EoW May 2009

english technology news

Automatic measuring gives better results

measuring wall thickness (stranded wire)

The special design uses twist-optimised compensating elements, and the mechanically strong fibre optic cable is robust even with rotary angles of +180° on a robot arm. Chainflex CF Robot-LWL cable has been tested for more than 1 million double cycles, with no change to data transfer rates even at a torsion angle of 360°. The cable is suitable for industrial applications for image transmission for GigE, FireWire IEEE1394a/b and USB. Accurate wall-thickness measurement is essential for final product performance and to avoid waste; if the minimum wall-thickness is too small, the cable has to be scrapped. iiM AG – Germany Fax : +49 3693 88585 11 Email : info@iimag.de Website : www.iimag.de Calculation inaccuracies in wall-thickness and concentricity can be overcome by the use of an automatic measuring device, such as the VisioCablePro system from iiM. It measures the smallest wall and other wall-thickness minima without operator input in the process, or in lighting or optic focusing. The operator is only concerned with preparing the sample.

Central to quality in cable production is the measurement of wall thickness, especially at the narrowest point that forms the basis of the calculation of that other important feature, concentricity. It is important that this measurement is determined accurately and that it is appropriate for the cable type.

Bus system problems often occur during twisting applications in energy chains, particularly with shielded data cables if the shields get damaged or open up. This is not the case with glass fibre optic cables, which do not have a mechanically vulnerable shield braid, and are insensitive to EMC whilst transferring high-speed bus signals up to a length of 400m. igus GmbH has developed a twistable fibre optic cable for all 3D movements in energy chains, to keep bus systems working reliably. The twistable TPE fibre optic cable, Chainflex CF Robot-LWL makes high data rates possible and can be routed directly alongside high-capacity electrical power cables. In determining the wall thickness, it is necessary to take measurements at 60° intervals around the cable, as shown in the diagram. It can also be seen that the narrowest parts of the wall are not necessarily uniform. This makes manual measurement difficult for the operator with the responsibility of the measuring microscope or profile projector, and can lead to an arbitrary or subjective technique and uncertain results. Twistable optical fibre cable

igus GmbH – Germany Fax : +49 2203 96 49222 Email : info@igus.de Website : www.igus.de

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EuroWire – May 2009