Abstract
Belt loops supported by rollers commonly appear in xerographic type copying machines. Recently, rollers have been designed with special mechanical features employing a series of stacked annular discs mounted on a solid drive shaft. This configuration reduces the transverse forces acting on the belt due to edge guidance, and provides a method of belt control which eliminates the need for costly active belt steering servo systems. Rollers of this type are referred to as low lateral force (LLF) rollers. The addition of these lateral load inhibiting features necessitates that the rollers be carefully scrutinized for buckling and deformation, thereby ensuring accurate belt control for high quality xerographic copying.
A parameterized finite element model of a LLF roll has been developed. The results acquired from the model are presented in dimensionless form in terms of the physical variables that describe the geometric parameters of the discs comprising the roller: thickness, inner and outer radii and belt contact angle. Dimensionless forms for the buckling belt tension and the circumferential and axial stiffnesses of the discs are also evaluated and displayed against the dimensionless geometric parameters, using contour plots for belt contact angles of 45°, 90°, 135° and 180°. These plots have been employed in practical design calculations for the sizing of LLF rolls.
