Patent ID: 7793775

Claim:
An apparatus comprising: a mailpiece inserter configured to transport envelopes to an insertion area, receive mailpiece inserts into the envelopes at the insertion area, and transport the envelopes with inserts to another area; a gripper chain for transporting the envelopes, the gripper chain comprising a continuous chain and grippers on the continuous chain for receiving the envelopes; a transmission system for supporting and rotating the gripper chain in a loop, wherein the gripper chain comprises a vertically sagging generally arcuate section on the transmission system, and wherein the transmission system comprises a chain tensioning device; a sensing system comprising: a first sensor for sensing a first one of the grippers at a first location; and a second sensor for sensing a second one of the grippers in the vertically sagging generally arcuate section of the gripper chain at a second location, wherein the second sensor is configured to sense presence of the second gripper at the second location when the vertically sagging generally arcuate section of the gripper chain droops a predetermined amount due to wear in the gripper chain and to send a signal responsive to sensing the presence of the second gripper; and a controller configured to receive the signal from the second gripper and, responsive to the signal, to control the chain tensioning device to reduce the amount of droop of the gripper chain and to adjust a position of the gripper chain and the transmission system with respect to the insertion area.