Register control means for web processing apparatus

摘要

A register control for web processing apparatus operates to match the surface speed of a metering roll which supplies a preprinted web to a cutting zone in a cutter mechanism to the surface speed of an impression cylinder which applies impressions and associated register marks to said web. The register control also effects registration between the impressions and the cutting zone. The web processing apparatus comprises a register control motor for the metering roll and a movable dance engageable with the web at a location between the impression cylinder and the said metering roll. The register control comprises base speed selector means and circuits for operating the register control motor to establish and maintain a base speed for the web; error correction sensors and circuits for ascertaining a register error, if any, and for adjusting the base speed to establish a corrected base speed to eliminate the register errror; dancer position locater sensors and circuits for ascertaining and remembering a null position assumed by the dancer when the web is operating at corrected base speed; and for subsequently recalling the null position to enable an initial or start-up operation of the register control motor at a speed wherein the dancer assumes the recalled null position when the web is engaged with the dancer.