Title:
【発明の名称】長網抄紙機におけるドライラインの制御のため又は該ドライラインに基づいた制御のための方法及び装置
Document Type and Number:
Japanese Patent JP3119875
Kind Code:
B2
Abstract:
PCT No. PCT/FI92/00161 Sec. 371 Date Nov. 18, 1993 Sec. 102(e) Date Nov. 18, 1993 PCT Filed May 22, 1992 PCT Pub. No. WO92/20861 PCT Pub. Date Nov. 26, 1992.The system effects an automatic observation of the dry line on wire of the Fourdrinier paper machine and the control actions based on it. In order to produce an image of the dry line range on wire this is illuminated by means of a large, diffusely illuminating surface (20) of even luminosity. The material on moving wire (10) is imaged by an optoelectric camera (40) on a detector whereby the pulp surface preceding the dry line and being specularly reflecting is found homogeneous and bright while the web surface following it and being diffusely reflecting is found homogeneous but matter and darker. The electric image signal delivered by the detector is conducted to a computer (50) in which the dry line is identified as the borderline of said surfaces of different brightness. Its deviations from target values are determined for both the average value and different values in cross direction and the corresponding actuators are adjusted in order to control the paper web on the basis of deviations observed for its different parts or for its whole breadth. Dry line and values of quantities and deviations characterizing it are also presented on a display terminal, whereby said controls can alternatively be effected by a human observer.
Inventors:
Niemi, Anti Johannes
Application Number:
JP50981392A
Publication Date:
December 25, 2000
Filing Date:
May 22, 1992
Export Citation:
Assignee:
Niemi, Anti Johannes
Niemi, Uralita Anneli
Niemi, Uralita Anneli
International Classes:
D21F7/06; D21G9/00; D21F7/00; G01N21/57; (IPC1-7): D21F7/06; D21F7/00
Domestic Patent References:
| JP53147801A | ||||
| JP5227810A | ||||
| JP2501836A |
Other References:
【文献】英国特許出願公開1360992(GB,A)
Attorney, Agent or Firm:
Shuji Iwamiya