Method for accurately counting conveyed workpieces regardless of variations in conveyor speed
US5614709A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 1, 1995 |
| Grant date | Mar 25, 1997 |
| Priority date | — |
| Expiry date | May 1, 2015 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB65H2301/541
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method for counting conveyed workpieces, such as on a variable speed conveyor belt, includes sensing interruptions via an object sensor such as an optical sensor with a light beam, and with a computer, applying a mathematical comparison between duration of interruptions to the light beam path and gaps that separate these interruptions. The comparison determines which interruptions are caused by the passage of conveyed workpieces and which interruptions are caused by the passage of other objects such as components of the conveyor belt. The method described involves the selection of a preset factor used in a ratio comparison between the duration of interruptions to the light beam and the gaps that separate these interruptions such that the computer is able to accurately count objects such as sheets of paper pulled by gripper bars and distinguishing between sheets of paper and gripper bars such that gripper bars and clips are not incorrectly counted as sheets of paper. Accuracy is not compromised by changes in speed of the conveyor. The gripper bars are fully filtered from the product count value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.