Tolerance field demonstration sheet for teaching purposes - has set of vertical columns pierced with two sets of holes to show compatible sizes

摘要

The tolerance field sheet is used for demonstrating fitting tolerances for shafts or rods inserted into holes or bearings. The sizes of the holes and bearings cover a wide range and large shafts must be matched up with large bearings and vice versa. The sheets have vertical columns which correspond to the mutually compatible sizes of the shafts and bearings and these columns are designated by upper case letters at the top for the bearing and lower case letters at the bottom for the shaft. Different coloured lamps shine through holes designating the tolerance ranges of the shaft and bearing, and there is a vertical distance scale calibrated in um. The sheet is used for instructional purposes. The two sets of holes are arranged into crossings shapes.