Original Publication Date: 1977-Jun-30
Included in the Prior Art Database: 2004-Mar-30
Xerox Disclosure Journal
A scanning polygon assembly is provided which comprises a plurality of identical facet blocks 10 arranged for 3600 in abutting relationship on a platform 25. The platform 25 has an annular lip 36 against which two corners of each block abut so the facets 12 form chords along the lip to form a polygon. The abutting relationship between the blocks is a tight fit but not a forced fit in order that the blocks are free enough to allow the corners 40 and 42 of each block to engage the lip 36 (and thus assure such engagement) due to the centrifugal force exerted thereon during rotation of the polygon. An annular shallow groove 43 is located in the surface of plat-form 25 across which the facet blocks 10 span. The width of the groove is substantial compared to the distance between edge 16 and facet 12 (approximately 80%) . The purpose of the groove is to decrease the area of surface on which the blocks 10 rest to substantially reduce the effects of an imperfect surface 25 on the blocks 10, which may tend to tilt each block and increase the angle tolerances between the facets 12.