Posted to News on 2nd Jan 2008, 21:00
Two-way micro inert valve uses less space and power
Smaller components help designers and manufacturers to meet the challenge of producing ever smaller, more compact systems - and this is particularly important for portable instruments, where size and weight are critical. The new Series 300 LFN, two-way micro inert valve from Lee Products is a good example of 'less is more', helping designers to maximise utilisation of the limited space that is available.
This two-way, normally-closed, micro inert valve facilitates higher packing density, enabling more valves to be positioned in the same area, resulting in smaller manifolds and therefore a smaller footprint. The LFN centre-to-centre spacing in 0.30inch (compared to 0.50inch for the previous LFV two-way valve). These valves can also contribute to savings on material costs - for example, if engineered plastics, such as PEEK, are used for the manifold.
Other benefits include less transport volume thanks to the closer spacing, which results in reduced length of the connection passages in the manifold. This can also reduce the amount of reagent needed, while also minimising the transport time of a sample. The LFN valve has a low internal volume of just 13 microlitres and so reduces the amount of fluid needed - which contributes to lower reagent volume and possibly faster throughput.
The faster response time for the valve of 20ms (compared to 30ms for the LFV) allows for greater throughput and the handling of smaller volumes in dispensing applications.
Finally, many instruments have a thermal and electrical 'budget' whereby designers need to size the power supply to handle all the electrical components in the instrument. Lower power consumption is always more desirable and, because more power often means more heat generated, this can be a factor where electronic components need to operate within a limited temperature band.
Cascading benefits
In an enclosed instrument, every incoming watt generates work or heat; the more power a valve draws, the more heat it generates. Reducing the power requirement therefore has a cascading benefit. For example, lower heat output from the valves enables a smaller power supply to be used, which generates lower heat; the possibility of using passive cooling (convection) removes the need for a fan, which would otherwise also add heat and require power. This could be particularly important in portable devices where lower power translates directly into longer battery life, or the need for a smaller battery, leading to size and weight savings.
Typical applications for the LFN two-way micro-inert valve include liquids handling systems used in laboratory, medical, analytical, biotechnology, OEM applications or wherever instruments are being developed that would benefit from space- and power-saving features.
