Push-through guard using measuring sensors in automatic high-bay warehouses

Leuze: In high-bay warehouses, protection against accidental push-through of pallets is generally provided by mechanical solutions involving elaborate steel constructions. With its ODS 96B optical distance sensors, Leuze electronic is offering a more economical and technically superior solution to address this important safety requirement.

Not only is the effort and expense involved in equipping each individual rack compartment with an effective mechanical push-through safeguard enormous, but the impact generated by dynamic loading processes exerts a negative influence on the rack system itself. This can be prevented initially by providing a compartment occupied check using suitable sensor systems, which monitors whether storage surfaces really are unoccupied, so preventing pallets already in place from being pushed backwards and dropping out of the rack. However, an additional and urgent problem situation is created by pallets which are skewed or offset. During highly dynamic operating processes, system-specific tolerances can be quickly exceeded, resulting in the forks of the rack handling system displacing already positioned pallets when performing inward and outward movements – with potentially disastrous consequences. ODS 96B optical distance sensors from Leuze electronic provide an economical and effective push-through guard which at the same time ensures maximum care of the rack system itself by preventing mechanical loads caused by impacting pallets.

Optical laser distance sensors ODS 96B from Leuze electronic operate using the triangulation principle, making use of CCD technology for evaluation. They are designed to carry out continuous distance measurements, dynamic product measurement and position controls. Their measurement range of 60 to 2000 millimetres makes them ideally suited to perform compartment occupied checks, and as an additional feature their switching function is now used to also provide a push-through safeguard.

Thanks to measurement times of just two milliseconds, ODS 96B units are able to detect dynamic processes up to five times faster than comparable products. This permits high-speed sequences in the interests of fast load change cycles, but also makes for a tighter grid structure, in other words more precise, more detailed information with more stable measured values – a benefit which enhances system efficiency particularly when working with shiny, structured or dark surfaces or in fluctuating temperature conditions. With its high-speed measured value sequence, the ODS 96B provides high repeat accuracy rates of ±0.5%, which also permits faster regulation / setting processes.

The combination of measuring and switching functions in the ODS 96B provides the conditions for this contemporary form of the conventional push-through guard. But under the bottom line, the exceptionally fast and precise switching behaviour of the Leuze sensors also fulfils the demands of dynamic operation in automatic high-bay warehouses in terms of economy, safety and availability.