Drawing block for blind persons - is made from elastic material and has auxiliary plate under top plate with pattern in relief and leaves traces from pointer

摘要

The drawing block, for blind people, consists of a plate made from an elastic material. It is covered by a plastic sheet, which leaves a trace that can be felt when acted on by a pointed object. The plate has a profiled surface. There is an auxiliary plate under the first plate. The bottom plate has a pattern in relief. The block (1) can be square or rectangular with raised edges (12). There are cutouts at regular intervals along one of the edges, and it can therefore be used as a ruler, which has a continuous slot (4) along its entire length. This slot will engage a T-square (5) so that it will lie horizontally and move vertically.