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.