Patents Assigned to Oy Finnpulva AB
  • Patent number: 5143303
    Abstract: A method and a equipment for processing of particularly finely divided material. The material is fed by means of a mechanical feeder device (2) and a pressurized equalization tank (4) into a fluidization chamber (5). A fluidized gas-solids suspension received is accelerated through acceleration nozzles (20) into a grinding chamber of a counter-jet grinder (19) so as to grind the solid particles. The ground gas-solids suspension is passed through connecting pipe (7) into a centrifugal classifier (8). A fine fraction is removed as a gas suspension through an opening (9). Additional air of low pressure is passed into the connecting pipe (7) and the coarse fraction is removed from the centrifugal classifier through a removal opening (10) in the peripheral face of the classifier into a pocket (12) outside said peripheral face, whereby the coarse fraction in the pocket (12) is removed batchwise by means of a closing device (13).
    Type: Grant
    Filed: May 23, 1991
    Date of Patent: September 1, 1992
    Assignee: Oy Finnpulva AB
    Inventor: Jouko Niemi
  • Patent number: 4919339
    Abstract: The invention concerns a method and an apparatus for improving the grinding result of a pressure chamber grinder. According to the method the finely divided material to be ground is fed by means of a mechanical feeder device (1) into a pressurized equalizing tank (2), the possibly clodded material is made loose by means of a rotor in the equalizing tank, and the material thus made loose is transferred into a pre-grinder (3), wherein several grinding-gas jets are applied to the material to be ground so that the material to be ground is fluidized, the fluidized material-gas flow is passed into a bisecting device (6), wherein it is divided into two component flows of equivalent magnitude and composition, each component flow is passed into the main grinding chamber (9) through a long accelerating nozzle (8) of its own, which said nozzle is directed so that a collision zone for the two component flows is formed in the center point of the said main grinding chamber.
    Type: Grant
    Filed: October 31, 1988
    Date of Patent: April 24, 1990
    Assignee: Oy Finnpulva AB
    Inventor: Jouko Niemi
  • Patent number: 4811907
    Abstract: A method and apparatus for improving the grinding result of a pressure chamber grinder includes a feeder for feeding material into a pressurized equalizing tank, then transferring the material into a pre-grinder where the material is fluidized by grinding-gas jets. The fluidized material-gas flow is divided by a bisecting device into two component flows and it is accelerated through two accelerating nozzles which are directed toward a impact point of a main grinding chamber. The grinding chamber has an outlet connected to an acceleration tube inlet which is connected at its discharge to a free-flow grinder provided with tangentially directed grinding-gas nozzles. The material which passes through the nozzles is in a ready ground final product form is removed constantly through a centrally located exhaust pipe.
    Type: Grant
    Filed: July 24, 1987
    Date of Patent: March 14, 1989
    Assignees: OY Finnpulva AB, Kemira OY
    Inventors: Jouko Niemi, Kaarlo Pyoria, Heikki Korhonen
  • Patent number: 4768721
    Abstract: The present invention is concerned with a grinder housing of a pressure chamber grinder, which said grinder housing comprises a substantially cylindrical outer mantle (1), end walls (2, 3), at least two accelerating nozzles (4) passing radially through the outer mantle (1), between which said nozzles there is an obtuse angle, as well as a discharge opening (5) made into one of the end walls (3) for the ground product.
    Type: Grant
    Filed: April 30, 1987
    Date of Patent: September 6, 1988
    Assignee: Oy Finnpulva AB
    Inventor: Jouko Niemi
  • Patent number: 4720049
    Abstract: The present invention is concerned with a device for feeding a material to be ground into a pressure chamber grinder provided with an equalizing tank (1), in which said equalizing tank (1) there is substantially the same pressure as in the pre-grinding part of the grinder, with which said pre-grinding part the equalizing tank (1) communicates via screw conveyor. The said device is installed in the top portion of the equalizing tank.
    Type: Grant
    Filed: June 5, 1986
    Date of Patent: January 19, 1988
    Assignee: Oy Finnpulva AB
    Inventor: Jouko Niemi