An electrically actuated aircraft brake system and method which provides
for brake wear measurement, brake running clearance adjustment, ram
position-based control and improved construction and operation. Brake
wear and running clearance measurement are obtained by analyzing the
output of position sensing circuitry. The position sensing circuitry,
preferably including a LVDT position sensor, is also used to determine
braking load, a brake controller including circuitry for effecting
displacement of one or more reciprocating rams to load a brake disk stack
by a predetermined amount based on a present displacement value of the
position signal obtained from the position sensor. The position sensor
preferably includes a LVDT transducer connected between the reciprocating
ram and a brake housing, and the motive device preferably includes a
servo motor. Also provided is an actuator housing including a guideway
for each ram, the guideway and ram having the same polygonal
cross-section, whereby the ram nut is guided and restrained from rotation
by the guideway as it is translated by a ball screw in threaded
engagement with the ram nut for selective movement into and out of
forceful engagement with the brake disk stack for applying and releasing
braking force on a rotatable wheel. An electric motor is drivingly
connected to each ball screw by a first gear integral with the ball
screw, a second gear in mesh with the first gear, and a pinion on a
rotating drive shaft of the electric motor.