(19) |
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(11) |
EP 0 421 968 A3 |
(12) |
EUROPEAN PATENT APPLICATION |
(88) |
Date of publication A3: |
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01.04.1992 Bulletin 1992/14 |
(43) |
Date of publication A2: |
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10.04.1991 Bulletin 1991/15 |
(22) |
Date of filing: 01.10.1990 |
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(51) |
International Patent Classification (IPC)5: D21D 1/22 |
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(84) |
Designated Contracting States: |
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AT DE FR GB IT SE |
(30) |
Priority: |
05.10.1989 FI 894732
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(71) |
Applicant: SUNDS DEFIBRATOR JYLHÄ OY |
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SF-37601 Valkeakoski (FI) |
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(72) |
Inventor: |
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- Lumiainen, Jorma
SF-37630 Valkeakoski (FI)
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(74) |
Representative: Roth, Ernst Adolf Michael et al |
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GÖTEBORGS PATENTBYRA AB
Box 5005 S-402 21 Göteborg S-402 21 Göteborg (SE) |
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(57) A conical refiner for the refining of paper pulps or the like, comprising a stationary
stator blade (2) and a rotating rotor blade (1), with a refining zone (6) formed between
the blades so that one end of the refining zone opens to the pulp infeed side and
the other end to the delivery side of the refiner. A drawback with currently used
refiner constructions is that the pulp fed into the refiner is not refined uniformly,
so that the pulp flowing out of the refiner contains both refined fibres and fines
and unrefined fibres. In prior art, these have been screened only after the refining.
In the present invention, the refiner is provided with a screening unit (4, 7) working
on the principle of a pressure screen, the screen plate (4) of the screening unit
being of an essentially cylindrical form and coaxial with the refiner blades (1, 2),
said screening unit being fixedly connected to the stator blade and located at a desired
point in the direction of the pulp flow. The rotor blade (1) has a cylindrical shape
in the region of the pressure screen (4, 7) and is provided with a component (3) producing
the driving power for the pressure screen.
