Pixargus GmbH, Automation by Vision

Pixargus: First all-side inline inspection of window profiles

At “K 2010”, Pixargus will introduce the new generation of PSP 6 systems capable of simultaneously inspecting the surface of profiles from all four sides. They capture even the most minute irregularities of the surface during ongoing production – without a gap and objectively. This guarantees that only perfectly flawless profiles are shipped. Users of the system avoid complaints and related costs.

Surface defects in window profiles hardly ever affect their functionality. However, they often give rise to complaints, forcing the manufacturer to grant discounts. And once a profile or a window frame has been manufactured, the consequential costs are significant.

In production lines for window profiles or installation channels, optical inline surface inspection now provides the possibility of capturing the complete surface and immediately sorting out any out-of-spec material. Moreover, the operators notice trends at a glance and can intervene before a problem occurs.

The systems of the ProfilControl-Surface series for optical inline surface control detect and classify isolated defects, such as pickles, bubbles, breakouts, foreign particles or holes, or elongated defects, such as grooves, edges and misruns, in real time.

PSP 6 checks profiles with a maximum width of 120 mm that fit into an enveloping circle of a maximum radius of 180 mm. The system can handle profile speeds of more than 60 m/min.

At “K 2010”, Pixargus will introduce the PSP 6 system fitted with two individually adjustable motorized sensor heads for two inspection levels and two sensor heads with motorized height adjustment for inspecting four sides at the same time. Thanks to these features it is possible to have four completely variably arranged inspection levels suitable for the specific profile cross section on hand. For example, one camera may inspect the complete upper side of the profile, while a second one is checking the profile edge.

Pixargus illuminates the profiles with an LED line, an in-house solution specifically developed for these systems. Outstanding features of these systems are their high light density and long service lives. Cameras with a resolution of 50 µm or better “see” every element of the surface area under optimal light and viewing angles, recording a complete and detailed image of the surface.

A newly developed autofocus and the automatic lighting control ensure optimal image quality independent of the profile shape and surface structure.

As soon as the system detects a typical defect or an undesired groove, the position of the defect is automatically marked. Thanks to this, the human operator doing the final inspection may concentrate all his attention on the marked areas. The surface defects are displayed on a touch screen, complete with information such as type, position or size of the defect, and stored in a log file.

As an alternative solution, the Pixargus system can be used to control sawing and sorting equipment and introduce an automated sorting process. This saves costs and optimizes the production process, which becomes more reproducible and stable.

The system is entirely operated via a touch screen panel. All functions can be extremely easily and intuitively set. With the large, clear buttons on the touch screen the operator easily navigates through the operating menu.

The basic version of the Pixargus system comes with two cameras, for example for inspecting the upper and lower sides of a profile. All systems are prepared to accommodate two additional, individually adjustable cameras.

Pixargus has given the system an extremely compact design, as in extrusion lines the space available for the installation of inspection systems is usually very limited. The inspection system requires an installation length of only 500 mm in the production line. The system is of a sturdy design to withstand the prevailing environmental conditions during production.

Undetected surface defects give rise to complaints: With permissible defect rates of only a few per mill, each wrongly classified part leads to a lower supplier rating and has consequences for the placement of orders in the future. Therefore it is important to be able to reliably sort out material with surface defects. This is only possible if the entire surface is checked – along the complete product length and from all viewing angles.

During the last few years line speeds have increased dramatically, making visual final inspection an increasingly difficult job. Under these conditions, it is impossible for the human eye to detect defects with sufficient reliability, over both short and longer periods. Moreover, it is a proven fact that after some time a human inspector will always – unintentionally – classify small defects as large ones and minor defects as severe ones. Likewise it is impossible to visually inspect the profile from several sides during running production.