A leading manufacturer of roller blinds in the USA requested to develop a machine to automatically create quality blinds in PVC-coated screen fabrics. The panels had to be perfectly square and, more importantly, the cuts needed a double seared edge. This is done by first using a hot wheel that rolls over the fabric during the pull, then again with an ultrasonic knife. The customer also required the machine to be compact and easy to use, with automatic fabric feeding and rewinding of the cut panel on the aluminum tube.
Our R&D team designed a machine able to process rolls up to 3,2 m wide. The rolls are placed on a roll holder and fed into the machine by a set of motorized rollers that control the fabric during the full cutting cycle. This creates a precise amount of tension on the fabric during the cut. A clamping system on the rear of the machine rewinds the aluminum bar and the square cut Screen panel.
To ensure the double seared cut, we developed a combined hot air/ultrasonic tool. A hot air blower heats a wheel that rolls over the fabrics before the cut and creates a pre-welded track (3 mm wide) on the Screen material. A powerful ultrasonic cutter then slices the fabric perfectly straight and in the middle of the hot wheel track, searing the cut again. The result is a perfectly cut fabric edge without a trace of fraying fabric.
Perfectly seared edges, great precision.
The biggest challenge was to guarantee the cut's precision, a complex task as the material moves during the cutting cycle instead of laying flat on the worktop. The double set of pressurized rubber-coated rollers before and after the cut ensures that the Screen is straight, perfectly flat, and under the exact amount of tension while being cut to obtain a near-perfect square. We also developed a customized software program to allow for fast and easy preparation of the jobs at hand.
The customer was delighted with the finished product, and the machine has been working in our customer’s plant in the USA since the summer of 2017.