Roll Spacing Measurement Method
Original Publication Date: 1984-Sep-01
Included in the Prior Art Database: 2005-Feb-05
A direct method for the measurement of small distances between solid surfaces is provided by the apparatus of Fig. 1. As an example of the application, the gap spacing of the magnetic brush roller to the photoconductor drum in an electrostatic printer can be measured. Current methods typically involve use of the shim stock or "feeler gauges" which are inserted into a gap to be measured. A certain degree of operator judgment is required as to the level of force used in the insertion. In addition, measurement resolution and accuracy are limited for several reasons. First, shims or gauges of less than .001 inch are too fragile for practical use. Secondly, to cover a wide range, a large collection of gauges would be required. Finally, stacking of several gauges together produces uncertainty due to contaminated films, etc.