Direct drive servo valve.

摘要

A direct drive servo valve includes a valve housing (10) having a cylindrical bore (12) and a valve spool (28) mounted for movement in the bore for controlling fluid flow through said valve housing. The valve spool has a drive well (30) located in the spool transverse of its longitudinal axis. A motor secured to the valve housing includes a rotor (48) which is rotated in response to a drive signal applied to stator windings (46) of the motor. A shaft (50) attached to the rotor for rotation therewith includes a substantially spherical drive tip (76), the spherical tip positioned eccentrically to the longitudinal axis of the shaft and being close fitted into the drive well (30). In operation, as the shaft rotates through a given angular rotation, the spherical tip rotates in a circular path to provide linear displacement and rotational motion to the valve spool.