Non-contact transfer does not damage surfaces Non contact transfer units handle different kinds of surfaces without damaging them, such as hot, cold, uneven, sensitive, dirty or even porous surfaces. Bosch Rexroth's Non Contact Transfer (NCT) series units enable designers, makers and users of automation systems to handle products with all kinds of different surfaces without the risk of damaging them. The units use the Bernouilli principle and a positive pressure air supply provides the non-contact lift.

As a result, products with hot, cold, uneven, sensitive, dirty or even porous surfaces can be lifted safely with ease.

'The NCT range provides a solution for those tricky handling problems where mechanical grippers or vacuum cups would certainly have caused damage to delicate and expensive products', said Stuart Cheyne, product manager for Bosch Rexroth.

'Not only do the non-contact transfer units succeed in previously virtually impossible applications, they do it without the need for any extra equipment to create a vacuum supply, such as vacuum pumps or generators'.

'This gives our customers a total solution that is highly compact, has no wearing parts at all and only needs a supply of clean, dry compressed air.' The development of NCT technology was driven by the needs of the semiconductor industry to be able to handle expensive silicone wafers carefully and without contact.

Having been successful in this sector, the main benefits of the technology quickly transferred to other industries facing similar handling problems including pharmaceuticals, food and printing.

Notable applications include: handling CDs and DVDs; picking optical lenses without touching the main lens area; and lifting 'leaky' objects such as electronic printed circuit boards peppered with small perforations.

Paper and plastic bags are also being processed using this technology.

The NCT units use Bernoulli's principle that in essence states that as the speed of a fluid increases, the pressure within it decreases.

The principle is often demonstrated by blowing between two sheets of paper and witnessing the higher external pressure push the two sheets together.

Bosch Rexroth's NCT units harness this principle.

Positive airflow under the device creates a lifting force between the centre and circumference.

Thanks to the continuous air flow, the lifted object never actually attaches itself to the NCT surface, allowing precision handling of delicate items.

Also, because there are no moving parts, NCT units offer a true non-wearing solution.

The NCT range currently comprises four different sized units measuring 20, 30, 40 and 60mm diameter.

Corresponding lifting forces at 5bar are: 0.9, 1.3, 2.0 and 6.0N.

Consequently, the maximum lift capability is 900g.

Depending on size, the weight of the anodised aluminium units ranges from 0.02 to 0.124kg, while air consumption ranges from 100 to 210lit/min.

Working pressure for the non-lubricated compressed air supply is 1 to 7bar.

Ambient operating temperature is 5 to 60C.