Abstract: A digital scaler for measuring and displaying a distance on a drawing surface comprising a first triangle with a verticle straight edge and a second triangle with a horizontal straight edge slightably engaged with the first triangle along the vertical straight edge. A drive in the form of a drive wheel and pulleys are connected between the first and second triangles and can be activated to displace the second triangle with its horizontal straight edge along the vertical straight edge of the first triangle. A horizontal displacement measuring device is connected to the first triangle and engageable with the drawing surface to measure the linear displacement of the first triangle when it is drawn horizontally across the drawing surface. A vertical displacement measuring device is connected to the drive wheel and measures the displacement of the second triangle along the vertical straight edge of the first triangle when the drive wheel is rotated.

Abstract: A digital drafting machine for measuring and displaying a distance on a drafting surface comprising a first triangle with a vertical straight edge and a second triangle with a horizontal straight edge slidably engaged with the first triangle along the vertical straight edge. A drive in the form of a drive wheel and pulleys with a cable rapped therearound disposed in the first triangle with the cable connected to the second triangle, the drive wheel being rotatable to displace the second triangle with its horizontal straight edge along the vertical straight edge of the first triangle. An optical horizontal displacement measuring device is connected to the first triangle and includes a light sensor for sensing the passing of the drawing surface to measure the linear displacement of the first triangle when it is drawn horizontally across the drawing surface.

Abstract: A universal drafting triangle comprising a lower or first triangle laminate having a surface groove spaced from and along its three sides with rollers adjacent to angles of the triangle and connecting with the groove and a drive wheel adjacent to the remaining angle of the triangle and connecting with the groove. A belt drive such as an "O" ring is disposed within the groove and wrapped around the rollers and wheel. A raised track is disposed on the triangle laminate adjacent to one side of the triangle and spaced from the groove along that side. A slide member is adapted for sliding along the track and has an indentation for entrapping a portion of the "O" ring riding inside the groove adjacent to the track. The sliding member is in turn connected to a second solid triangle which is adapted for sliding along the adjacent side of the triangle laminate. The two rollers and wheel are disposed in indentations communicating with the grooves.