Molded peristaltic pump is inexpensive, micro

Two German companies are commercializing an inexpensive injection molded micro pump for a variety of medical applications such as laboratory analyses.

"The pump can reach very low volumes ranging from a few microliters to a few milliliters per minute," Erik

Aussems, a developmental engineer at DNE GmbH (Schnaittenbach, Germany) told Plastics Today. The other partner is 2E mechatronic GmbH (Kirchheim/Teck, Germany).

A benefit of the new technology is the combination of the peristaltic principle with cost-effective modular construction of plastic diaphragm pumps. The companies say the target price for the pump is less than 10 Euros (less than $13.33).  

A peristaltic pump contains a flexible tube that performs both the suction and the compression of the liquid to be filled. It can be cleaned by just changing the tubing. That's an idea that's growing in interest in the medical field as regulations are becoming more difficult and expensive to comply with.

Polyester  and acetal

Aussems said the pump is molded from PBT-type polyester and polyacetal.  A prototype was shown at a recent German medical show. Production will start with one-cavity tools in presses ranging from 20 to 50 tonnes in clamp force.

Features of the micro pump include:

"At this moment, there are no electronic circuits integrated into the pumphead or pump actuator," said Aussems. "The pump is activated by a DC motor, brushless or with brushes, depending on the required lifetime. The speeds, and thus volume, are adjusted by using the right gearbox. Fine tuning can be done by adjusting the voltage of the motor." Nominal voltage is 12V. 

The minimum or maximum volumetric flow ratios are dependent on the type and size of the shaped hose. The same applies to the requirements regarding material resistance, the achievable intake pressure, the maximum pumping pressure and the long-term behavior of the pump.

The pumps can be adapted to individual customer requirements based on a specific application, Aussems said. For varying volumes, a different gearbox and/or different tube can be installed. Air can be pumped as well liquids. The output pressure can reach up to 5 bar.

Possible applications of the micro pump in medical technology are:  laboratory technology, analysis automation, diagnostics, and lab-on-chip technology.

2E mechatronic GmbH was founded in 2002 and first began molding interconnect devices in 2003. Among the products manufactured by 2E are male multipoint connectors, customized connectors, connectors, and precision injection molded housings. DNE is a specialist in microfluidic parts.

2E mechatronic and DNE plan to develop a production facility in southern Germany.