Electro-fluidic systems are devices managing fluids (air, gas, liquids…) such as servovalves, pumps, electro-hydraulic jacks (EHA), injectors, ink jet printers, thrusters, dampers … A class of new electro-fluidic systems is emerging benefiting from the advantages provided by new smart actuators :
- Piezoelectric actuators : Piezo actuators, especially Amplified Piezoelectric Actuators (APA®) display relevant characteristics for pneumatic or hydraulic valves manufacturing: Fast response time; Proportional flow with DC voltage; Low electrical consumption; Mechanical integration outside or inside the fluid chamber. Because of their prestress, CEDRAT TECHNOLOGIES's actuators are suited to high bandwidth valves or injectors. Because the APA® are pulling piezo actuators, they naturally lead to normally closed piezovalves. Other fluidic applications are small oscillating pumps (piston or diaphragm types).
- Piezoelectric motors : Thanks to their blocking at rest and their long stroke (1 to 20mm), small piezo motors, such as the Stepping Piezo Actuators (SPA) are interesting candidates to design very low power consuming, micro or miniature precision valves (<1-5cm3) for dosing and embedded applications.
- Magnetic actuators : New magnetic actuators such as moving coils or controllable moving iron actuators (MICA) replace advantageously electromagnets in usual valves by offering much more controllability and by keeping voltage compatibility.
- Magnetostrictive actuators : Magnetostrictive actuators offer high forces at low voltage (12 or 24V), what meets special needs in biomedical, oil and chemical industries (because of ignition risks). : Magnetic actuators are the most usual components to build solenoid valves.
- Magnetorheological fluids : A magnetorheological fluid (MRF) can solidify when subjected to a magnetic field. This effect can be used to build valves without any moving parts, as well as semi-active fluid dampers, smart fluid bearings…
CEDRAT TECHNOLOGIES has developed or helped customers to develop new active valves and various electro-fluidic systems, using its broad experience in all these actuation techniques. Some examples are given hereafter or in our related publications on valves.