Patent · US Expired

Method and apparatus for detecting thickness variation in sheet material

US5317898A · kind A · utility

18Cited by
12References
7Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 11, 1992
Grant dateJun 7, 1994
Priority date
Expiry dateDec 11, 2012

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB65H2511/51
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

The detection of thickness variations in sheet material, more specifically the presence or absence of labels on a moving web, is accomplished by providing two spaced apart nozzles, an entry for pressurized fluid, first and second conduits to connect the entry and the nozzles, and a differential pressure sensing element connected between the conduits so as to detect a mismatch between the fluid pressures in the two conduits.

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