Patents by Inventor Pertti J. Helander

Pertti J. Helander 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).

  • Openable closing device for freight or storage tanks
    Patent number: 4460110
    Abstract: So that a freight or storage tank for bulk material, that has at least one long emptying hole on the bottom, can be closed and opened, the tank has at least one flexible belt that extends essentially over the length of the opening and whose one end is attached to the tank, and under which is a roller or roller system that is approximately of the same length and that supports the belt when in the closed position and that can be removed from the closed position, as well as elements to move the roller or roller system across the opening between two extreme positions.
    Type: Grant
    Filed: March 9, 1982
    Date of Patent: July 17, 1984
    Assignee: Esko Pollto Oy
    Inventor: Pertti J. Helander