Rotary operated character selection system for postage meters

An improved postage meter having a rotatable print drum in driven communication with a drive motor assembly, said print drum housing a plurality of print wheel assemblies each print wheel assembly having at least one print wheel having an outside generally cylindrical surface with a plurality of characters in discreet positions on said outside surface, each of said print wheel assemblies having a print wheel gear for selectively positioning said respective print wheel assemblies, so that a selected one of said plurality of characters may be moved to a printing position, a print wheel adjustment assembly for sequentially communicating with said print wheel assemblies, said improvement comprises:

• said print wheel adjustment assembly being mounted in said postage meter in fixed location relative to said print drum;
• said print drum being rotatable to a plurality of print wheel assembly adjustment positions, each of said adjustment positions bring a respective one of said print wheel gears into engaging contact with said print wheel adjustment assembly;
• control means in communication with said drive motor assembly for selectively causing said drive motor assembly to rotate said print wheel assemblies carried by said print drum through said printing position in a printing cycle or to rotatably displace said print drum to any one of said plurality of adjustment positions;
• and,
• indexing means for informing said control means when said drive motor assembly has caused said print drum to assume one of said adjustment positions, said indexing means including:
• a gear member rotatably mounted in said postage meter and in driven communication with said drive motor assembly such that displacement of said print drum by said drive motor assembly causes a corresponding displacement of said gear member;
• a plurality of encoder means fixably mounted to said gear member such that a respective one of said encoder means is placed in communication with a decoder means when said gear member is placed in a position corresponding to a respective one of said adjustment positions of said print drum;
• and
• a decoder means fixably mounted in said postage meter for cooperating with said encoder means and producing electrical signals indicative of the location of said print drum in a particular one of said adjustment positions and communicating the position of said print drum to said control means.