Hygienic linear bearings for innovative vegetable packers

• What was needed: drylin SLW linear modules, with drylin plain bearing foil and flex shaft, drylin R shaft guide
• Requirements: For the numerous format adjustments, simple automated systems were needed that work without lubricants and are as maintenance-free as possible.
• Industry: Packaging technology
• Success for the customer: The drylin linear axis and shaft guide solutions enable lubricant-free operation of the system. They contribute to the compact and slim design of the machine. The system fulfils all requirements to the satisfaction of the decision-makers and machine operators.

In the future, Reichenau-Gemüse, a producer organisation, will pack its tomatoes and apples in cardboard trays without any film and thus without any plastic. An S-shaped viewing slit allows a clear view of the product (see Fig. 2 below).
This innovation is made possible by the development work of Dipl.-Ing .Michael Baur. His company is active as a development service provider for special machine construction.
The starting point of development was the wish of a corrugated board manufacturer to dispense with the usual flow packaging and the use of plastic film. The company launched a competition for ideas, which Michael Baur won. Challenge: bonding without counter pressure and without pressure on the product. In the next step, Michael Baur and his team built a prototype of the newly designed machine. One of the special challenges here was to glue the printed packaging to the top after manually filling it with vine tomatoes: the gluing had to be durable. During the gluing process, however, counter pressure is not possible and, of course, pressure on the sensitive tomatoes must be avoided. An intelligent detailed design was the solution to this problem. The gluing points are applied with a hot glue station, but other processes such as sealing are also conceivable. A station for printing and applying labels has also been integrated into the system. When developing the prototype, Michael Baur attached great importance to flexibility and ease of use. This can be seen immediately from the numerous semi-automatic format adjustments.

Baur uses the lubrication-free drylin SLW linear modules (picture 4) for the numerous format adjustments (see picture 3 below). They combine a torsion-resistant aluminium double-shaft profile with a trapezoidal thread. The carriage travels on drylin liners with incorporated lubrication - a solution widely used in food processing and packaging because no external lubrication is required and product contamination is therefore avoided. Baur uses linear units of the type drylin SLW 1040 in various lengths with hand wheel, position indicator and spindle clamping (picture 4). They enable the operating personnel to quickly change over the packaging system to other pack sizes and formats.
The complete system has a modular design and can work in an interlinked overall system or independently. The compact and slim design also includes the synchronised drive of the folding and positioning units for both sides of the box. It is realised with a flexible shaft, which is much simpler than an electronic coupling. All feeds move in synchronisation with the belt speed.
Both the decision-makers and the machine operators were completely satisfied with the first practical operation. The system fulfils all the relevant requirements.
And the use of the new sustainable packaging does not have to be limited to fresh products. The system can also be used to pack tools, light bulbs, etc. - as a plastic-free and environmentally friendly alternative to blister packaging.