Servodrive apparatus for driving the postage printing drum in a postage meter

摘要

A servodrive apparatus is disclosed for a postage meter having a postage printing drum mounted for rotation from and to a home position in single revolution increments and a conveyor for transporting individual pieces of mail into operative engagement with the incrementally rotating drum to be printed with postage. The servodrive apparatus drives the printing drum and controls the angular velocity of the drum to be substantially equal to a preselected angular velocity so that noise generated by the meter is decreased and its operating life is increased. This servodrive apparatus includes a motor for driving the printing drum and means for sensing the angular displacement of the printing drum. A signal generator produces a signal proportional to the preselected angular velocity and a comparator compares the sensed angular velocity of the drum and the preselected angular velocity. A motor control responds to the comparator to operate the motor so that it drives the printing drum substantially at the preselected velocity.