Leading manufacturer of high-speed packaging machinery has chosen the outstanding performance, accuracy and reliability of Control Techniques’ servo drives for its latest vertical form fill seal machines.
The latest vertical packer was designed to meet demanding customer specifications in terms of performance, reliability, flexibility and ease-of-use. The four brushless Unimotor fm servo motors controlled by Control Techniques’ Digitax ST servo drives, mounted in alignment, generate a mechanical speed of more than 165 pillow packages of 16.5X12 in. (420x310 mm) per minute and more than 80 four-seamed, square-bottom packs per minute up to a maximum film band of 59.25 in. (1505 mm).
The Digitax ST range has been designed to meet the requirements of both machine designers and system integrators - a compact servo drive with an unmatched range of flexible integration features, optimized for servo applications requiring high peak torque, exceptional dynamic response, faster installation and start-up as well as ease of integration. Four product variants make up the range at launch - Base, Indexer, EZ Motion and Digitax ST Plus.
Variable speed drives from Control Techniques play a crucial role in the production process – wherever precise motion control is required, from portion control and assembly, through to the packaging and palletizing sections.
The ice-cream is produced from a range of ingredients including cream, sugar and flavorings, then mixed and frozen. Special-purpose machines, along the line, portion and shape the ice-cream and add additional components, including chocolate or fruit-juice coatings, and insert the stick. The completed ices are wrapped and sealed and packaged prior to palletizing ready for dispatch.
At each stage, Control Techniques' drives provide the precision and control for the multi-axis machines. For example, a six-axis machine provides the exact portioning of each ice-cream, using a flying-shear cutting technique, with cam software ensuring that the correct length, speed of flying shear and right angle is achieved. A fine tolerance must be achieved in order to maintain the minimum weight required for portion control and this target was achieved with the help of a Control Techniques engineer.
Further machines with Control Techniques multi-axis servo control include packaging machines that plastic wrap, seal and insert the ice-creams into boxes.
The latest custom cheese cutting machine provides precision portioning of blocks of cheese that weigh up to 187 lbs. (85 kg). This has drastically cut the time for the task and gives accurate and repeatable results every time. The control and accuracy of movement of the blocks of cheese through the machine is attributed to the choice of general purpose AC drives from Control Techniques.
The Control Techniques’ motor control solution is a high specification, general purpose AC drive, packed with features in a compact size that takes up little room in an enclosure. Featuring integral dynamic braking as standard, the drive has the ability to absorb the energy created by fast stops, as in this case, whilst giving very smooth, precise control of off-the-shelf motors. The drives on this cheese cutting machine are hard-wired into the PLC controller to give a fast digital link and are simply programmed to give smooth acceleration and instant STOP, when they individually receive instructions to do so.
The problem of increasing downtime and soaring maintenance costs on a Pizza production line has been solved with the installation of variable speed drives, motors and gearboxes from Control Techniques.
A high throughput baking, cooling and packing line for pizza bases was suffering from a significant drop in production because of repeated mechanical breakdowns. An average loss per week of 4.5 hours production time, equated to a reduction in output of some 8,000 pizza bases — a loss of over $2,348 (€2,000) in product! The weak point in the line was proving to be a series of nine 30 foot (10-metre) long conveyors that take the cooked bases through an air-cooled section prior to packing. Three meter long drive shafts for each of the conveyors were being driven by a system of chains and sprockets from one large geared motor, with very high torque. Frequent jams, caused by a dislodged pizza and the consequential build-up on individual conveyors resulted in broken drive shafts.
Knock on effects were a halt to production and high maintenance costs as new, tailor-made drive shafts had to be specially machined to replace the broken ones — amounting to high annual maintenance costs of around $4,110 (€3,500).