Office desktops, shelving, countertops – furniture derived from timber planks is a part of everyday life. In order to ensure that the roughly sawn edges of regrown, raw material are suitable for furniture manufacturing, the edges need to be banded in machining centers. At IMA Klessmann of L¸bbecke in Germany, Advantage 60/70 machines process laminate between eight and 60 mm thick using thin, thick or solid wood edges to produce finished furniture elements. These decorative edges are then attached to the milled cut edge of the timber. The first stage of processing entails fixing a separating agent to the decorative surface of the laminate. A bonding milling unit mills the edge in both longitudinal and transverse directions, in order to remove even the minutest grooves from the edge. This results in a smooth adhesive surface for fixing the decorative edge.
|In the multifunctional unit valves and cylinders are supplied assembled as a complete unit and fitted with Plug-&-Work-piping.|
The right feed
Advantage 60/70 machines work with a feed of 16 meters (52 feet) per minute. Even at high speed, the workpiece and decorative strips are fed accurately to the bonding unit. The workpiece is heated up and travels past the adhesive spreading roller, which releases the hot-melt adhesive at the edge. Holding rollers then press the strip firmly against the wooden edge. Heating up the edge prevents the adhesive from cooling too quickly, thus helping to achieve optimum adhesion. Since the quantity and type of adhesive required varies based on whether the strip is made of plastic or solid wood, the Advantage 60/70 has a quick-lock system, permitting a swift change of adhesive container. A pneumatically controlled bayonet closure forms a secure interface between glue and adhesive mechanism.
|The HF04 valve support system is ideal for applications requiring a high throughput rate in a confined space.|
A pneumatically driven knife removes any excess material on the edges. With a clean cut, any projecting length on the front and rear edges, or cover strips of the workpiece, is then reworked with precision. Rexroth PRA cylinders are used for the workpiece feed, controlled by an HF04 valve unit. For the knife, Rexroth supplies valves from the TC15 Series and 523 Series cylinders, assembled as a complete unit and fitted with Plug-&-Work-piping. “By using pre-assembled power units we save valuable assembly time”, reports J¸rgen Kleine-Beek, Developer at IMA Klessmann. “Apart from this we are also able to reduce our logistics costs. We rely on a strong partner to supply us with reliable components.”
The multi-functional power unit of the Advantage 60/70 from IMA, offers the customer decisive benefits. The upper and lower edges of the workpiece are finely milled and the front and rear edges copy milled in a single work process. This complete machining phase is undertaken using only two motors. An ED02 electropneumatic pressure control valve from Rexroth ensures that the unit is fed gently towards the workpiece. This pressure control valve also permits a swift response when the command value changes. The machine control specifies an electrical command value, which the ED02 then converts into a pneumatic pressure.
|The compact design of the ED02 pressure control saves valuable space.|
“Using the compact ED02 electropneumatic pressure control valve enabled us to save the customer installation space. Where formerly four individual valves and various pressure controllers were used, you will now find a single ED02,” reports Markus Heidemann from Ingenieurb¸ro Heidemann. “Together with Rexroth we have overhauled the pneumatic control sequence”, adds Kleine-Beek. “Applying the new products from Rexroth was particularly interesting for us. They are compact in design and we were also impressed with respect to their power density.”
The compressed air for the complete pneumatic system in the machine is provided by an AS3 conditioning unit. “We are intentionally using lots of pneumatic components in the machines, as they offer an economical, robust and reliable option for the drives”, explains Kleine-Beek.
The perfect finish
In order to be able to machine different edges, the Advantage 60/70 is equipped with a swift exchange system. The Series CCI compact cylinder is used for controlling this power unit. The workpiece is transported by an eLINE-ball bushing guide. This is ideal for economic assembly as it is self-supporting. Thick and thin edges are reworked using a flat scraper. The perfect finish is achieved for all machined workpieces using a polishing machine, which gives the edges a final clean and polish – for a perfect piece of furniture.