DOCUMENT # 90021, REV 4 MODEL 7000 GYRO OPERATION MANUAL-MAR09
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1.1
GYRO ASSEMBLY
The gyro assembly consists of a flywheel housed in a cast aluminum vacuum-tight sphere. The
flywheel spins about a vertical axis and is supported by upper and lower pairs of bearings. A DC
brushless motor mounted inside the enclosure spins the flywheel at high speed.
The enclosure is fastened to two gimbal shafts that are supported by gimbal bearings on either
side. These shafts establish an athwartship gimbal axis about which the flywheel and enclosure
precess or rotate up to +/- 60 degrees during operation. Each of the gimbal bearings is supported
by a saddle beam which is bonded to the hull structure. These beams transfer the loads that the
gyro produces to the hull structure.
An active hydraulic brake mechanism is located on gyro assembly to regulate the gyro’s
precession motions about the gimbal shaft. It includes two hydraulic cylinders mounted on the
port saddle beam and a hydraulic manifold on the starboard saddle beam.
A coolant pump, heat exchanger, accumulator, and thermostatic mixing valve are located on a
cross brace at the back of the gyro that connects the port and starboard saddle beams. A
glycol/water mix is circulated thru a closed loop to the end caps of the spherical enclosure,
hydraulic manifold and motor drive box to remove heat.
