Engineering News : Page 4 of 10

with a design assist from the Dutch chemical group DSM, has designed what it claims to be the world's first dual-cyclone vacuum cleaner. The design features a patented dual-cyclonic action that separates the dust or water from the incoming air. The advantage: no filter is needed, and the suction power remains at a constant, high level.

The innovative vacuum consists of three different polymers produced by DSM, Heerlen, The Netherlands: Ronfalin(R) ABS, Xantar(R) polycarbonate, and Stamylan P(R) polypropylene. DSM's technical specialists developed a three-dimensional model, then simulated the mold flow for more than 30 plastic parts that make up the appliance.

In addition, DSM formulated the special Fantasy Color that gives the vacuum's housing a metallic appearance. The Ronfalin grade selected combines a very high gloss with excellent flow properties. Xantar was chosen for the reservoir due to its transparency and impact resistance, while the Stamylan P polypropylene's price/performance ratio made it ideal for such components as the filter system.

"Sales in England have been going exceptionally well," says James Dyson, "with a drive now underway to cover the entire European marketplace."

Polymer-based transistor's breakthrough: It's flexible

Thiais, FRANCE -A polymer-based transistor developed here could play a significant role in a generation of products that need flexibility-such as computer and television screens that can roll up and down.

Researchers at the Centre National de Recherche Scientifique (CNRS) have created an organic semiconducting material whose characteristics resemble those of amorphous silicon. They used the material to construct a transistor on which the electrodes are composed of graphite-based polymer ink.

The screen printing methods used in producing the transistor-which is still in the prototype stage-are low cost since they do not require enormous amounts of energy, high temperatures, or vacuums the way silicon devices do. On the other hand, the disadvantage is that they do not have a high resolution so the size of the devices is likely to be many times larger than those currently made of silicon.

Because of its size, the all-polymer transistor will not replace existing silicon-based devices, but is likely to suit applications characterized by high flexibility, low cost, and a large area, says Francis Garnier, research scientist at the CNRS' molecular materials laboratory. It could, for example, be used in information displays on car and plane windscreens because the flexible polymer transistor could be easily applied to the curved form of the windscreen.

Garnier predicts that commercial applications for the all-polymer transistor will be developed in about five years.

Among the initial applications likely is the smart card, he says. Smart cards today are liable to break because the interface between the flexible plastic card and the rigid semiconductor device it incorporates is fragile. This could be solved if the device was also flexible, and the transistor could be the solution, Garnier says.

-Anna Kochan, European Editor, France

Software aids shovel design

Milwaukee-Engineers in the Mining Equipment Division of Harnischfeger Corp. turned to The Mac-Neal-Schwendler Corp.'s MSC/NASTRAN finite element analysis software to ensure the ruggedness of their new P&H 4100 electric shovel.

With a 55-cubic-yard dipper, the

Add new comment

By submitting this form, you accept the Mollom privacy policy.