Patent · US Expired

Method of and apparatus for making a rod of fibrous material

US4860772A · kind A · utility

6Cited by
9References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 26, 1988
Grant dateAug 29, 1989
Priority date
Expiry dateMay 26, 2008

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S131/906
  • WIPO fieldOther consumer goods
  • WIPO sectorOther fields

Abstract

A shower of fibrous material is directed against the underside of the lower reach of a foraminous endless belt conveyor so that the fibrous material gathers into a continuous stream which is attracted to the conveyor by suction and is moved longitudinally past a trimming device which removes the surplus. The density of the stream is monitored upstream and downstream of the trimming device, and the corresponding signals are processed in an evaluating circuit into additional signals which are indicative of the quantity of the removed surplus. The removed surplus is weighed and the weighing device generates signals also denoting the quantity of the surplus. Such signals are compared with the additional signals and further signals, which denote the differences between the intensities of the compared signals, are used to modify signals denoting the density of the stream downstream of the trimming device. The thus modified signals are used to adjust the trimming device. This ensures that, if the density monitoring operation is carried out by detectors employing sources of infrared light, signals which are generated by such detectors are not affected by certain variable parameters of the …

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