Patent ID: 6273243
Filing Date: 2001-08-14
Classification: F16H

Abstract:
A device for correcting the run of a belt for a letter sorting and distribution system, comprising:a rotatable adjusting roller which contacts the belt, so that the belt runs on the roller in a running direction with an angle of wrap and having a tangential direction, the belt presenting a belt force against the adjusting roller;a lever arm for supporting the adjusting roller, the lever arm being pivotable around a pivot axis so that the belt force provides a belt torque around the pivot axis, and the lever arm having a longitudinal axis perpendicular to the pivot axis and defining an angle of inclination between the longitudinal axis of the lever arm and the tangential direction of the belt; anda spring element having a spring constant and attached to the lever arm at a first mounting location at a distance from the pivot axis, for applying a spring force to the lever arm to generate a spring torque around the pivot axis,wherein the angle of wrap, the running direction, the tangential direction, the angle of inclination, the spring constant, and the first mounting location are provided so that the spring torque has a stable torque equilibrium with the belt torque when the belt force is centered on the adjusting roller, andwherein occurrence of an off-center deflection of the running of the belt on the adjusting roller causes tilting of the adjusting roller due to change in the torque equilibrium between the spring torque and t he belt torque on the adjusting roller, wherein the tilting of the roller moves the belt on the adjusting roller with a correction component in a direction opposite to the direction of the off-center deflection to correct centering of the belt.