Perspective drawing device and combination of perspective and parallel drawing device

Claim 1

A DRAWING DEVICE AT LEAST FOR PERSPECTIVE DRAWING COMPRISING BASE MEANS, A SINGLE PIVOTAL ARM, ARM PIVOT MEANS HAVING A VERTICAL AXIS AND PIVOTALLY MOUNTING THE ARM ON THE BASE MEANS, A LEVER, LEVER PIVOT MEANS HAVING A VERTICAL AXIS AND PIVOTALLY MOUNTING THE LEVER ON THE ARM AT A POINT SPACED FROM THE ARM PIVOT MEANS, AN OPERATING CONNECTION BETWEEN THE BASE MEANS AND THE LEVER TO MAINTAIN THE LATTER IN THE SAME RELATIVE ANGULAR POSITION WITH RESPECT TO THE BASE MEANS THROUGHOUT THE PIVOTAL MOVEMENT OF THE ARM INCLUDING A FIRST FIXED MEMBER SECURED TO THE LEVER AND A SECOND FIXED MEMBER SECURED TO THE BASE MEANS, AND A CONNECTING LINKAGE BETWEEN THE FIXED MEMBERS; RULING EDGE MEANS INCLUDING A RULING EDGE MEMBER HAVING A RULING EDGE, RULING EDGE, PIVOT MEANS PIVOTALLY MOUNTING THE RULING EDGE, MEANS ON THE LEVER AT A POINT SPACED FROM THE LEVER PIVOT MEANS AND HAVING A VERTICAL AXIS, AND THE RULING EDGE MEANS ON THE MENT WITH THE AXIS OF THE RULING EDGE PIVOT MEANS; AND CONTROL PIVOT MEANS HAVING A VERTICAL AXIS AND CARRIED BY THE ARM, THE CONTROL PIVOT MEANS INCLUDING A CONTROL PIVOT HAVING ITS AXIS ON A LINE EXTENDING FROM THE AXIS OF THE LEVER PIVOT MEANS AND VERTICAL TO A LINE BETWEEN THE AXES OF THE ARM PIVOT MEANS AND THE LEVER PIVOT MEANS, SLIDE MEANS CARRIED BY THE CONTROL PIVOT HAVING ITS AXIS AT RIGHT ANGLES TO THE AXIS OF THE CONTROL PIVOT, AND CONTROL ROD MEANS SECURED TO THE RULING EDGE MEANS AND EXTENDING AT RIGHT ANGLES TO THE RULING EDGE AND SLIDABLY RECEIVED BY THE SLIDE MEANS CARRIED BY THE CONTROL PIVOT MEANS.