Doubles and thickness detector and sorter
US4121716A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 12, 1977 |
| Grant date | Oct 24, 1978 |
| Priority date | — |
| Expiry date | Dec 12, 1997 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB65H7/12
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
An automatic doubles and sheet thickness detector is disclosed that operates by comparing consecutive sheet materials that are delivered to a rotating drum. The consecutive sheet materials pass under two spaced apart rollers that are movably biased against the drum. If a sheet of greater thickness or a double sheet passes under one of the rollers, it will be displaced a greater distance from the drum surface than the other roller. This displacement is magnified by means of elongated pivot arms, which are attached to each roller. The magnified movement is detected by means of an optical arrangement comprising a light source, a photodetector, and a pair of mirrors. The mirrors are each secured to a distal end of a respective pivot arm. The light source casts a beam that reflects off each mirror towards the photodetector. When one of the arms is displaced more than its companion arm, such as when a double or thicker sheet lies between one of the rollers and the drum, the light beam will not be directed towards the photodetector. If each arm is displaced a like amount, as when consecutive single sheets are of like thickness, the photodetector will receive the reflected light, and there…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.