Device and method for contactless detection of characteristics of continuously delivered translucent products

• US 8,339,596 B2
• Filed: 02/20/2009
• Issued: 12/25/2012
• Est. Priority Date: 03/08/2008
• Status: Active Grant

• Current Assignee: Nordischer Maschinenbau Rud. Baader GmbH + Co. KG
• Original Assignee: Nordischer Maschinenbau Rud. Baader GmbH + Co. KG
• Inventors: Nilsen, Heidi Anita, Sivertsen, Agnar Holten, Heia, Karsten
• Primary Examiner(s): NGUYEN, SANG H
• Application Number:
  US12/919,825
• Publication Number:
  US 20110013181A1
• Time in Patent Office: 1,404 Days
• Field of Search: 3562391-2398, 3562381-2383, 356426-431, 250/225, 250/223.R, 250/391, 209/577, 209/587, 209/639, 209/938
• US Class Current: 356/239.1
• CPC Class Codes: G01N 21/8901 Optical details; Scanning details per se G02B
• CPC Class Codes: G01N 33/12 Meat; fish

Abstract

An apparatus for contactless detection of characteristics of continuously conveyed, translucent products includes first and second transmitting units each having an independent light source to generate high-intensity light radiation to illuminate the product, a light-converting element to form a planar light field from the light radiation and a focusing element to form a line of light running transversely to a direction of conveying of the products from the planar light field. A receiving unit has a detection device to pick up the light radiation transflected by the product. Shading elements are arranged respectively between the transmitting units and the receiving unit. The first transmitting unit is arranged in front of the receiving unit in the direction of conveying of the products and the second transmitting unit is arranged behind the receiving unit in the direction of conveying.

Claims

1. An apparatus for contactless detection of characteristics of continuously conveyed, translucent products, comprising:

first and second transmitting units each having

an independent light source to generate high-intensity light radiation to illuminate the product,

a light-converting element to form a planar light field from the light radiation, and

a focusing element to form a line of light from the planar light field, wherein the line of light extends transversely to a direction of conveying of the products and parallel to the line of light generated by the other transmitting unit, wherein the line of light and a center axis of the focussing element define a first plane perpendicular to the direction of conveying;

a receiving unit having a detection device to pick up the light radiation transflected by the product in an inspection region, wherein the line of light formed by each transmitting unit runs parallel to the inspection region, and wherein the detection device and the inspection region define a second plane parallel to the first plane; and

shading elements arranged respectively between the transmitting units and the receiving unit, wherein the first and second transmitting units are shielded from the receiving unit by the respective shading elements,

wherein the first transmitting unit is arranged in front of the receiving unit in the direction of conveying of the products and the second transmitting unit is arranged behind the receiving unit in the direction of conveying.

2. The apparatus according to claim 1, wherein the receiving unit is sandwiched between the shading elements which are directed vertically to a plane of conveying of the products.

3. The apparatus according to claim 1, wherein at least two shading elements are assigned to each transmitting unit such that the transmitting units are shielded by a shading element on either side.

4. The apparatus according to claim 1, wherein the focusing element comprises a cylindrical lens.

5. The apparatus according to claim 4, wherein the lens comprises poly(meth)acrylates.

6. The apparatus according to claim 4, wherein the lens has a diameter of 25 mm and a length of 200 mm.

7. The apparatus according to claim 4, wherein the lens is attached to the light-converting element.

8. The apparatus according to claim 4, wherein the lenses of the two transmitting units are oriented parallel to each other.

9. The apparatus according to claim 4, wherein the lenses have centre axes that are oriented transversely to the direction of conveying of the products.

10. The apparatus according to claim 1, wherein a distance between the two lines of light generated by the light sources or lenses is approximately 40 mm.

11. The apparatus according claim 1, wherein the detection device comprises a camera.

12. The apparatus according to claim 1, further comprising an evaluation unit assigned to the detection device.

13. The apparatus according to claim 1, wherein the light-converting element is constructed to form a rectangular light field.

14. The apparatus according to claim 1, further including a transport element for conveying the products, and wherein both transmitting units are arranged above the transport element.

15. A method for contactless detection of characteristics of continuously conveyed, translucent products, comprising the steps of:

continuously conveying the products through the inspection region of the detection device of the receiving unit of the apparatus of claim 1;

exposing the products to high-intensity light radiation from the independent light sources of the first and second transmitting units both on entering the inspection region and on leaving the inspection region of the detection device; and

picking up the light radiation transflected by the products by the receiving unit.

16. The method according to claim 15, wherein the exposing includes widening the high-intensity light radiation emanating from each of the light sources into the planar light fields by the light-converting elements and then focussing the planar light by the focusing elements into the lines of light running transversely to the direction of conveying of the products.

17. The method according to claim 15, including shielding the first and second transmitting units on at least two sides.

18. The method according to claim 15, including processing the transflected light radiation picked up by the receiving unit in an evaluating unit.

19. The apparatus according to claim 1, wherein the center axes of the focussing elements are oriented transversely to the direction of conveying, and wherein a distance between the center axes of the focusing elements is equal to a distance between the lines of light generated by the first and second transmitting units.