Realise precise test device with IEF-Werner adjusting units domiLINE

Optically absolutely convincing

Methods to fake securities or bank notes are increasingly becoming more refined and mostly cannot be detected with the naked eye. Their authenticity has to be quickly inspected by employees of different institutions - such as stores - but also by private persons. A manufacturer of high-security bank notes, identity documents and securities thus developed a software that allows users to examine certain characteristics of a security document by the help of a common smartphone. To check whether this app works from all perspectives, the manufacturer needed a precisely moveable and in all directions adjustable construction. For this, the high-precision linear adjusters of the domiLINE series by the system supplier IEF-Werner are used.

Furtwangen, 19.03.2015 – In the daily use, especially for lay persons, it is often difficult to detect the important characteristics of genuine bank notes. This includes for example the print image, position dependent effects of special colours, watermarks (seeing), the tactility (feeling) and holograms (tilting). Thus a leading manufacturer of bank notes, identity cards and securities develops an app that identifies specific characteristics and thus the authenticity of the security features by the help of image processing. If the characteristics are missing, it is a bank note imitation. This is also important especially for example with foreign currencies or for people with visual handicap. Thereby a common smartphone becomes a fast imitation scanner. To check the reliability of the system during the development, the manufacturer needed high-precision equipment that takes up the documents as well as the smartphone, fixes them and is able to place them in various positions to one another. When it comes to precise handling solutions, the company intensively cooperates already for a long time with the automation specialist IEF-Werner, located in Furtwangen in the Black Forest. “We developed and built corresponding equipment that exactly complies with the requirements of the customer”, Fritz Wehinger, product manager at IEF-Werner, reports. “The basis of the handling solution forms the high-precision vertical axes of type domiLINE.”  

Repeatable precision

The printed products are placed on a supporting surface directly beneath the installed smartphone. Depending on the document, there are two exchange holders with the sizes 244 x 120 millimetres – a plate made of safety glass and an equally large vacuum plate. With this, the printed product is fixed and held safely. The scan process can start. “With our adjusting unit domiLINE we have an adjusting slide in the portfolio, that allows to precisely move the mobile phone to any possible position”, Wehinger explains. For this application the spindle driven system is used with various slide widths. Thereby the user is able to drive any needed stroke. Based on this, all axis configurations are possible – whether X-Y, X-Z or X-Y-Z. For this purpose the slides can be easily assembled on top of each other via connecting sets – completely without mechanical machining. Thus, customers are able to adapt this IEF solution completely to their requirements. The low-backlash of the domiLINE system is ensured by a ball bearing mounted, precise steel spindle in an end plate with pre-stressed plastic nut. The pitches are 0.5 millimetres with domiLINE 30, one millimetre with domiLINE 50, one or two millimetres each with domiLINE 80 and domiLINE 120. The exact positioning is carried out with an adjusting knob that is equipped with a 0.05 millimetre scale. The external slide is manually positioned and fixed with a clamping lever. 

Built up intelligently

On the base plate made of aluminium with the dimensions 500 x 570 x 16 millimetres and slip-resistant adjustable feet, an adjusting unit of type domiLINE with slide width 120 and a stroke of 550 millimetres is assembled via mounting angle. With this, the user is able to adjust the height of the test equipment via hand wheel. To adapt the arrangement to individual requirements, a rotary adjuster of type MDV with electronic position indicator is installed at the slides. Thereby the user is able to put the smartphone in the correct angle manually. Depending on the application, the display can be used for the rotary unit as well as for the domiLINE system. The user is able to read the easily visible absolute position up to two decimal digits. The display can be fastened vertically or horizontally and with an upside down measurement display. The resolution is 0.01 millimetres with linear units and 0.1 degrees with the rotary adjuster. At the rotary unit a high-quality worm gear generates the movements. The MDV is equipped with fast adjustment of the disc as well as fine adjustment and clamping. For this application the adjusting unit has a diameter of 55 millimetres. An integrated headstock locking prevents from backlash in the gear.

An axis combination of two domiLINE guides with slide widths of 50 and 30 millimetres is attached on the adjusting unit. Thereby the user is able to exactly position the smartphone. To adjust the support, the IEF experts installed two further domiLINE units as X-Y-axis combination on the base plate. These have slide widths of 80 millimetres and can proceeding strokes of 200 millimetres. The axes are equipped with hand wheel and position indicator each.

Also the handling was especially important to the customer. “If the slide has to be fixed, when locking common systems frequently problems occur”, Wehinger describes. Since normally the clamping lever is laterally installed. Depending on the position of the slide, this lever may be difficult to access for the user. “Therefore we have created the possibility to clamp the slide on the spindle”, he explains. For the exact positioning, often a similar problem occurs. The slide stands on an unfavourable position, so that the user reaches the adjusting knob only with difficulty. For this, IEF-Werner developed an angled drive. Thereby the user can carry out the exact positioning comfortably.