Magnet moves ball for fast response

Problem: Designers of valves, especially for use in aerospace, constantly search for lowest possible weight, fast response, and maximum reliability. Conventional spool valves have potential drawbacks in all three of these categories. Solution: Seeking a better valve for satellite steering jets, DLR, or the Deutsches Zentrum fur Luft und Raumfahrt, has come up with a ball valve which performs brilliantly in all three departments. The inventors, DLR's Dr Dietmar Neuhaus, explained to Eureka that the ball sits in a space between two plates within a solenoid coil. In normal use, the passage of fluid through the valve presses the ball onto its valve seat, closing the valve. The coil is constructed with a gap in its ferromagnetic enclosure adjacent to the ball. This causes magnetic flux to leak out close to the ball when the coil is energised. Under such circumstances, the ball is attracted to one side of the space and rolls off its seat, allowing fluid to pass. It is advantageous to make the balls light in weight. Hollow balls made of ferromagnetic material with suitable protective coatings are recommended. Because there are no springs and the valve element rolls instead of sliding, wear can be expected to be very low. Applications: Prototypes of the valve have been developed for service with different gases and liquids. Valves have been developed for applications that include the dosage of adhesives and printing inks. The concept is considered to be useful in a multitude of hydraulic, chemical and pneumatic applications including sorting equipment. The technology has been licensed to GSR Ventiltechnik in Vlotho near Bielefeld. TS GSR Ventiltechnik