Rolling system to raise curtains, stairs and others. (Machine-translation by Google Translate, not legally binding)

摘要

Improvements introduced in the object of the main patent no. 444431 by system of treads to climb curbs, stairs and others, and is characterized by being formed by a triangular plate with an axis at its center, and at the ends of the vertices are coupled three (3) wheels that rotate around an axis. (Machine-translation by Google Translate, not legally binding)