Equipment designers must frequently incorporate miniature solenoid valves into their pneumatic designs. These valves are important components of medical devices and instrumentation as well as environmental, analytical, and similar product applications
The industry is constantly facing pressure to produce increasingly more miniature, solenoid valves. But with each step towards a smaller valve the design and valve application process becomes more complicated. Engineers have many aspects to consider and must balance the need for reliability, extended service life, and standards compliance against often-contradictory performance requirements such as light weight, high flow and optimum power use.
All of these requirements are critical for common applications and new valve technologies may lessen or eliminate compromises.
Just one valve not performing to specification during a process can cause worthless output and scrap product which wastes a lot of money. Generally, the further into a design a reliability issue is found the more expensive it is because when a product or design is changed only slightly the testing process must start all over again.
Most miniature solenoid valves have internal elastomers that can swell when dealing with gases. If the design doesn’t compensate properly then in time, swelling can change performance parameters to the point of rendering the valve inoperable.
Well designed valves consider the valves performance changes due to chemical and/or compatibility effects.
A long lasting valve is extremely desirable and in some applications, critical. Longevity can be difficult to attain due to breakdown of the dynamic seal. Overtime the poppet in a valve wears down, a few manufacturers use innovative poppet designs to counteract wear.
Plastic-bodied designs have been used to tackle the problem, these offer a smoother surface finish and less friction than metal-bodied valves, which reduce poppet wear. The overall success of these solutions can depend on conditions such as the media selected, the length of time the valve is Find and the limits at which it’s used.
Critical in portable devices as every gram counts. A decrease in valve mass allows designers to increase other things such as battery mass for more power or a longer running time.
Plastic bodies have been used in miniature solenoid valves to achieve lighter valves in place of stainless steel.
Attaining higher flows or lower power consumption can both add to valve weight.
Designers are researching innovative valve designs that find new ways to balance these considerations with acceptable weight reductions.
Higher Flow Rates
Whilst minimizing designs, performance must still be optimized. Increasing airflow rate in a miniature solenoid valve can be an important step.
There is a thin line in miniature valve design between power, pressure and flow. A boost in flow rate can make a huge performance difference.
Higher flows need the largest possible valve orifice but also demand higher valve power and often, larger valves. Designers are trying to produce more efficient designs with higher flows that are still light weight and small in size.
Critical in portable devices that are battery powered. Consumers want a miniature solenoid valve offering optimized power at the same or lower valve weight, to make the most out of every amp-hour of energy a battery can generate.
Many of the valves on the market have high power performance needs. The latest innovations are looking at features such as low watt, more efficiently designed coils. This may extend battery life or increase battery size and device performance.
Selecting miniature solenoid valves for the design of a given device usually involves finely balancing tradeoffs among competing pressures for reliability, service life, light weight, higher flow, optimized power use, standards compliance, and more. Fortunately, newer technologies have reduced the compromises while increasing the performance. New miniature solenoid valve technologies represent the fusion of several innovative approaches to meet the widest possible range of demands from knowledgeable designers across multiple industries
ASCO have a range of Micro-Miniature Solenoid Valves which are used for the control of fluids and gases in medical equipment, analytical instrumentation, and industrial applications.
- Miniature general service valves
- Miniature isolation valves
- Miniature pinch valves
For more information on ASCO’s Micro-Miniature Solenoid Valves click here