Patents by Inventor Jorma Laapotti

Jorma Laapotti has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4673462
    Abstract: A closed press section of a paper machine in which a paper web leaving the wire section of the paper machine is passed, supported by a first upper fabric, through a first double-felted press nip formed by two hollow-faced rolls. The lower fabric in the first double-felted press nip is a second fabric which carries the web forwardly after the first press nip. The press section further includes a smooth-faced central roll against which at least two single-felt nips are formed, the press fabric in the first one of the single-felt nips being constituted by the second fabric. The web is detached from the second fabric and adheres to the face of the smooth-faced central roll and moves along therewith into the next single-felt nip. The press section is devoid of press rolls of the suction type with the first double-felted press nip being formed between two solid-mantle hollow-faced rolls.
    Type: Grant
    Filed: April 2, 1985
    Date of Patent: June 16, 1987
    Assignee: Valmet Oy
    Inventor: Jorma Laapotti
  • Patent number: 4586984
    Abstract: A press section for a running fibrous web, and a method of pressing therein. The press section comprises a first press zone, means for passing the fibrous web in a closed draw to the first press zone, means for changing running direction of the web after the first press zone to substantially reverse the running direction thereof, a second press zone disposed after the means for changing the running direction of the web, and a central roll forming a part of the first and second press zones, with the first and second press zones being disposed substantially opposite one another about the central press roll and constituting means for compensating compression load and weight of the central press roll, and also comprising means for directing the web in a closed draw out of the press section after the second press zone.
    Type: Grant
    Filed: March 21, 1984
    Date of Patent: May 6, 1986
    Assignee: Valmet Oy
    Inventor: Jorma Laapotti
  • Patent number: 4586983
    Abstract: A pressing method and apparatus for dewatering a fibre web, such as a paper or cardboard web, in a paper machine press section including two press rolls through which the web is conducted carried on either a single fabric or interposed between a pair of fabrics. The web is pre-pressed in a pre-pressing zone located in the throat region between the press rolls. The pre-pressing pressure is applied to the web through the mediation of a substantially impermeable band which passes through the press nip in overlying relationship with the web as the latter is conducted over a sector of one of the press rolls. After the pre-pressing step, the web is immediately conducted through the zone of the press nip, the pressing of the web which takes place in the press nip determining the dry matter content of the web subsequent thereto. The pre-pressing zone immediately precedes the zone of the press nip so that the pre-pressing and nip zones together in combination constitute a pressing zone.
    Type: Grant
    Filed: August 8, 1984
    Date of Patent: May 6, 1986
    Assignee: Valmet Oy
    Inventor: Jorma Laapotti
  • Patent number: 4576682
    Abstract: An improvement in a long-nip press for a paper making machine, and a method for applying pressure in the press zone of such a long-nip press. The improvement is directed to providing a press shoe arrangement in the press nip that comprises a frame component, means for articulately engaging the frame component with a stationary structure, a first shoe component disposed in the frame component with means for applying pressure to the same, a second shoe component formed as a part of the frame component itself along with means for applying pressure to the same, with the press shoe arrangement constituting means for incrementally increasing pressure on a press belt and in the press zone itself. The method of the present invention is directed to applying pressure on a running fibrous web through a press nip, by incrementally applying greater and greater pressure onto the running fibrous web as it passes through the press nip.
    Type: Grant
    Filed: March 19, 1984
    Date of Patent: March 18, 1986
    Assignee: Valmet Oy
    Inventor: Jorma Laapotti
  • Patent number: 4568423
    Abstract: Apparatus for the press treatment of a fiber web in a long or extended press zone includes a first press fabric loop in which a press roll is situated and a press shoe situated within a press belt loop which acts in opposition to the press roll, the latter being supported on a transverse beam. The press roll and press shoe together form an extended press zone through which the web to be pressed is guided. The press shoe includes a pressure chamber isolated from the external environment by sealing members and to which a pressure medium, such as a fluid under pressure, is passed. The pressure chamber acts within the extended press zone on the press belt.
    Type: Grant
    Filed: October 13, 1983
    Date of Patent: February 4, 1986
    Assignee: Valmet Oy
    Inventor: Jorma Laapotti
  • Patent number: 4551205
    Abstract: A press section of a paper machine has no suction rollers. The paper web is first conducted through a first two-fabric press nip supported by a first fabric which, in conjunction with a pick-up roller, serves as a pick-up fabric. The press section has press rollers in closed roller combination defining press nips with each other. A first two of the press rollers are provided with solid recessed surfaces. A third of the press rollers is a smooth-surface central roller of the press section. The second fabric serves as a press fabric at least in the first two-fabric press nip. The web is conducted through the first press nip defined by the first and second press rollers interposed between the first and second fabrics. The web is conducted through a second press nip supported by the first or second fabric. The second press nip is defined between the second press roller and the third press roller.
    Type: Grant
    Filed: August 17, 1983
    Date of Patent: November 5, 1985
    Assignee: Valmet Oy
    Inventor: Jorma Laapotti
  • Patent number: 4526655
    Abstract: A press section of a paper machine comprises, in the direction of web run, at least three separate press nips for removing water from a web, the web passing between two fabrics in each of the three nips. Dewatering of the web takes place through both faces of the web at least in the first press nip which is formed between two open-faced press rolls. The second and third press nips are formed between an open-faced roll and one of an open-faced roll and a smooth-faced roll. According to the invention, the press section includes two upper fabrics and two lower fabrics, the first upper and lower fabrics in the direction of web run being water-receiving press fabrics, one of which constitutes a press fabric only in the first press nip, the other fabric constituting a press fabric both in the first and second press nips. One of the second upper and lower fabrics is a water-receiving press fabric, the other being a water-non-receiving transfer fabric adapted to receive minimal amounts of water, if any.
    Type: Grant
    Filed: September 12, 1983
    Date of Patent: July 2, 1985
    Assignee: Valmet Oy
    Inventors: Mikko Karvinen, Jorma Laapotti
  • Patent number: 4525241
    Abstract: A closed press section of a paper machine in which a paper web leaving the wire section of the paper machine is passed, supported by a first upper fabric, through a first double-felted press nip formed by two hollow-faced rolls. The lower fabric in the first double-felted press nip is a second fabric which carries the web forwardly after the first press nip. The press section further includes a smooth-faced central roll against which at least two single-felt nips are formed, the press fabric in the first one of the single-felt nips being constituted by the second fabric. The web is detached from the second fabric and adheres to the face of the smooth-faced central roll and moves along therewith into the next single-felt nip. The press section is devoid of press rolls of the suction type with the first double-felted press nip being formed between two solid-mantle hollow-faced rolls.
    Type: Grant
    Filed: February 28, 1983
    Date of Patent: June 25, 1985
    Assignee: Valmet Oy
    Inventor: Jorma Laapotti