Long stop

Camcon could change the face of actuators with a low-energy device that is 20 times faster than existing technologies. It has already completed 11.5 billion operations – and is still running. Jon Excell reports.

A low-energy binary actuator capable of staggering speeds and with exceptional longevity could revolutionise the fluid control industries, its creator has claimed.

Cambridge-based Camcon chief executive Wladyslaw Wygnanski said it could do for the gas and liquid industries what the transistor did for electronics, and could be used to replace existing actuator and valve technologies in a wide range of applications.

One area he feels the device could make its mark is in insulin dosing for diabetics. Clients in the aerospace and automotive industries are also looking seriously at the device.

To explain how it works, Wygnanski drew an analogy with a clock pendulum held in place by a magnet. A brief electric pulse would release the pendulum which under its own energy would travel to a magnet placed on its opposite side. In other words, one electric pulse would send the pendulum from position A to position B – hence the term binary actuator.

In Wygnanski’s design a sprung armature is held in one of these two states by permanent magnets, while an electromagnetic coil is positioned with its axis perpendicular to the direction of armature movement. The coil requires electrical energy only for a fraction of a second to disrupt the magnetic field created by the permanent magnets, allowing the spring to move the armature.

Wygnanski estimates that around 80 per cent of the energy required to operate the actuator is provided internally by the sprung armature and the permanent magnets.

This extremely low external power requirement means that it can be driven from a single battery over an extended period, making it ideal for remote applications where there is little or no access to a power supply.

Another consequence of this low energy demand is low heat dissipation, a valuable property when managing the flow of low-temperature liquids and gases, or in situations where many actuators need to be packaged in a confined space.

Once the energy is applied the armature accelerates quickly, cutting through the magnetic field. As the armature moves to the opposite pole it decelerates to a standstill, giving it a ‘soft landing’ reducing impact stress to both it and the pole pieces.

Coupled with its ability to perform 20 times quicker than the fastest current valve systems, the low-impact nature of the design is one of the main reasons for Wygnanski’s confidence.

A pair of Camcon’s actuators recently completed more than 11.5 billion operations – and they are still running. With each actuator driven at around 30,000 changeovers per minute, and neither showing signs of wear, Wygnanski is understandably proud of this achievement.

With conventional valves working for about 10 million operations, he claimed that 11.5 billion puts Camcon’s device ‘in a different league’.

‘My initial estimate was one billion. Now I’ve reached 11.5 billion and it’s still running – let’s see how far it will go.’

Though Wygnanski would personally like to see the device make its mark in the medical field, its potential in a variety of industries makes it difficult for him to focus on just one application, he said.

However, non-disclosure agreements prevent him from discussing specifics about other potential uses.

Camcon recently received a £45,000 DTI Smart award for a feasibility study aimed at reducing greenhouse gas emissions from gas and liquid fuel turbines.

It is thought that the actuator may be capable of achieving the speed and accuracy required to help turbine engines run in ‘lean burn’ mode, an efficient yet notoriously unstable method of limiting Nox emissions.

While use of the actuator in an aircraft jet engine is years away, Wygnanski said that more down-to-earth applications will be on the market this year.

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