Beckhoff UK explains how a new plasma systems treatment unit, created by Plasmatreat, is using a planar motor system to transport workpieces with greater precision and flexibility.
Plasmatreat GmbH is a German manufacturer of plasma systems for surface treatment and production processes. Its plasma treatment unit is designed to surface-treat a variety of material samples in a two-stage process. During the first stage, the substrate is moved under a nozzle for cleaning and activation. During the second, a separate nozzle applies a functional coating. When designing the system, this where the company focused its innovation efforts. Jochen Stichling, head of design at Plasmatreat, explained: “We wanted a fast, fully programmable, wear-free system to transport the workpieces.”
The best solution found to achieve this goal was the XPlanar motor system from Beckhoff. The XPlanar system consists of planar tiles that can be arranged in any pattern, combined with contactless movers that float over them and can be positioned exceptionally fast, flexibly and precisely. The movers operate jerk-free and are capable of travelling at speeds of up to 4m/sec. They can also accelerate at 2g and be positioned with a repeatability of 50µm – silently and without wear or abrasion. The system supports movement within the x-y space and provides additional functions that allow movers to be positioned with up to six degrees of freedom.
In the Plasmatreat machine, the XPlanar consists of six 240 x 240mm planar tiles and a single planar mover and has eliminated the need for complex six-axis robots and linear motors.
For Plasmatreat, one big advantage of the XPlanar technology is that the plasma jets used to treat surfaces no longer need to be moved and, as a result, can be installed in fixed mountings. The jets are complex, both mechanically and electrically, and the ability to move the workpieces rather than the plasma jets reduces wear to the feed lines. The company identified other additional benefits as a result of the increased flexibility offered by XPlanar. Jochen added: “We can attach a variety of material samples to the mover for treatment using just simple adapters. We can easily add processing stations alongside the plasma jets – markers for good parts, for example, or optical sensing heads to conduct full part inspections – and carry workpieces to them flexibly as needed. XPlanar’s rapid acceleration also lets us move material samples at high speeds; with thin samples this helps minimise treatment time with the fixed jet.”
According to Jochen, the functional benefits offered by XPlanar are proving valuable in a range of applications: “Conventional setups use a six-axis robot or linear motors to move a plasma jet around a stationary workpiece. From a cost perspective, XPlanar comes in somewhere between linear-axis and robotic systems. With flat parts that don’t require much vertical travel on the z-axis, where robotic systems are usually ideal, XPlanar offers a good alternative to gantry-type systems. Its lack of wear, easy cleaning, and clean-room compatibility also offer benefits.”
Jochen believes that XPlanar can optimise plasma surface treatment in two key areas – direct integration of in-line testing for full inspections during the treatment process, and custom-programmable mover travel routes for end customers.
Another advantage identified by Plasmatreat was that it took less than two months to integrate the XPlanar system into its machine. Beckhoff quickly supplied the required 3D data and the electrical connection information that enabled the company to incorporate the XPlanar starter kit into its machine design. According to Jochen, XPlanar has proved to be both robust and reliable. In conclusion, he said: “Another advantage is that the entire plasma treatment cell has now been fully automated using PC-based control, making it a system solution from a single source.”