Industrial historical research is always fascinating. Although you know the instrument, it is nice to find the original patent. In this case, this brilliant invention was patented in 1953. There is still a lot of handwriting on the patent, found by Google Scholar, also a fantastic instrument.

The patent explains first which problem is solved with the invention. Indeed, the powdered batch does not sinter homogeneously but in small and large parts, all irregular shaped. After sintering, when the foaming starts and the parts are expanding, it happens easily that two parts touch and are also lifting each other, inducing a fold because everything is confined in a mold. A fold in a glass foam disturbs the cellular structure and so the mechanical stability, reducing largely the productivity.

By using this dicer, regular blocks of powder are formed, which will also sinter in a regular homogeneous shape. During foaming, the sintered blocks touch but lifting is less probable and so the formation of the fold. By working with small blocks, the heat can better penetrate into the little blocks for a more homogeneous sintering and foaming.

By using a dicer, we can expect an improved productivity by less folds and faster sintering. The patent also mentions (column 5, line 31) that the patent is not only valid in a mold but also on a belt conveyor. The dicer could be replaced by rotating devices like for example a series pizza knifes.

This patent is a typical example of very intelligent research: simple with enormous excellent consequences. After so many years (61 years), it is still used by Russians and Chinese cellular glass producers. The picture showed a “diced” block from the STESS factory in Russia.