Graphic data system for scanning and recording two-dimensional contours

Claim 1

A contour data recording system comprising a draft plate supporting table, a coordinate ''''X'''' axis and ''''Y'''' axis carrier assembly comprising a carriage beam extending over the plane of said table in close proximity thereto and in parallel disposition therewith, said beam being situated with its principal geometric axis in the direction of the coordinate ''''Y'''' axis, a cross member supporting one end of said beam, said cross member being movably mounted on said cable on one margin thereof, the direction of motion of said cross member being parallel to the ''''X'''' axis direction, an electrical impulse generator carried by said beam and drivably coupled thereto whereby it is adapted to generate an electrical impulse voltage for each incremental movement thereof in a ''''Y'''' axis direction, a carrier movably mounted on said beam and supporting said impulse generator, an optical scanner carried by said carrier, a second impulse voltage generator carried by said cross member, said second impulse generator being coupled drivably to said table where it is adapted to generate a voltage impulse for each incremental movement of said beam in an ''''X'''' axis direction, two driving and two driven electrical units, one of said driven electrical units being connected to said cross member and the other being connected to said carrier, operator-controlled drive means for driving said driving electrical units whereby manual ''''Y'''' axis adjustments and manual ''''X'''' axis adjustments of said scanner can be accomplished, the drive means for driving said driving electrical units comprising both a coarse adjustment hand element and a fine adjustment hand element adapted to be connected drivably to said driving electrical units, said drive means including speed reducing torque transmission elements between one of said fine adjustment hand elements and its associated driving electrical unit to permit increased sensitivity in the adjustment of said scanner in the ''''Y'''' axis direction, said cross member comprising a pair of rollers spaced at a substantial span in the ''''X'''' axis direction, a rail mounted on one side of said table, said rollers engaging said rail and movable therealong during ''''X'''' axis adjustments and means for supporting the opposite end of said beam comprising a relatively friction free bearing between said beam and said table, the bearing at said opposite end of said beam comprising an air pressure manifold carried by said beam, an air bearing surface carried by said table, said manifold having a flat surface situated in juxtaposed relationship with respect to said table bearing surface, at least one air jet extending through said manifold surface and means for supplying pressurized air to said jet whereby a relatively friction-free air cushion is established between said manifold and said table bearing surface.