Optical sensor saves cost in high-bay warehouses

While every care may be taken in the design and installation of an effective mechanical safeguard to prevent push-through, 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 that monitor whether storage surfaces really are unoccupied, so preventing pallets already in place from being pushed backwards and dropping out of the rack.

An additional and urgent problem could be created by pallets that 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.

Practical safeguards

Developing safeguards can be time-consuming and expensive, since each individual rack compartment has to offer protection against push-through. However, advanced photo-electronic sensor technology can be a practical approach, while also bringing financial savings.

Leuze electronic has developed the ODS 96B optical distance sensor, part of a new generation of sensors. This particular model is designed to carry out continuous distance measurements, dynamic product measurement and position controls. With a measurement range of 60-2000mm it is suited to performing 'compartment-occupied' checks and, as an additional feature, a switching function can be used to provide a push-through safeguard.

Thanks to measurement times of just 2ms, ODS 96B photoelectric sensors are said to be able to detect dynamic processes up to five times faster than comparable products. This makes them suitable for use where high-speed sequences takes place, typified by automated high-bay warehousing, where there are fast load-change cycles. It also makes for a tighter grid structure; in other words, more precise and more detailed information with more stable measured values - a benefit that 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 per cent, which also permits faster regulation/setting processes. The combination of measuring and fast and precise switching behaviour in the ODS 96B creates conditions for effective push-through guarding in dynamic high-bay warehouses. It also alleviates potential problems caused by impacting pallets, creating a more reliable, trouble-free operation.

Follow the link for more information on measuring sensors from Leuze Mayser Electronic.