To remedy these problems, HEG installed an Infinity screen printer from DEK International (Flemington, NJ), which works in tandem with DEK's PumpPrint process, giving faster throughput and higher process yields.

With the system in place, production defect rates have dropped to around 25 parts per million, as measured by the company's quality assurance program, which includes 2D inspection, visual inspection, automatic optical inspection (AOI) and electrical test. Throughput for boards that require adhesive application has increased to more than 135 boards per hour, and in excess of 81,000 adhesive dots per hour. This latter figure is well within PumpPrint's throughput capability.

"We need to apply adhesive onto a number of our circuit boards for applications such as automotive electronics and consumer electronics products, including DVD and air conditioning systems," says Wang Chong Ji, chief engineer at HEG. "The main advantage of the DEK Infinity printer is that it is simple. It is simple in structure and simpler to operate than competitive systems. This has resulted in a shorter time for maintenance. Also, DEK Infinity printers have a higher repeated accuracy level than some competitive systems."

Another advantage to the system is its ability to operate under harsh environmental conditions. Specifically, it is unaffected by fluctuations in temperature, humidity and glue viscosity.

For more on PCB adhesive dispensing, call 908-782-4140 or visit www.dek.com.