Technical report

An eye for fine details

New laser fork/angled light barriers from di-soric detect even extremely small parts with process reliability

High-resolution laser light barriers from di-soric quickly and reliably detect objects down to a size of 0.03 mm. The laser sensors feature a high function reserve. The automated detection and checking of extremely small components allows users to count on maximum process reliability. IO-Link makes the sensors easy to operate and configure while making them functionally reliable as well. The innovative communication standard opens the door for configuration and predictive diagnostics solutions that save time. By providing the robust laser light barriers, which are also available in stainless steel, di-soric is rounding off the higher end of what it offers in terms of flexible high-performance light barriers.

A feeding unit transports disposable syringes in a hanging position to their final assembly station at high speed. A rotary table is used to fit plastic caps on the syringes. Before this table, the needles pass through a di-soric laser fork light barrier from the OGUL series. The thin needle has to be detected as present before the system is allowed to put the cap on. What's special about this case is that the cannula is no more than 0.3 mm wide. The cycle times are short. Users in the clinical sector rely on the presence of a fully functional disposable syringe in every package.

In an automated assembly process for precision parts, the correct positioning of cylindrical objects is checked using a presence check for an extremely thin groove. While parts are being fed, the high-resolution laser fork light barrier from di-soric detects the position of the groove with functional reliability and with a switching accuracy of 0.01 mm. If the part is positioned incorrectly, the switching output switches off and the object is rejected.

At a compact round table for assembling printed circuit boards, the new di-soric laser angled light barrier from the OGLL series shows what it can do in confined installation conditions. It checks small transistors to see whether the very thin connector contacts are present. The high resolution of the laser sensors guarantees that even extremely thin wires are detected. The easily visible laser light spot allows the sensor to be aligned and adjusted quickly and precisely.

In recent years, automation processes have become faster, cycles shorter and standards more stringent. In applications that need to detect objects or object positions with precision, fork or angled light barriers are the right option. Fork sensors with red or infrared LEDs, such as the OGU series from di-soric, cover a wide scope of functions on their own. Their high switching frequency makes them suitable for detecting small parts with diameters as small as 0.2 mm. In some of these applications, the high-performance sensors are used in places where laser sensors used to be the exclusive choice.

If the objects have diameters of less than 0.2 mm, the sensors with LED light sources from the OGU series may not be up to the task. Especially in cases where users need maximum process reliability. The advantage of laser sensors is that they emit their light in concentrated, straight beams, detecting objects with very high precision. As a result, distances, paths and positions can be measured precisely. Laser sensors are taking over the market for applications that require small details to be detected quickly and reliably. Furthermore, laser sensors feature a significantly higher function reserve when detecting small parts. As compared to sensors with LED light sources, laser variants are always able to produce enough light to ensure functionally reliable switching ─ even in challenging applications.

By introducing the new OGUL and OGLL series, di-soric is responding to the growing need for laser sensors for detecting small parts in assembly, handling and packaging technology as well as in quality control. di-soric is currently the only provider offering laser fork light/angled light barriers that detect objects down to a size of 0.03 mm with process reliability. The thin and easily visible light beam from the non-hazardous laser class 1 makes it possible to detect extremely small parts through narrow slits and holes. The position and alignment of thin wires, drill bits or cannulae can be defined down to a (reproducible) accuracy of 0.01 mm.

The new laser fork/angled light barriers are compact, structurally identical and backwards compatible with the OGU series with LED light source. Thanks to their powder-coated metal housing, they are extremely robust (IP67). The light barriers are functional within a temperature range of minus 25 to plus 60 degrees Celsius. They are available with fork openings of 30, 50, 80 and 120 mm. Where there are stringent requirements for hygiene and resistance to cleaning agents, the cleanroom-approved di-soric stainless steel designs are used.

The new laser fork/angled light barriers are an advancement of di-soric's proven dual-operating concept. The user has the choice They can use IO-Link for convenient configuration of all sensor functions, including four optional sensor modes. The user also has the option to manually adjust the switch point using a potentiometer. The sensors have been outfitted with a push/pull output. PNP and NPN functions have been combined into one device.

IO-Link offers a wide variety of completely new installation advantages. It also provides high-performance parameterization and predictive diagnostics concepts in addition to simplifying operation considerably. Standardized wiring and plug connections reduce installation and commissioning times considerably. The configuration of the light barriers based on centrally stored parameter data and recipes allows for quick batch changes. The sensor can be configured using the IO-Link master or a control panel. All settings can be applied to the sensor directly via drag and drop using a control panel. Even device replacement can be carried out quickly and easily with IO-Link and data storage in the master without any expert knowledge.

For optimal adaptation to the application, the laser fork/angled light barriers can be operated in four sensor modes. The user selects the specific mode that is best for fulfilling the task at hand: When the STANDARD factory settings are used, the resolution is 0.05 mm and the sensor operates at a switching frequency of 5,000 Hz while offering a high function reserve. Where speed is a priority, SPEED mode offers a switching frequency of 10,000 Hz (a 100% increase). This creates the optimal conditions for fast process sequences. The POWER setting gives you added transmitting power and maximum function reserve. The HIGH RESOLUTION sensor mode is designed specifically for detecting extremely small parts. At a resolution of 0.03 mm, a reproducibility of 0.01 mm and a switching frequency of 2,000 Hz, it is possible to detect extremely small parts.

System operators who choose IO-Link opt for an internationally standardized automation system that upholds the IEC 61131-9 standard. IO-Link opens the door to application-specific configuration and does not require specific hardware. IO-Link gives the system operator a transparent picture of what is going on at the process level ─ at any point in time. The intelligent communication interface is integrated into the sensors. It opens up a versatile range of options for qualitative and quantitative diagnostics. The operator can control, monitor and maintain the device remotely. They can also compare measurement and threshold values at any time to assess whether the application is working and how reliably. IO-Link is the technical "catalyst" for Industry 4.0 and represents versatility, flexibility and the increased performance capacity of the new laser fork/angled light barriers from the OGUL and OGLL series.