Patents Assigned to Maschinenfabrik Andritz Actiengesellschaft
  • Patent number: 4874468
    Abstract: The invention relates to an apparatus or plant or arrangement for the treatment of a dilute suspension of fibers or layer of material passed between two endless foraminous belts or wires or the like conveying means, the forming fibrous board being made to pass between the foraminous belts along at least one container for a treatment medium and at least some of the treatment containers being provided with a wall having orifices on the side facing the fibrous board for generating a pressure difference on the same, but being otherwise closed against the environment, and/or at least some of the treatment containers closed against the environment having walls closed against the foraminous belts and thus against the fibrous board, but otherwise open towards the foraminous belts. According to the invention, a reduction of the energy requirement in the displacement washing of filter cakes is sought above all.
    Type: Grant
    Filed: October 20, 1988
    Date of Patent: October 17, 1989
    Assignee: Maschinenfabrik Andritz Actiengesellschaft
    Inventors: Johann Sbaschnigg, Franz Petschauer
  • Patent number: 4863107
    Abstract: For removing foreign solids, for instance contaminants, from pulpers in which waste paper, in particular with a share of more than five percent, for instance more than ten percent, of solids foreign to paper, is pulped or suspended and the suspension or slurry is the withdrawn through a screen zone for further processing, it is proposed according to the invention to at least partially withdraw the suspension or slurry from the pulper in periodic time intervals and, subsequent to the, in particular each, partial withdrawal of the suspension or slurry, to loosen, hydrodynamically or by means of fluids, the foreign solids accumulated on one side, in particular the upper side, of the screen zone, whereupon the dirt slurry obtained by hydrodynamical loosening is fully mechanically discharged from the pulper prior to newly charging the pulper. The hydrodynamical loosening of the foreign solids is preferably effected under backflushing through the screen zone.
    Type: Grant
    Filed: April 15, 1987
    Date of Patent: September 5, 1989
    Assignee: Maschinenfabrik Andritz Actiengesellschaft
    Inventors: Erich Harzl, Karl Maier, Sirous Namdar
  • Patent number: 4851119
    Abstract: The invention relates to a machine for pressing or dewatering and filtering of suspensions, sludges and the like with at least one driven endless pressure belt and further in particular at least one circulating endless filter belt, the pressure belt serving for the support of the filter belt. For the exertion of surface pressure onto the pressure belt, at least one frame-like, resilient, elastic hollow pad or a resilient, elastic hollow frame is provided, their interior being suitable for the admission of pressure medium and the pad or frame enclosing a pressure space, with a gap being provided at least during the admission of pressure medium between the hollow pad or hollow frame and the pressure belt.
    Type: Grant
    Filed: August 12, 1987
    Date of Patent: July 25, 1989
    Assignee: Maschinenfabrik Andritz Actiengesellschaft
    Inventors: Dag Bergloff, Heinz Perchthaler, Reinhard Pinter
  • Patent number: 4851092
    Abstract: In a process for the electrolytic pickling of chromium-containing stainless steel, pickling proceeds initially in an aqueous Na.sub.2 SO.sub.4 solution and subsequently in acid, preferably mixed acid. The CrO.sub.4.sup.2- formed is converted by the addition of reducing agent and acid as a function of the pH value and the redox potential to Cr.sub.2 (SO.sub.3).sub.3 or Cr.sub.2 (SO.sub.4).sub.3. H.sub.2 SO.sub.4 serves as the acid and a substance is used as a reducing agent selected from the group Na.sub.x H.sub.y S.sub.z O.sub.v, wherein x=0 to 2, y=0 to 2, y=1 to 6 and v=2 to 6. The pH value is adjusted to less than three by the addition of acid.
    Type: Grant
    Filed: May 3, 1988
    Date of Patent: July 25, 1989
    Assignee: Maschinenfabrik Andritz Actiengesellschaft
    Inventor: Gerald Maresch
  • Patent number: 4848224
    Abstract: The invention relates to a press consisting of at least one, conveniently perforated and hollow, rotatable drum as well as press rollers with axes parallel in relation to the drum axis acting against the outer shell of the drum, with at least one web of material to be pressed made to pass between said drum and the aforementioned rollers, conveniently supported by one of two screen belt(s) or the like.
    Type: Grant
    Filed: April 12, 1988
    Date of Patent: July 18, 1989
    Assignee: Maschinenfabrik Andritz Actiengesellschaft
    Inventors: Alexander Schubernig, Peter Blunegger
  • Patent number: 4849116
    Abstract: The invention relates to a process and a plant for separating low density material, in particular plastics, in particular with a density of less than 1, from substrate mixtures, preferably from waste material fractions or presorted garbage fractions optionally containing essential portions of plastics or optionally presorted to paper/plastics fractions, wherein a gravity separation, in particular a sink-float separation, is carried out and the low density material phase, in particular polyolefin plastics, is withdrawn and optionally further processed as a separate fraction after drying.According to the invention, the separating effect and the cleaning of the low density material phase withdrawn are increased by carrying out at least one centrifugal separation, preferably in a hydrocyclone, in addition to at least one gravity separation, preferably in a sink-float basin.
    Type: Grant
    Filed: May 27, 1987
    Date of Patent: July 18, 1989
    Assignee: Maschinenfabrik Andritz Actiengesellschaft
    Inventors: Alfred Weinmann, Josef Steinegger, Peter Scheucher, Roland Konstantiniuk, Wolfgang Leutzendorff, Hubert Hermann
  • Patent number: 4840385
    Abstract: The invention relates to a device for sealing shaft bearings or shaft bearing housing, in particular of self-aligning roller bearings for prepressing rollers or the like, having a special ring or special sleeve which surrounds the shaft, is advantageously made of stainless steel and has on the outer circumferential surface at least one annular projection which extends into at least one annular groove at at least one end of the bearing housing. According to the invention the concern here is primarily to inexpensively develop bearing housings, in particular production bearing housings, for operating conditions with exacting requirements on the sealing of the bearing.
    Type: Grant
    Filed: September 21, 1987
    Date of Patent: June 20, 1989
    Assignee: Maschinenfabrik Andritz Actiengesellschaft
    Inventors: Helmut Senft, Peter Hasenrath
  • Patent number: 4812234
    Abstract: This invention relates to an improvement in the process for conditioning oil sludges, in which a wire cloth press is used as a separation device forming a pressed cake and including a sludge basin wherein mixing of individual sludges takes place and from which a suspension is removed, and further including intermediate stages for additions assuring the dehydration procedure, the improvement comprising adding structure-improving means to the suspension to increase the shear resistance of the pressed cake and to lower the filtration impedance. The invention also relates to equipment for performing the process.
    Type: Grant
    Filed: July 25, 1985
    Date of Patent: March 14, 1989
    Assignee: Maschinenfabrik Andritz Actiengesellschaft
    Inventors: Heinz Perchthaler, Stamatios Stefou
  • Patent number: 4789440
    Abstract: Process and apparatus for the continuous electrolytic treatment and/or coating of a moving metallic strip while changing the spacing between the strip and at least one electrode as a function of deviations (distortions) of the strip normal to the direction of movement of the strip in order to automatically maintain an optimal spacing so as to keep the voltage drop in the electrolyte low and save energy. For that purpose feeler means are provided to determine the deviation and generate a first signal. A second signal is generated as a function of the velocity of the strip. The period from the moment of detecting the deviation to the moment of its arrival at the electrode, reduced by the response period for changing the spacing, is computed. The period needed for passing through the electrode is computed.
    Type: Grant
    Filed: March 7, 1988
    Date of Patent: December 6, 1988
    Assignee: Maschinenfabrik Andritz Actiengesellschaft
    Inventors: Erich Mahr, Wilhelm Hofkirchner
  • Patent number: 4735700
    Abstract: Process and apparatus for the continuous electrolytic treatment and/or coating of a moving metallic strip whilst changing the spacing between the strip and at least one electrode as a function of deviations (distortions) of the strip normal to the direction of movement of the strip in order to automatically maintain an optimal spacing so as to keep the voltage drop in the electrolyte low and save energy. For that purpose feeler means are provided to determine the deviation and generate a first signal. A second signal is generated as a function of the velocity of the strip. The period from the moment of detecting the deviation to the moment of its arrival at the electrode, reduced by the response period for changing the spacing, is computed. The period needed for passing through the electrode is computed.
    Type: Grant
    Filed: March 11, 1987
    Date of Patent: April 5, 1988
    Assignee: Maschinenfabrik Andritz Actiengesellschaft
    Inventors: Erich Mahr, Wilhelm Hofkirchner
  • Patent number: 4681659
    Abstract: A multi-nip high pressure press is disclosed, which can be connected to double, longitudinal or circular strainer machines but where this press is a single machine, using an additional pressing segment including at least one pair of rollers of lesser diameters mounted in advance of a pair of compression rollers.
    Type: Grant
    Filed: October 4, 1985
    Date of Patent: July 21, 1987
    Assignee: Maschinenfabrik Andritz Actiengesellschaft
    Inventor: Johann Sbaschnigg
  • Patent number: 4612123
    Abstract: This invention relates to an improvement in a regulating apparatus for a dewatering machine, in particular a double strainer dewatering machine (sieve belt press), with one or more control circuits, for instance a flocculant control circuit and/or a flow rate control circuit, or a straining rate control circuit, to adapt to sludges or suspensions with varying dewatering properties, the improvement comprising means employing the rate of freely draining filtrate in the strainer zone as the criterion value for the flocculant control circuit.
    Type: Grant
    Filed: January 22, 1985
    Date of Patent: September 16, 1986
    Assignee: Maschinenfabrik Andritz Actiengesellschaft
    Inventors: Peter Eustacchio, Heinz Perchthaler, Rupert Syrowatka
  • Patent number: 4544447
    Abstract: The invention relates to an improvement in a dehydration machine for wood pulp, sludges, or similar fibrous material, composed of a lower strainer operating as a support strainer and an upper strainer operating as the cover strainer, which loop support and reversing rolls and are adapted to pass jointly with the material to be dehydrated coming from a material feed through a wedging section and through pairs of pressing rolls in a pressing section, the improvement comprising a laterally sealed wedging section arranged substantially vertically or at an incline, followed directly by a reversal means provided with a lateral seal, and the pressing section including a group of rolls which at the beginning contains a pair of first and second pressing rolls mounted next to each other, with a pressing roll contacting the second pressing roll.
    Type: Grant
    Filed: July 27, 1983
    Date of Patent: October 1, 1985
    Assignee: Maschinenfabrik Andritz Actiengesellschaft
    Inventors: Reinhard Pinter, Franz Petschauer, Johann Sbaschnigg
  • Patent number: 4509274
    Abstract: In equipment for drying lengths of materials, in particular lengths of paper, with the length being guided by means of a permeable belt in a semi-circle around a drying drum and being deflected by a guide roller toward a next drying drum which is enveloped in the same manner, with blow boxes being arranged between the drums to supply the drying medium, the improvement comprising means mounting blow-out sections (7) of the blow boxes (3) in a displaceable manner in the radial direction of the drying drums (1, 2) within a frame (12), and means whereby the sections can be returned into their initial positions.
    Type: Grant
    Filed: December 21, 1982
    Date of Patent: April 9, 1985
    Assignee: Maschinenfabrik Andritz Actiengesellschaft
    Inventors: Helmut Heimel, Willy Schlosser, Alfred Luttenberger
  • Patent number: 4481118
    Abstract: Disclosed are methods and apparatus for rinsing soluble materials from the filter cake formed in a double belt press. The belts with the filter cake therebetween are suspended between two spaced apart rollers to relieve pressure on the filter cake and the filter cake is simultaneously exposed to a rinse medium. Pressure is thereafter re-applied to the filter cake to extract the rinse medium therefrom.
    Type: Grant
    Filed: November 3, 1982
    Date of Patent: November 6, 1984
    Assignee: Maschinenfabrik Andritz Actiengesellschaft
    Inventors: Otto Heissenberger, Franz Petschauer, Johann Sbaschnigg
  • Patent number: 4262715
    Abstract: An improved decorticating drum with a selective mode of processing is disclosed, composed of a hollow cylinder horizontally resting on support rollers and being rotatable about its longitudinal axis, being adapted to receive wood fed in at one end and discharge it at the other, in particular a decorticating drum for dry debarking including longitudinal slots at the surface thereof for the elimination of the bark, the improvement comprises detachable covers in the region of the longitudinal slots whereby a wet decorticating drum may be formed, said covers resting against the outer surface of the drum.
    Type: Grant
    Filed: November 21, 1978
    Date of Patent: April 21, 1981
    Assignee: Maschinenfabrik Andritz Actiengesellschaft
    Inventors: Richard Hausler, Karl Krebs
  • Patent number: 4168580
    Abstract: This invention relates to an improvement in a drying installation for treating a web of material including a drying hood having flow channels therein and heat sources and blowers for the circulation of a drying medium which is passed through apertures to said web and drawn off again through exhaust channels, the improvement comprising a plurality of profiled tube means mounted adjacent said web, the distances between said tube means constituting diffuser-like gaps serving as exhaust channels, and a plurality of apertures in said tube means directed toward said web, said apertures being in a triangular configuration and distributed over said tube means at a constant distance.
    Type: Grant
    Filed: May 4, 1973
    Date of Patent: September 25, 1979
    Assignee: Maschinenfabrik Andritz Actiengesellschaft
    Inventor: Alfred Weinmann
  • Patent number: 3942584
    Abstract: This invention relates to an improvement in a hot water pump having a cooled sealing housing in a pump cover in the upper pump portion. The improvement comprises means mounting the sealing housing in a recess of the pump cover in a manner such that an annular air space is present between the outer surface of said sealing housing and the inner surface of the recess of the pump cover, said air space being in communication with the exterior space surrounding the pump.
    Type: Grant
    Filed: May 10, 1972
    Date of Patent: March 9, 1976
    Assignee: Maschinenfabrik Andritz Actiengesellschaft
    Inventor: Rudolf Wieser