Flexible product demands flexible handling

Designing a handling and assembly plant for 3m long washing machine hosing that remains flexible right up the packaging station presents obvious problems. A good deal of ingenuity therefore needed to be employed by the system designer and builder Heller Automation. To provide the necessary operational flexibility needed by this application, Heller put a HepcoMotion DTS linear track system at the heart of the assembly.

The resultant plant occupies an area of 100m2 and comprises several sections. After being fed into the system and cut to the required length, the hose is sorted into two sizes and transported to an assembly station to be fitted with a threaded tube connector. It then travels into one of four press stations and eight pressure testing stations and finally into packing.

With a profile width of 44mm and 612mm diameter segments, the overall feed length of the Hepco DTS Driven Track System employed is 21m. It is equipped with a total of 36 fixed centre carriages, each having two hose-gripper devices. The carriages are usually positioned at equal pitches along the track. However, as the need arises they can be re-set at irregular intervals to ensure the precise control of the hose feed. In this way accurate alignment is assured and deflection from external loads resisted.

Using the HepcoMotion PRT Ring Slides and Track System as its basis, DTS is a complete unit ready to be incorporated into any continuously positioning or dedicated assembly machine. Carriages are propelled around the oval or rectangular circuit with a virtually unlimited straight length. In common with all DTS options, the oval track selected by Heller has an integral belt drive.

Several factors made this system the ideal choice for Heller Automation. The provision of all transmission and mounting components as a complete integrated package afforded significant savings in both design and build time. Also the system is conceived to ensure there are no protrusions above the level of the carriage mounting surface. This enables measuring systems and assembly devices to be attached to the carriages, such as the special grippers employed by Heller.

Another important design attribute of DTS for Heller is its clever trip-latch mechanism that disengages the drive if the movement of carriage is impeded. In the event of a machine malfunction or component jam, the sprung latches which carry the drive from the belt profiles to the carriages, trip out of engagement. This occurs at a resistance of 60N. The latches remain clear of the belt profile until manually reset.

Roland Gross, Managing Director of Heller Automation concluded, “Our customers expect bespoke systems to be completed in short timescales and, of course, at the lowest possible cost.” For this hose handling application HepcoMotion DTS provided an off-the-shelf solution enabling Heller to contain costs through labour savings.