GETRAG Getriebe- und Zahnradfabrik
When, in light of the order from Audi for the manufacture of its six-gear transmission, Getrag built a new workshop with a dispatch warehouse attached, H+H Herrmann + Hieber was awarded the contract for the automation concept.
H+H Herrmann + Hieber recommended a system with an automatic crane and a block store. The advantages of such a system compared with a floor conveyor technique ( which Getrag had already been considering at the time) include lower costs, a higher quality level due to automated sequences, greater flexibility, and smaller space occupancy. The concept was persuasive. Among other things, Getrag could save at least three-quarters of the floor-space and in terms of time-saving as well, the automatic crane has proved to be substantially better.
For storage and transport Getrag uses two Audi rack types, each designed for a maximum of five six-gear transmissions. The unladen weight of the racks is 70 kilograms and when full they weigh 480 kilograms.
The racks are transported by a chain conveyor from the production area for transfer into the dispatch warehouse. Before a command is issued to the automatic crane, the rack goes through a height and footprint check.
If a rack has passed these checks, the warehouse management computer generates a transport command and transmits it to the crane controls. The automatic crane, with a span width of around ten metres, performs 30 working cycles per hour. The load uptake gripper system has been specially adapted for the racks and the restricted space in the warehouse.
The racks, owned by Audi, are returned by truck after delivery. For the transport into the dispatch warehouse chain conveyors have been installed. The driver of the stacking machine forms stacks of five empty racks at a time on the conveyor. These go through a height check in which they are checked for obliqueness by a horizontal light screen at the height of the topmost rack. That is necessary because of the small tolerances in the dispatch warehouse. At the end of the chain conveyor stretch the stack of racks is transferred to the automatic crane, which then transports them individually.
Since the loading area is within the action range of the automatic crane numerous safety circuits have been created, which ensure that people can enter the area safely.
The great advantages of the crane solution are cost saving and flexibility. The crane takes over all the jobs to be done: return of the empty racks, transfer into and recovery from store, preparation for dispatch and the separation out of damaged racks. It also keeps on working during supposed rest periods when no order actually has to be prepared , and in the third shift. At those times it condenses the stock and assembles loads for future orders.