Larger parts on the same press: this is the benefit offered by an innovative transfer system to be unveiled by press manufacturer Schuler at the EuroBLECH fair in Hanover, Germany, from October 23 to 27, 2012. Called the Intra Trans, it conveys parts along the x-axis – i.e. the feed direction – by means of movable carriages, whose servo drives are integrated into the transfer rails. The parts are handled by grippers mounted on the carriages.
The distance between stations is generally dictated by the space requirements of the largest forming stage. “As each carriage can be moved individually, this even allows varying distances between stations,” explains Rolf Cisar, Head of Transfer Systems at Schuler Automation in Hessdorf. “This means that the number of stations can be increased or even a smaller press can be used.” The new transfer also means material can be fed from both sides, thus enabling for example the central joining of parts: “It opens up the possibility for completely new manufacturing processes,” says Rolf Cisar.
Thanks to the innovative drive solution, the transfer rails no longer work through the press window – as in conventional solutions – but between the press uprights in the feed direction. This means that the full width of the window is available for material feeding and is no longer restricted by the transfer rails. A major benefit of the Intra Trans’ compact design is that larger parts can be produced on the same press – a key argument when purchasing or modernizing a press line. “Due to its space-saving design and the often restricted die space of existing press lines, the Intra Trans is ideally suited for retrofits,” adds Sales Manager Sven Vosse. “Schuler can provide customers with advice and active support in such matters.”
“We are currently observing a trend away from progressive die and toward transfer technology,” reports Rolf Cisar. In contrast to conventional transfer systems, progressive die technology offers the possibility to use the complete width of the press window for material feeding. The downside is that it involves more scrap as parts are transported from station to station by the coil material itself. This means that additional material has to be subsequently removed from the finished part as scrap. In view of rising metal prices and the growing use of expensive high-strength steels, efficient coil processing is becoming increasingly important.
In the past, however, changing from progressive die to transfer technology generally meant that users could only produce much smaller parts – as the rails of conventional transfers work through the press side window – or that production had to be moved to a new, larger press which offered enough space for the transfer but at the same time incurred higher purchase and manufacturing costs. “The compact design of the new Intra Trans now makes changing to transfer technology much easier,” explains Rolf Cisar.
For the operator, the die can be accessed just as easily as with conventional transfer solutions. During die changes, the transfer rails are placed as usual on brackets and moved out of the press together with the die on a moving bolster or die change plate.
“Despite its compact design, the performance of the Intra Trans is at least as high as that of our other modular transfer solutions,” stresses Rolf Cisar. As with the other models, the new transfer solution features an active vibration dampening (AVD) system which guarantees exact and controlled part transport. Tried and trusted transfer drive housings for tri-axis transfers are used for moving the transfer rails along the y and z axes – i.e. for the opening and closing or lifting and lowering movements. The housings are floor-mounted on the inner side of the press uprights, for example, and also allow asynchronous opening and closing of the transfer rails, i.e. at different times.