Fast CD and MD control in a sheetmaking machine
US6080278A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 27, 1998 |
| Grant date | Jun 27, 2000 |
| Priority date | — |
| Expiry date | Jan 27, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S162/11
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A system and method of providing fast machine direction (MD) and cross direction (CD) basis weight adjustments using a simultaneous multi-point water weight sensor which provides independent MD and CD measurements is described. The water weight sensor is placed under the wire of the sheetmaking machine and provides fast wet end water weight measurements which are converted into predicted dry end basis weight information and used to control operating variables of machine elements in the sheetmaking machine to compensate for high frequency process variations. MD wet end measurements are used to control operating variables of machine elements that influence the MD dry end basis weight and CD wet end measurements are used to control operating variables of machine elements that influence CD dry end basis weight. The fast control information provided by the non-scanned water weight sensor can be used in a fast control loop which provides feedback information to wetstock source, headbox and forming elements and which can be used with a slower response control loop including a dry end sensor which provides a slower basis weight measurement and which controls system variables to compensate …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.