Paper making and fiber liberation – Processes and products – With measuring – inspecting and/or testing
Reexamination Certificate
2008-01-15
2008-01-15
Hug, Eric (Department: 1731)
Paper making and fiber liberation
Processes and products
With measuring, inspecting and/or testing
C162S259000, C162S262000, C162S263000, C162SDIG010
Reexamination Certificate
active
07318882
ABSTRACT:
In order to observe the dry line formed on the surface of wood fibre pulp on the moving wire in a Fourdrinier paper machine, its—atrea of appearance is scanned at a low angle with a thin beam cluster (A1,B1) which, being generated by a laser radiation source (20) and representing one or more discrete wavelengths, is distinguishable from the background light. Hereby the surface following the dry line (I) reflects diffusively a major part and specularly a minor part of the arriving radiation than the surface preceding it. A detector (30) located above the level of the wire observes the intensity of the diffusely reflected radiation (A3,B3) hitting it and delivers continuously, as the beam cluster scans the pulp surface, a signal which is proportional to said intensity. The signal is digitized repeatedly and processed in real time in a computer, whereby a series of signals in the direction of the paper machine produces one dry line point and, if repeated for different positions in the cross direction, the dry line consisting of such points. The dry line and the values of quantities and deviations characterizing it are displayed by graphical and numerical terminals and actuators of the paper machine are controlled according to it automatically, synchronously with the scanning of the dry line region. The method can be implemented also in such paper machine environments, to which the earlier methods for structural reasons do not apply.
REFERENCES:
patent: 4500968 (1985-02-01), Bialkowski
patent: 5011573 (1991-04-01), Niemi
patent: 5472571 (1995-12-01), Niemi
patent: 5492601 (1996-02-01), Ostermayer et al.
patent: H001616 (1996-12-01), Wolfe
patent: 6053040 (2000-04-01), Callender et al.
patent: 10114638 (1977-07-01), None
patent: 751094 (1975-10-01), None
patent: 75887 (1986-12-01), None
patent: 88/05099 (1988-07-01), None
patent: 92/20861 (1992-11-01), None
Proceedings of Control System 2002 Conference, Stockholm, Jun. 3-5, 2002, pp. 308-312.
Cover page of book “Laser Beam Scanning”, Marcel Dekker, Inc. 1985.
J. Berndtson, A.J. Niemi & S. Karine, In Proceedings of 27th Eucepa Conf., Grenoblé, Oct. 1999.
Hug Eric
Jordan and Hamburg LLP
LandOfFree
Method and apparatus for monitoring of the dry line in a... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for monitoring of the dry line in a..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for monitoring of the dry line in a... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2756245