Patent · US Expired

Apparatus and method for measuring the relative differential length in a sheet of material

US6178657A · kind A · utility

3Cited by
4References
4Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 31, 1998
Grant dateJan 30, 2001
Priority date
Expiry dateDec 31, 2018

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S33/02
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An apparatus for measuring the relative differential length of a sample of a web or sheet material. The apparatus includes a substantially flat surface adapted to support the sample. Air is removed between the sample and the substantially flat surface to position the sample in an unrestrained state. A translation member translates a plurality of non-contact sensors in a first direction along the length of the sample, whereby the plurality of non-contact sensors sense the distance from a reference plane to the sample and generate a signal representative of the distance sensed. A data collection system collects the generated signals and determines a relative differential length of the sample from the generated signals.

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