EoW May 2009

english technology news

Drive nuts for measuring machines

Gauder Group has announced the extension of Maillefer’s contract to represent its range of new rotating machines in all CIS countries. Well-known for many years by Pourtier and Setic customers throughout the Russian Federation, Ukraine and Belarus, Maillefer SA Moscow is from now on the representative office for Armenia, Azerbaijan, Georgia, Kazakhstan, Kyrgyzstan, Moldova, Tajikistan, Turkmenistan and Uzbekistan markets as well, in direct collaboration with Philippe Letout, sales manager for rotating machines. Gauder Group – France Fax : +33 1 64 26 61 10 Email : sales.pourtier@gaudergroup.com Website : www.gaudergroup.com Maillefer representative office – Russia Fax : +7 495 362 60 41 Email : vladimir.borisevich@maillefer.net Website : www.mailleferextrusion.com New appointment for CIS countries

The pitch of the drive nut varies in relation to the actual shaft diameter, which is never constant over the entire stroke because the feed distance per shaft revolution depends on the shaft diameter and the pitch angle of the rolling rings. The actual position of the drive nut must be monitored with a precise length scale in a measuring machine, which is standard equipment in such machines. “A release option, operated manually or pneumatically, is an additional advantage for tool adjustment devices,” advises Wolfgang Weber. “Once the drive nut has been uncoupled from the shaft, literally meaning the shaft has been released, the tool or measuring instrument is quickly moved by hand. This prevents damage to delicate components during test sample exchange, and measuring as such is speeded up.” Joachim Uhing KG GmbH – Germany Fax : +49 4347 90640 Email : info@uhing.com Website : www.uhing.com

When developing its drive nut, Uhing conceived a non-positive linear feed element that is successful as a drive element in measuring machines. “The secret is its lack of play, a feature that is fundamentally inherent to the construction of the drive nut,” explains Uhing’s head of marketing, Wolfgang Weber. Drive nuts have three or four rolling rings alternately pushed against the surface of a plain shaft by spring force. These rings connect to the shaft by friction. Skewing the rolling rings results in their rolling off on the surface of the rotating shaft at their pitch angle, thus generating a linear movement. This results in drive nut and shaft acting like a nut and threaded spindle. The spring force required to produce the frictional connection automatically reduces the theoretically existing play to zero, so there is no detrimental effect. The drive nut instantly translates the smallest back and forth rotation of the shaft into a movement to the left or right because there is no system-inherent play to overcome.

Electrostatic powder coating

Model RSC is designed to give an even, finely dosed and dust-free powdering of talc, stearate, lac powder or swellable powder to cables and wires. Strong adhesion and even surface layer is achieved by the electrostatic charging of the powder. The electrostatic also ensures that no powder will fall from the product after leaving the dusting chamber. Depending on extrusion speed and product diameter, up to four powder guns of 100 kV each are used. Schlicht machines can handle product diameters up to 160mm, manufactured to the user’s desired extrusion speed and diameter. Inside the machine is a fluidised powder hopper from which the powder is sucked by pneumatic venturi pumps and blown to the guns. For adjustment of the powder quantity the power of the electrostatic charge can be adjusted from 0kV to 100kV, as can powder quantity and dust cloud speed. Nozzles on the powder gun can be changed to suit the product. An extra-fine dosing device is available as an option. The machine features a fully automatic and maintenance-free filter system, allowing a strong and constant vacuum in the machine; no powder escapes into the environment. Hoses can connect a freestanding dusting chamber to the machine. Rolf Schlicht GmbH – Germany Fax : +49 40 6799 4211

Email : info@schlicht-gmbh.de Website : www.schlicht-gmbh.de

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EuroWire – May 2009