Constant torque even on small diameter reels

NARROW WEB, inspection and rotary die cutter slitter rewinder manufacturer Bar Graphic Machinery has underpinned its engineering capabilities by introducing unwind tension control technology that can maintain constant torque on reels even of small diameter. The company believes that incorporating Merobel EMP brakes and PowerBlock2 power supplies into its machine design will give the company a competitive edge.

Other equipment designed and engineered by Bar Graphics includes re-register die cutting, re-register flexo converting and finishing. The company says that one of the keys to its successful performance in the market place is its ability to be flexible when it comes to customising a customer’s equipment.

The Merobel EMP electromagnetic brake works on the following principle: a change in the magnetic field alters the viscosity of the EMP powder, controlling the mechanical coupling between the inner and outer rotors. With this technique, the torque is proportional to the current that produces the magnetic field and is independent of the rotation speed. The torque/size ratio is better than for a friction-based mechanical solution and better than a servomotor; less reliable for small torques. The torque generated is consistent and reproducible, without shocks, and the response time is rapid. Wear is also very low, ensuring a long maintenance free lifetime.

In addition, Bar Graphic Machinery has included in its machine design Merobel’s PowerBlock2 power supply. This ensures very precise electrical control thanks to a closed-loop-controlled output current based on microcontroller technology. PowerBlock 2 has a high level of protection against transients (short circuits and circuit openings) and is very easy to set up.

Another key point, says Bar Graphic Machinery chairman Bill Rhodes, is that the EMP brake and clutch range is eco-friendly. It is dustless by design as there is no loss of magnetic powder outside of the internal working areas. Recently, particular attention has been paid to quiet operation. Specific surface treatment characteristics as well as the exact powder composition help to improve the natural noiseless trend of EMP technology. “We are really involved in our product maintenance and after sales service, so we didn’t want any pollution from this system,” explains Bill Rhodes.

Later this month Bar Graphic Machinery will show its latest digital finishing and converting line at the next LabelExpo (stand 6G128) in Brussels. The BGM Elite FDTR flexo die cut is able to start and stop producing little if any waste. Other standard features include the ability to print to re-register, die-cut to print re-register and print to print re-register; the servo-driven print stations are equipped with self-positioning print cylinders enabling automatic print registration set up. Other models to be exhibited from the Elite Range will be a filmic inspection slitter rewinder, inspection slitter rewinder, rotary die-cutting rewinder and die-cut to register slitter rewinder. Bar Graphic sells its machines throughout Europe mainly, via a network of international resellers.

The Merobel equipment was supplied to Bar Graphic Machinery in the UK by reseller Andantex.

Andantex Tel: 024 76307722