In accordance with the principle that nothing is so good that it cannot be improved, a manufacturer of furniture, office furniture, trade-fair stands and fittings for caravans and mobile homes in South Germany, Vöhringer GmbH in D-72818 Trochtelfingen, recently purchased a dual woodworking centre from Homag. The objective of this was to minimise the non-productive idle times of the machine by using the two ends of the large machine table alternately. Since this large table makes it possible to remove the finished parts and load new raw materials at the one end while the parts are being machined at the other end, the machine is practically never idle and the machine running times are fully utilised production times. So far so good, but not enough for Theodor Schwenk, factory manager at Vöhringer GmbH, since at least two persons had to be available whenever the finished parts were removed and the new sheets of wood placed on the machine, something which cost time and money. Since Theodor Schwenk had already experienced good results with a vacuum handling system in a different production area, he thought that equipping the new dual machining centre with a further vacuum handling system would improve the efficiency even further.

Handling of large sheets of wood and MDF

No sooner said than done: in close cooperation with the persons working at the machining centre and with the handling and material-flow engineers of the vacuum specialist J. Schmalz GmbH in D-72293 Glatten, a convincing solution for the handling of laminated sheets of wood and sheets of MDF was quickly created. These sheets have dimensions of up to 3,200 x 1,400 mm, are up to 28 mm thick and weigh up to 60 kg: They are now moved and positioned with the aid of a vacuum tube lifter of the type JumboErgo 140. The vacuum tube lifter is equipped with two suction pads which can be positioned anywhere on a longitudinal beam, making it easy to balance the load and to adapt the gripper to the varying dimensions of the sheets. The necessary vacuum is generated by a powerful, directly driven vacuum blower of the type SBL with a dust filter to keep out wood chips and sawdust. A storage net is mounted on the lifting tube for space-saving storage of the device when it is not in use thus preventing damage to the gripping system. A special feature which deserves mention is the extra-long operator handle. Since the dual machining centre has a large (double) table, and because even the largest sheets of wood have to be moved safely and quickly and positioned precisely, the long operator handle permits ergonomic handling while allowing the operator to keep well away from the suspended loads.

Handling systems as complete solutions

However, the handling system for the dual woodworking centre consists of more than just the vacuum tube lifter: it also has an aluminium single-beam crane system to permit traversing of the vacuum tube lifter over the entire working area. Due to the size of the machine table, the area for storing pallets with fresh sheets of wood and MDF, the area for storing the finished parts, and the size of the raw sheets, this working area has the dimensions 7,000 x 5,000 mm. The single-beam crane system is constructed from aluminium sections and mounted on the ceiling to save space. It carries the vacuum tube lifter, which can be moved to any desired position within the working area. The lightweight crane system is designed for loads of up to 140 kg and its trolleys can be moved easily, even with the full load suspended. Schmalz supplied the complete handling system, which means that Vöhringer has only one contact partner. Factory manager Theodor Schwenk is very satisfied with this Schmalz handling system. Today, only one person is needed for handling of the raw sheets and finished parts, and still has time to control and monitor the operation of the machine. In the past, two persons were needed for loading and unloading the machine and one of these also had to operate the machine. The vacuum handling system also moves the sheets and finished parts more safely and with less damage, and thus makes the production of wooden and MDF parts even more economic.