Photoelectric paper basis weight sensor
US5138178A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 17, 1990 |
| Grant date | Aug 11, 1992 |
| Priority date | — |
| Expiry date | Dec 17, 2010 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S177/06
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A non-contact, transmissive energy sensor is utilized for determining the thickness of paper sheets in a feed path. The sensor includes an energy emitting source and an energy detector, the output of the energy detecting source being proportional to the amount of energy received by the energy detector. The signal output level of the detector is utilized in a model to determine the basis weight of paper in the detecting zone of the detector. Heuristic sampling techniques can be utilized to reduce or eliminate the effects of images printed on the paper and flutter of the paper as it moves. An automatic calibration routine utilizing boundary coefficients is used to calibrate the paper basis weight detection system. The paper basis weight determination is utilized to control subsequent operations to which the paper sheet is subjected in order to optimize image quality and sheet handling, and to control finishing operations.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.