Method and device for inspecting images on print products using an image inspection robot

Patent metadata

Field	Value
Publication number	US-11250556-B2
Application number	US-201916418218-A
Country	US
Kind code	B2
Filing date	May 21, 2019
Priority date	Jun 13, 2018
Publication date	Feb 15, 2022
Grant date	Feb 15, 2022

Abstract

A method for inspecting images on print products in a printing material processing machine includes recording and digitizing produced print products using at least one image sensor in an image inspection process of a print job using an image inspection system. The recorded digital prints that have been created are compared to a digital reference image by using a computer and, if deviations are found between the recorded digital prints and the digital reference image, print products found to be defective are removed. The image sensor records the produced print products from at least two different viewing angles and/or viewing distances and the computer evaluates the at least two recorded digital prints as a function of the at least two viewing angles and/or viewing distances and assesses them in terms of deviations. A device for inspecting images on print products is also provided.

First claim

The invention claimed is:

1. A method for inspecting images on print products in a printing material processing machine, the method comprising the following steps:
using at least one image sensor to record and digitize produced print products in an image inspection process of a print job carried out by an image inspection system, the image sensor recording the produced print products from at least one of different viewing angles or different viewing distances;
using a computer to compare at least two created and recorded digital prints to a digital reference image, the computer evaluating the at least two recorded digital prints as a function of the at least one of different viewing angles or different viewing distances and the computer assessing the at least two recorded digital prints in terms of deviations;
using the computer to control a robot arm having the image sensor by moving the robot arm back and forth during an image recording process to simulate a shaking motion of the printed product during the inspection process; and
removing defective print products upon finding deviations between the recorded digital prints and the digital reference image.

2. The method according to claim 1 , which further comprises taking the at least two different viewing angles into consideration from 0 to 180° both vertically in terms of elevation and horizontally in terms of azimuth.

Assignees

• Heidelberger Druckmasch Ag

Inventors

• Trachanas Ilias
• Fehlner Andreas

Classifications

• H04N1/00246 Primary

  with an optical device, e.g. an optical viewing aid · CPC title

• G06T7/001 Primary

  using an image reference approach · CPC title

• G06V10/993

  Evaluation of the quality of the acquired pattern · CPC title

• G06T2207/30144

  Printing quality · CPC title

• B41F33/0036

  Devices for scanning or checking the printed matter for quality control · CPC title