The power takeoff drive is provided through the second bevel
gear (19) located within the accessory gear carrier, and it is used
to drive airframe accessories.
The N2driven overspeed governor and tachometer drive gearbox
(1) receives its drive from a spur gear (20) pressed to the power
shaft aft of the sun gear. This gear engages the N2 drive and driven
gear package (8) located within the accessory gear carrier. This
package, a series of three gears, provides an internally splined
drive for the drive shaft (2) which passes up through the ten o'clock
inlet housing strut and into the gearbox (1).
The drive shaft then engages the internal splines of the upper
drive gear (3) which provides drive to the tachometer gear (5). This
gear meshes directly with an idler gear (6) which in turn transmits
the drive to the combination torquemeter boost pump and overspeed
governor drive gear (7).
is mounted on the underside of the engine inlet housing and is driven
Drive pads are provided on rear of the gearbox for the fuel control,
the startergenerator, and the gas producer (N1) tachometer generator.
The gearbox front side has mounting for the rotary oil pump, and also
has an unused drive pad with connection for the torquemeter pressure
transmitter vent line. Oil scavenge lines are connected at right
rear on the gearbox which is an oil collector sump, kept practically
empty by the pump. A chip detector plug is located in the lower
right side, and the oil filter is on the left side.
in figure 4.11, is a gearbox mounted on the engine inlet housing at
the upper left side and is driven from the power shaft. The drive
assembly provides mounting and drive pads for the power turbine (N2)
T53L701) and also drives the fuel control overspeed governor. A
relief valve, on the drive housing, allows adjustment of torquemeter
oil pressure. An internal filter and metering cartridge lubricates
the gear train.