Druckerantriebswalze mit sandgestrahlter Oberfläche, und Lagermontagemethode

摘要

A drive roller for an ink-jet printer. The drive roller has a media engaging surface that is roughened by grit blasting along an entire media engaging longitudinal peripheral extent. The surface is hardened by anodizing. The roller is relatively inexpensive to fabricate yet has a small error on diameter and run out, and high traction due to the surface roughness, to provide highly accurate media positioning performance. The drive roller rotates about shaft mounted bearings. The shaft journal is formed with a small raised bump, which has very loose diametrical tolerance requirements, but is short in comparison to the bearing length dimension. When the bearing is press fit onto the shaft journal, the material forming the raised bump is sheared by the bearing. The sheared material drops into a recess on the journal, and does not interfere with the axial positioning of the bearing. The axial position of the bearing is controlled by placing the bearing next to a shoulder formed on the shaft.