| 摘要 |
A process is disclosed for a perforated rack that is thin, normally curved in cross section, rigidly straight but coilable, and containing perforations adjacent at least one of its longitudinal sides. A new system for the interconversions of linear and rotary motions is then made possible with the perforated rack and a sprocket wheel coupling, and this new system is used for digitizing linear and also polar measurements. When the rack is radially bent toward its normally convex surface, and rotated upon the sprocket wheel coupling aligned with sprockets, the perforations of the rack fall upon and ring fit the sprockets. The sprocket wheel coupling is connected with a shaft position encoder, whereby, the rack motions and encoder signals are proportional relative to linear measurements made finite over relatively long distances of many feet. The rack is also made rotational about a vertical axis connected with a second shaft position encoder having its signals proportional with rotational motions. The linear and angular (rotational) measurements then producing polar coordinates proportional with the positions of a cursor tip attached at the distal end of the rack. The polar coordinates, also made finite, are possible over large surfaces such as standard drafting or working tables. |
