BELT DRIVE MULTI RATE SCAN SYSTEM
Original Publication Date: 1983-Aug-31
Included in the Prior Art Database: 2004-Apr-04
Xerox Disclosure Journal
In some automatic reproducing machines it is desired to have a scanning system which is capable of driving a scanning system at a plurality of scanning rates. The figure illustrates a relatively simple compact system using timing belts and pulleys instead of a complex network of gears, racks and cables. In the figure full rate scanning as well as 3/4, 1/2 and 1/4 rate scans may be achieved. The rotation of the input pulley 10 having twelve teeth provides the full rate belt A with a velocity F. This velocity F may be cut in half by the 24 to 12 ratio of teeth on cluster pulley 12 such that the half rate belt C now moves at velocity F/2. This half rate velocity may be halved once again by a similar 24 to 12 ratio of teeth on cluster pulley 14 to provide the quarter rate belt D a velocity of F/4. The half rate velocity may be stepped up by the 12 to 18 ratio of teeth of cluster pulley 16 to input a velocity of 3/4 F to the 3/4 quarter rate belt B. This provides a final result of full rate, half rate, 3/4 rate and quarter rate velocities for the scanning system. The pulleys 18 are all twelve tooth idler pulleys and the pulley 20 is smooth surfaced. While this concept has been illustrated with four pulley clusters any combination of ratios may be employed.