Patents by Inventor Heikki Ilvesppaa

Heikki Ilvesppaa 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: 5135614
    Abstract: The invention concerns a suction roll (10) for a paper making machine, on which the paper web is pressed towards the outer face of the roll mantle. The suction roll (10) is divided, in the axial direction of the roll, into at least three vacuum spaced (A.sub.1, A.sub.2, A.sub.3). In the interior of the suction roll (10), there are at least two partition walls (17a, 17b), by means of which the suction space (13) is divided into separate zones of negative pressure. The lateral vacuum spaces (A.sub.1, A.sub.3) in the suction space can be subjected to a higher negative pressure than the vacuum space (a.sub.2) in the middle area of the roll, whereby the profile of negative pressure is formed such that the negative pressure increases across the width of the roll towards the lateral areas. The invention also concerns a method for producing a desired pressure profile for a suction roll.
    Type: Grant
    Filed: December 5, 1990
    Date of Patent: August 4, 1992
    Assignee: Valmet Paper Machinery Inc.
    Inventors: Jouko Aula, Heikki Ilvesppaa, Allan Liedes