temperature of grippers of the printing machine for transporting sheet-shaped printing materials, said at least one temperature sensor transmitting said measured temperature to said computer.

Assignees

• Heidelberger Druckmasch Ag

Inventors

• Knauf Stefan
• Henn Andreas
• Ritz Juergen
• Lorenz Olaf
• Schmidt Thomas
• Muench Stefan
• Goebel Thomas
• Kabus Wolfgang
• Weinig-Kress Stephanie
• Mutschall Stefan
• Norrick Nicklas Raymond
• Neeb Steffen

Classifications

• 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

• G01J2005/068

  Physics · mapped topic

• G06K15/1219

  Detection, control or error compensation of scanning velocity or position, e.g. synchronisation (G06K15/1223 takes precedence) · CPC title

• G01J5/06

  Arrangements for eliminating effects of disturbing radiation; Arrangements for compensating changes in sensitivity (for adjusting of solid angle of collected radiation G01J5/07; means for wavelength selection G01J5/0801) · CPC title

• B41J2/1408

  Structure dealing with thermal variations, e.g. cooling device, thermal coefficients of materials · CPC title