Ultrasonics offer a clear advantage
When it appeared photoelectric sensors were unable to meet the demands of high speed sensing of modern, high clarity bottles, engineers at the Highland Spring, needed to look for an alternative sensing method. After discussing the problem with MRG (UK), it was decided to trial a new range of ultrasonic detectors from Contrinex.
Whereas photoelectric sensors look for reflected light and so are susceptible to false reflections, ultrasonic sensors generate a beam of pulse sound waves to sense the passing bottle. This technique provides perfect "vision" regardless of the level of transparency of the target, is unaffected by changes in target colour and is suited to printed or clear plastics or glass without the need to change settings.
The retro-reflexive ultrasonic sensors from Contrinex have a right angled head and are available from under £100. They are available in M18 and M30 sizes and the devices are suitable for applications where distances have to be measured in air, to targets that are solid, liquid, granular or in powder form.
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