Method and apparatus for examining fiber material traveling in a fiber processing machine

DETAILED DESCRIPTION 1.
An apparatus for evaluating a fiber web running in a card, comprising: (a) a camera for scanning the fiber web along a length and width portion thereof to detect useful fibers and empty locations in the fiber web and to generate signals representing the useful fibers and empty locations; and (b) evaluating means connected to said camera for determining a distribution of useful fibers per area unit in the fiber web from the signals.
2.
A method of evaluating a fiber web running in a card, comprising the following steps: (a) scanning with a camera the fiber web along a length and width portion thereof; (b) detecting useful fibers and empty locations in the fiber web by the camera; (c) generating signals representing the useful fibers and empty locations; (d) applying the signals to an evaluating device connected to the camera; and (e) determining, by the evaluating device, a distribution of useful fibers per area unit in the fiber web from the signals.
3.
The method as defined in claim 2, further comprising the step of determining a numerical distribution of the useful fibers.
4.
The method as defined in claim 2, further comprising the step of determining a spatial distribution of the useful fibers.
5.
The method as defined in claim 2, further comprising the step of detecting impurities.
6.
The method as defined in claim 5, further comprising the step of distinguishing the impurities from the useful fibers.
7.
The method as defined in claim 2, further comprising the step of determining an area share of useful fibers and empty locations per unit area.
8.
The method as defined in claim 2, further comprising the step of determining a distribution of dense and thin areas of useful fibers per unit area.
9.
The method as defined in claim 8, further comprising the step of comparing said distribution with stored comparison values for the fiber web.
10.
The method as defined in claim 8, further comprising the step of comparing said distribution with a homogeneous fiber web.
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