Linear drive technology aids PCB production throughput

To ensure that the circuit boards have a smooth transition between each process stage, Rainbow Technology used several linear belt drives. However, during the new machine’s initial testing phase, these drives failed.

Fortuitously, as it turned out, Festo had been touring the UK in its electric drives mobile, and the two companies met at a local consultation in Glasgow and agreed an order for two ELGA-RF linear belt drives as an alternative to the original parts, which had failed. Due to the urgency of the situation, Festo configured and dispatched the belt drives to Rainbow within two weeks, as Festo’s Nigel Dawson explains:

“After meeting with the Rainbow Technology team and hearing their needs, we provided them with our new ELGA-RF belt drive axis. As there was an issue with the previous belt drive, we had to ensure fast delivery and precise expertise to limit the risk of any future problems with the machine.

“In order to carry this out, we utilised the sizing and selection software from Festo, Positioning Drives. This software, which is free for customers to download, allowed us to accurately size and select the most optimum solution for Rainbow in a matter of minutes.”

Festo’s ELGA-RF linear belt drive operates the main transport system of the PCB machine and is capable of carrying high loads at speeds of up to 10m/s with high reliability, thanks to the use of robust roller bearings, rather than the ball bearing guides commonly found in linear belt drives. Rainbow Technology’s chief mechanical engineer, Robert Gibson takes up the story:

“The two belt drives were synchronised together to extend the length of travel inside the machine. Here, speed and accuracy of the ELGA-RF belt drives made a big contribution to the final design of the transfer system, as well as the predicted operational lifetime of the parts, which is in excess of five years.”

“It really was fortunate timing that at the time our previous belt drives failed Festo happened to be in the local area. This is our first time working with Festo and we couldn’t be happier with the service and expertise provided. Even with the time constraints we were under, Festo were more than capable to accommodate us, and provide excellent support throughout the whole process.”

The ELGA-RF can handle almost double the payload capacity of conventional roller bearings, capable of carrying up to 160kg. Their robust design guarantees that they are suitable for stop-start motions and their low profile allows them to take up minimal space in the machine.

Rainbow Technology’s new Inner Layer Process Line PCB machine is just eight metres long and is capable of printing 180 double sided panels an hour. With a standard energy consumption of just 4kW, the machine can produce high-density circuits with higher yields and less waste thanks to its novel design and ‘hands free’ automation. Some of these machines are already destined for Asian customers who will make use of them on high-speed production lines.

The method employed by Rainbow’s new PCB machine no longer relies on the use of industry standard dryfilm or liquid resist to create the circuit boards. By using a more economical solvent-free, liquid etch resist, this new approach brings a range of savings throughout the process.

Following this successful first use of Festo’s electric drives in its current PCB machines, Rainbow Technology has commissioned Festo to evaluate the pneumatics on the next generation of PCB machines to make recommendations on how the latter’s parts can be utilised. Robert Gibson concludes:

“We were really impressed with the way in which Festo’s products complemented our machines and fit exactly into what we need. We hope to work with Festo again in the future and we’re excited about continuing this successful relationship.”