Patents Assigned to Keller Holding AG
  • Patent number: 4604255
    Abstract: With the fabrication method and apparatus for the performance of such method, a blank containing hollow spaces extending between its lower side and its upper side is arranged in a mold closed at least at five sides and expanded. The blank is arranged in a mold box, whose area in plan view is larger than the plan view area of the blank. The space between the blank and the mold box wall and possibly hollow spaces which are retained in the blank are filled with a granular filler material, for instance sand, which is trickleable at least during the mold release of the expanded blank. In this way there is ensured for a simple and positive mold release and a protection of the mold box. The molded body can have different constructions and serve the most different purposes. The molded body is preferably constructed as a lightweight structural element for construction purposes.
    Type: Grant
    Filed: June 16, 1983
    Date of Patent: August 5, 1986
    Assignee: Keller Holding AG
    Inventors: Hans Walt, Dieter Sutterlin
  • Patent number: 4493805
    Abstract: The method of moldless manufacturing light construction elements comprises a first step of mold-free shaping a blank comprising a first layer of an expandable first clay material and a second layer of a non-expandable second clay material. The blanks are supported at their second layers and conveyed through an oven with radiation heating of the blanks at least from above, so that the first layer progressively expands as the blanks are conveyed through the oven. After cooling, the expanded blank is further processed to assume the required final dimensions.
    Type: Grant
    Filed: December 20, 1982
    Date of Patent: January 15, 1985
    Assignees: Keller Holding AG, Gustav-Adolf Sporkenbach
    Inventors: Gustav-Adolf Sporkenbach, Dieter Suetterlin