The in-house movement of materials can be unproductive and costly, tying up employee time and warehouse space. However, by optimizing batch sizes, packaging plants have the potential to save considerable amounts of money each year. To do this, companies need to control the logistical and organizational processes within their operations.

While automated conveyor systems are still largely unknown among sheetfed offset printers, a few have developed fully automated production processes that allow them to concentrate on monitoring, control and maintenance functions. The Heidelberg Logistics system is part of a modular automation concept that encompasses the various requirements of the printing press. The Logistics system integrates the various requirements of a press to increase production through nonstop, automatic operation. It reportedly provides precise positioning, reduces waste and removes physically strenuous work.

The system is comprised of three components: Autopile, a roller conveyor system; Nonstop, the automatic pile change unit; and AGV, an automatically guided vehicle. Each of these modular components can be combined, upgraded and retrofitted, depending on the specific production structure, materials used and growth within a company.

An important function of the Autopile component is the distinction made between pallet transport and pallet utilization by the printing press. This is done by buffering the individual conveyors. Full pallets, pallets in use and empty pallets are handled independently of one another at both the feeder and delivery.

The pallets only travel in one direction, minimizing pile-changing times. Pallets with stock enter on the drive side, and pallets without stock emerge on the operator side. Empty pallets travel either automatically or manually between the feeder and delivery depending on the selected configuration.

Nonstop, the system's automatic pile changer, is said to allow operators to quickly and safely change pallets at the feeder without interrupting press operation. The fully automated pile changer rests above the feeder until it is time to change the pile. The unit then reportedly matches the height of the pallet and takes over the auxiliary pile while a fresh pallet is being loaded. After the main and auxiliary piles have been precisely rejoined, the pile changer returns to its resting position. The operator can still change piles manually if required.

At the delivery, the transport is prepared by inserting a rake manually. The pile pallet is then lowered and the delivery conveyor transports the pile to the drive side where it is ready for takeover. An empty pallet is then placed into the delivery from the operator side.

The automatically guided vehicle, or AGV, is designed for automated in-plant transfer of pallets between storeroom, pile turner, printing presses and finishing sections. Installing a driverless transport system calls for well-organized, orderly work routines and carefully defined travel routes. Reportedly, it is most economical when large quantities of materials need to be handled.

The system's AGV has a 100-mm-high, integrated roller-conveyor track that allows it to dock up against the Autopile system. A four-wheel steering design gives it the mobility for use in printshops where space is at a minimum. The vehicle's guidance system was developed for shopfloor applications and does not use wires embedded in the floor, which avoids damaging the ground structure.

The frame of the AGV is shaped to permit safe and reliable transport of full pallets. Even in the event of a sudden stop, the piles cannot slip or topple, regardless of the size of the pallet or pile. The vehicle travels at right angles to the roller conveyor, which allows a press on either side to be serviced as soon as possible from a single, central supply path.