Patent EP0189985A1 successfully refreshed from Google Patents.
EP0189985A1
Expired / Lapsed
EP
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Web monitoring arrangement
Assignee: Haigh Chadwick Ltd
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Filing: 1986-01-15
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Granted: —
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Expires: 2006-01-15
Abstract
Abstract 57 A fibre web monitoring arrangement for travelling card and like webs (11) comprises an elongate light source (12) such as a fluorescent tube arranged transversely of the direction of web travel and, on the opposite side of the web path, a series of spaced apart photosensitive devices (14) illuminated through the web (11) by the light source (12) and indicating means for indicating the level of illumination of the said devices (14) as an indication of web density.
Inventors
- 👤 David Brunnschweiler
- 👤 Neil Rutherford Henderson
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 02:26
CPC Classifications
D; D01; D01G; D01G31/00; D01G31/006; G; G01; G01N; G01N21/00; G01N21/84; G01N21/88; G01N21/89; G01N21/8901; G01N21/8903
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
76 words
A web monitoring arrangement for travelling card and like webs comprising an elongate light source arranged transversely of the direction of travel of the web so as to illuminate the web uniformly thereacross and, on the opposite side of the web path, a series of spaced apart photosensitive devices illuminated through the web by the light source and indicating means for indicating the level of illumination of the said devices as an indication of web density.
Claim 2
Dependent Claim
76 words
A web monitoring arrangement for travelling card and like webs comprising an elongate light source arranged transversely of the direction of travel of the web so as to illuminate the web uniformly thereacross and, on the opposite side of the web path, a series of spaced apart photosensitive devices illuminated through the web by the light source and indicating means for indicating the level of illumination of the said devices as an indication of web density.
Claim 3
Dependent Claim
24 words
An arrangement according to claim 1, in which the light source comprises a fluorescent tube extending across the web from side of side thereof.
Claim 4
Dependent Claim
12 words
An arrangement according to claim 2, said fluorescent tube having a diffuser.
Claim 5
Dependent Claim
16 words
An arrangement according to any one of claims 1 to 3, said photosensitive devices comprising photodiodes.
Claim 6
Dependent Claim
22 words
An arrangement according to any one of claims 1 to 4, said photosensitive devices being spaced apart uniformly across the web path.
Claim 7
Dependent Claim
15 words
An arrangement according to claim 5, said photosensitive devices being spaced apart by about 10cm.
Claim 8
Dependent Claim
32 words
An arrangement according to any one of claims 1 to 6, said indicating means being adapted to display signals from said photosensitive devices individually whereby to indicate web density in specific areas.
Claim 9
Dependent Claim
39 words
An arrangement according to claim 7, said indicating means comprising a bar chart display having as many channels as there are photosensitive devices and arranged correspondingly so as to give a visual indication of density distribution across the web.
Claim 10
Dependent Claim
15 words
An arrangement according to claim 8, said bar chart display comprising liquid crystal display means.
Claim 11
Dependent Claim
36 words
An arrangement according to any one of claims 1 to 9, said indicating means being adapted to integrate signals from said photosensitive devices so as to give an indication of average web density across the web.
Claim 12
Dependent Claim
42 words
An arrangement according to any one of claims 1 to 10, in which an output signal indicative of average web density is used to control a carding or other machine producing a web so as to maintain the indicated web density constant.
Claim 13
Dependent Claim
20 words
An arrangement according to claim 11, in which the output signal controls feed rollers supplying fibre to a carding machine.
Claim 14
Dependent Claim
24 words
1 3 . An arrangement according to any one of claims 1 to 12, in which the light source is situated below the web.
Claim 15
Dependent Claim
22 words
An arrangement according to any one of claims 1 to 13, in which the web is arranged to wipe the light source.
Claim 16
Dependent Claim
28 words
An arrangement according to any one of claims 1 to 14, comprising air jet means associated with the photoelectric devices adapted to prevent build up of obscuring material.
Claim 17
Dependent Claim
59 words
An arrangement according to any one of claims 1 to 15, comprising photodiode calibration means comprising digital electronic circuitry storing data representative of the output voltages of each diode in a test with no web present at two different light levels and applying a correction factor (assuming the response of each diode to be linear over the illumination range).
References Cited (Backward Citations)
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