Device for detecting elevations and/or depressions on bottles, in particular in a labeling machine

Patent metadata

Field	Value
Publication number	US-9533787-B2
Application number	US-77822610-A
Country	US
Kind code	B2
Filing date	May 12, 2010
Priority date	May 12, 2009
Publication date	Jan 3, 2017
Grant date	Jan 3, 2017

Abstract

A device for detecting elevations and/or depressions on bottles, in particular in a labeling machine, the device comprising a lighting unit with a light screen for generating a light reflection on a bottle to be examined and at least one camera for detecting the light reflection. By areas of varying luminance being formed on the light screen, molding seams can be reliably detected over a large area of the bottle wall and embossings can be located in various rotational positions of the bottle. The invention also relates to a method for applying the device.

First claim

The invention claimed is:

1. An inspection device for detecting elevations and/or depressions on bottles, in particular in a labeling machine, comprising:
a lighting unit with a light screen for generating a light reflection on a bottle to be examined;
at least one camera for imaging the bottle and the light reflection, the bottle specularly reflecting the light from the light screen so that the light reflection from the bottle constitutes a distorted image of the light screen;
a transport means moving the bottle through an image-recording area of the camera; and
a rotating support arranged on the transport means for fixing the bottle on the support and for rotating the bottle into predetermined rotational positions;
the light screen comprising areas of varying brightness, and being embodied as one or more of:
at least one light source and a diffusion screen having areas of varying light transmission,
at least one light source and foil having areas of varying light transmission, and
a matrix of light sources emitting light at different levels of brightness,

wherein the transition between the areas of varying brightness across the light screen is a gradual transition corresponding to a waved pattern, the areas of varying brightness alternating in a horizontal direction with respect to the bottle.

2. The inspection device according to claim 1 , wherein the areas of varying brightness are arranged in a stripe pattern.

3. The inspection device according to claim 2 , characterized in that the stripe pattern comprises two to four dark stripes.

4. The inspection device according to claim 1 , wherein the light screen comprises at least one foil in and/or on which the areas of varying brightness are formed.

5. The inspection device according to claim 4 , wherein the lighting unit comprises at least one light source, the light screen further comprises a diffusion screen, and the foil is arranged between the light source and the diffusion screen.

6. The inspection device according to claim 1 , wherein the light screen has the shape of a funnel opened towards the bottle.

7. The inspection device according to claim 1 , wherein the camera is inclined towards the bottom of the bottle and its optical axis includes an angle (a) of maximally 80° with the main axis of the bottle.

8. The inspection device according to claim 1 , further comprising:
a calculation unit for evaluating the detected reflection, for locating the elevations and/or depressions, and for determining an actual rotational position (φ I ) of the bottle.

9. The inspection device of claim 1 , wherein at least one camera captures an image of the bottle to be examined and the light reflection, and
wherein the transition between the areas of varying brightness across the light screen causes the light reflection to have areas of gradual transitions of brightness in the horizontal direction to facilitate band pass filtering as the image is evaluated.

Assignees

• Kwirandt Rainer
• Krones Ag

Inventors

• Kwirandt Rainer

Classifications

• B65C9/067 Primary

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• G01N21/9045

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• G01N21/9036

  using arrays of emitters or receivers · CPC title

• G01N2021/8832

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