Propeller mechanical pitch stop lock and low pitch stop assembly

Claim 1

IN A VARIABLE PITCH PROPELLER HAVING A HUB WITH A PLURALITY OF PROPELLER BLADES JOURNALLED THEREIN FOR ROTATION ABOUT THEIR LONGITUDINAL AXES AND PITCH CHANGING MEANS OPERATIVELY CONNECTED TO THE BLADES FOR VARYING THE PITCH POSITION THEREOF, MECHANICAL STOP MEANS OPERATIVELY ENGAGEABLE WITH SAID BLADES AT A PREDETERMINED PITCH POSITION THEREOF FOR PREVENTING PITCH CHANGING MOVEMENT IN A DECREASE PITCH DIRECTION, MECHANICAL LOCK MEANS OPERATIVELY ENGAGEABLE WITH SAID BLADES FOR PREVENTING PITCH CHANGING MOVEMENT THEREOF IN THE DECREASE PITCH DIRECTION, AND SINGLE SERVO MEANS RESPONSIVE TO FLUID UNDER DIFFERENT PRESSURES FOR SELECTIVELY RELEASING THE LOCK MEANS ALONE OR BOTH THE LOCK MEANS AND THE STOP MEANS.