In order to be able to process workpieces with a robot or handling device, the orderly feeding or removal of these workpieces is one of the most important processes. If the alignment or the position of the workpiece is inaccurate during feeding, this can lead to disruptions in the production process, as the part cannot be gripped correctly or jams in a fixture. When removing delicate or complexly shaped workpieces, they cannot simply be thrown into a box, because this would damage their surface or require enormous effort to reorder them again so that they can be fed in the correct position for the next machining process. The workpieces therefore have to be stored in small boxes so that they can be fed or removed in an orderly manner. These pallets, trays, blisters, cups or small load carriers (KLT) can be easily transported, stacked and reused. They now have to be integrated in an effectively way into a production process without requiring a lot of personnel. The tray changing systems, also called palletizers, solve the feeding and removing of trays in the stack in an economical and reliable way.
The palletizer or depalletizer is a compact tray changing device, which will be load or unload by an industrial robot, fed tray stacks, seperate the trays or tray blisters and restack them. The operating principle of the palletizer allows different pallet flow directions. If the stack of filled trays is heavier than 15 or 25 kg, they may no longer be removed manually. In such a case like this, the basic unit can be extended by a docking station for transport trolleys, for example. It is also possible to transfer the stracks to a ground conveyor with an appropriate device fully automatic. The integration of two tray changing systems is an other opportunity. The exact positioning and quick change of the trays as well as the large storage capacity meet the requirements of an automated production line and automatic palletizing. The typical application of the palletizers or depalletizers can be found in the areas of small parts assembly and the palletizing or depalletizing of parts on plastic injection molding machines and tooling machines.
The Hirata palletizers/depalletizers are available in different versions depending on the task. Simple designs of the tray changers without or with handling unit are for example especially suitable for palletizing tasks, where the workpieces have to be taken out of a tray and put back into the same tray after processing. Both the processed and the unprocessed tray stack are on the lower level. These designs are predestined for use on injection molding machines or tooling machines and their flat design offers good possibilities for an integration into an application with articulated arm or gantry robots. These simple tray changers can also be extended by different modules. Also for fed and removal of trays with low autonomy and for the semi-automated areas, there are correspondingly simpler designs