| abstract |
A reversible bidirectionally operable position indicator, driven by a lead screw, for example, is provided for showing the accumulated displacement of a workpiece to either side of a reference point. A coarse reading of displacement is furnished by a resettable counter driven in a selected direction by a transmission coupled to the lead screw and having a bidirectional output. A fine reading of displacement is provided by a manually adjustable vernier scale cooperating with a reference scale driven by the lead screw. A gearing arrangement may be utilized for obtaining indicator readings, selectively, in either the English or metric system. |