MiniMags – Microtechnical Challenges Miniaturizing Electro-Magnetic Valves

Inhalt:
Automation industry shows substantial interest in micro-actuators which are integrable within technical systems. Actuators for groundbreaking systems have to be exceedingly small while working efficiently in order to avoid intolerable heating. Valves are widely-used products in automation industry, for which the reduction of designed space (and thereby the system's mass) and the enhancement of performance are claimed. Miniaturization is essential for the application in new fields. Pneumatic valves are often designed as modular systems wherein each component fulfils a certain function. Miniaturizing magnetic valves comes along with downscaling electromagnetic coils. Due to scaling, the resistance of the coil increases, leading to higher power losses and thus to an unfavourable heating of the system. At the same time, the material’s saturation is reached earlier because the cross-sections of yokes decrease. Those facts have to be taken into account for the application of magnetic actuators in micro-systems. One possibility in order to compensate these limits is the optimization of the magnetic circuits. On one hand, the valve can be optimized to a minimal designed space – especially to minimal mounting dimensions for valve clusters. This approach is followed by designing a new magnetic microvalve for valve clusters in industrial pneumatics. On the other hand, the valve's power losses can be minimized – by designing a mini-valve operated in resonant mode.