Small, smaller, smallest!

The innovative sensors with a big sensing range. Justin Cunningham reports

Tiny sensors are often required for precise monitoring of very small objects. Unfortunately, many of these small sensors also have short detection ranges and that means they cannot be used reliably or consistently. To overcome these problems, Contrinex has come up with one of the largest ranges of miniature inductive and photoelectric sensors. These come with standard, double and even triple detection distances from devices as small as 4mm diameter. Contrinex prides itself on being a solution provider for applications where conventional sensors are not suitable. It produces a wide range of sensing equipment, from conventional standard inductive and photoelectric sensors to more specialised high performance devices. The 4mm diameter sensor series, with a 2.5mm sensing range, is said to be ideal for installation into tight places and enables good working clearances from detected products. The company also claims to make the smallest inductive sensor in the world at 3mm diameter. Despite being very small, these sensors have a relatively long 1mm sensing distance and include vital short circuit, overload and inverse polarity protection. They also feature a tough stainless steel housing and hi-flex polyurethane cable that makes them ideal for operation in harsh conditions. Quite often for a photoelectric detection solution, the only option available is to use fibre optics linked to an amplifier. However, fibre failures can be the bane of manufacturing and are frequently the cause of costly stoppages on the production line. As an alternative, Contrinex makes a miniature photoelectric range of sensors with high performance. The 4mm diameter photoelectric sensors come with diffuse of through beam formats and in short stainless steel housings. Contrinex claims the initial cost of these compact photoelectric devices is less than a fibre and amplifier arrangement and adds that there is no need to find a safe location to mount an amplifier. Additionally, the connecting cable of these self contained discrete products can be turned through a much tigher radius than a fibre, so can be more easily embedded and protected. The diffuse sensors have a long 50mm sensing range and a through beam set up of 250mm. Both of these longer sensing distances help to ensure reliable part detection in production environments.