Hamilton Sundstrand Company ACT2000 - Manual (Page 32)

26 ACT2000 USER GUIDE
Resolver Assembly
A brushless, non-contacting resolver is the primary ACT2000 feedback
sensor. Resolver excitation is achieved via a sinusoidal signal from the
MCE. The resolver provides two sinusoidal feedback signals back to the
MCE. The resolver assembly includes a stator and rotor. See Figures 2-2
and 2-3.
Resolver Stator
The resolver stator is clamped to the main housing between the main
bearing retaining nut and resolver retainer. The angular position of the
resolver stator relative to the resolver rotor is adjustable. Electrical wires
from the resolver are reeled in the resolver adapter to allow rotation. The
resolver wires, along with the motor and thermistor leads, are routed
through a conduit into the electronics housing.
Resolver Rotor
The resolver rotor is mounted to the ball screw shaft by a key. As the rotor
rotates, the stator transformer output signals provide shaft rotation
information to the MCE.
Linear Drive Mechanism
The Linear Drive Mechanism converts the rotary motion of the Motor
Assembly to linear actuator motion. The core of the mechanical drive
system is the linear ball screw drive containing a screw shaft, ball-
bearing-fitted nut, extension rod and main duplex thrust bearings.
Screw Shaft
The thrust bearings, motor rotor, motor end bearing, and resolver rotor
are mounted directly to the screw shaft. A ball-bearing track is machined
into the screw shaft.
Ball Nut
As the screw shaft rotates, the ball nut translates the rotary motion into
linear motion along the shaft axis. The direction of movement along the
shaft axis is determined by direction of rotation.
Extension Rod and Bearings
The extension rod is threaded on the ball nut. As the ball nut translates,
the extension rod moves in and out of the ACT2000 main housing.
Counter-clockwise (CCW) rotation (facing the motor end of the actuator)
of the motor rotor and screw shaft results in the extension rod extending
out of the main housing. Clockwise (CW) rotation results in the extension
rod retracting back into the main housing.
The extension rod support bearing is provided for lateral support. Thrust
and radial loads are transferred from the extension rod through the ball