Patents Assigned to Harm Willem Holman
  • Patent number: 5487620
    Abstract: Pavement element such as a tile with an upper porous layer (2), below that a liquid-tight layer (3) and possibly there below a heavy layer (4). In order to keep a floor laid with suchlike elements well liquid-tight at the level of the liquid-tight layers sealing means (6) are provided between this layer (3) or one element and the same layer (3') of an adjacent element. Preferably these means consist in a rib or protrusion, which may cover the complete height of the liquid-tight layer. Preferably the porous layer is formed from particles of the same size having an irregular shape and the liquid-tight layer from particle from different particle sizes, such that the particles attain a high filling degree.
    Type: Grant
    Filed: June 28, 1994
    Date of Patent: January 30, 1996
    Assignees: Terra IJssel B.V., Harm Willem Holman
    Inventor: Harm W. Holman