Patent ID: 6923212
Filing Date: 2005-08-02
Classification: F15B,F16K,Y10T

Abstract:
1. A servovalve system for regulating fluid flowing within a fluid circuit, the servovalve system including a fail safe apparatus adapted for switching the servovalve system between an operating position and a fail safe position, the servovalve system comprising: a housing having a housing bore and a housing chamber; an elongate spool axially moveably disposed within the housing bore; a stepper motor operatively connected to the spool and configured to be rotatable over a desired angle of rotation in order to selectively vary a spool position relative to the housing bore for manipulating the fluid flowing within the fluid circuit when the servovalve system is in the operating position; a rotary-linear converter interposed between the stepper motor and the spool and configured to convert rotational motion of the stepper motor into axial motion of the spool; and a piston axially moveably sealed within the housing chamber, the piston being mechanically coupled to the rotary-linear converter and being operative to move the spool from the operating position to the fail safe position upon a loss of fluid pressure in the housing chamber.