Suspending the armature in this proportional, solenoid-controlled valve between two flexible Beryllium-copper springs eliminates metal-to-metal contact and sliding friction. The result is low hysteresis (1 to 3%) and long life.
The solenoid's low friction and light weight armature result in a frequency response of 250 Hz. The valve operates with 3% hysteresis on straight dc power, or a pulse width modulated (PWM) signal can reduce hysteresis to less than 1%.
Because a rolling diaphragm isolates the armature from the working fluid, the valve is suitable for both gasses and liquids.
Laura Vinson, Teknocraft Inc., (F) 425 West Dr., Melbourne, FL 32904; (407) 729-9634.