Visual indicator for alternate units of measure

摘要

A mechanical device alternately visually displays measurements, such as measurements of distance, in either one of two different units of measure. The apparatus comprises a dimensionless rotary indicator means carried by a frame to be visually observable by a user. The indicator means has rotatable input means and is calibrated in units and selected fractions thereof. Motion amplifying gear means are carried by the frame and are continuously coupled to the indicator means. The gear means operate the indicator input means faithfully in response to rotation of a rotary input shaft to the apparatus. The gear means include alternate input gears which are alternately engageable in a more directly driven relation with the input shaft than the other. The apparatus also includes selectively operable mode selector means, operable for engaging one or the other of the alternate input gears in said more directly driven relation. The gear ratios between the input gears and the indicator input means are different by an amount corresponding to the conversion factor between the two different units of measure which preferably are inches and centimeters.