Patent · US Expired

Backlight sorting system and method

US5335791A · kind A · utility

42Cited by
15References
20Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 12, 1993
Grant dateAug 9, 1994
Priority date
Expiry dateAug 12, 2013

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S209/939
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A sorting apparatus according to the present invention includes a conveyor belt having a solid translucent sheet segment for carrying a stream randomly-arranged articles, ones of which are translucent and others of which are opaque. Preferably, the translucent articles are pieces of post-consumer plastic products (e.g., beverage containers) and the opaque articles are foreign matter, such as aluminum or polypropylene container tops or caps of the beverage containers. The conveyor belt carries multiple articles simultaneously through an inspection zone. A background light source is positioned in the inspection zone opposite the translucent sheet segment from the articles to direct light through the translucent sheet segment toward the articles. A video camera is positioned to receive light from the background light source transmitted through the translucent sheet segment and translucent ones of the articles. The opaque ones of the articles prevent light from the background light source from reaching the video camera. The video camera generates a video signal from which a system processor identifies the opaque articles and activates a separator to remove the opaque articles from the …

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.