BLOWER DRIVE MECHANISM
7-20. The power to drive the blower is transmitted from the upper crankshaft through a gear train. The train
consists of a drive gear, a pinion gear, and the two timing (impeller) gears of the blower.
Flexible Drive Gear
7-21. The principal parts of the flexible drive gear are a spider drive hub which is keyed to the crankshaft, a
gear within which spring spacers are bolted, and springs which absorb torsional oscillations transmitted by the
crankshaft. A view of the flexible drive gear, with end plate removed, is shown in Figure 7-7.
Drive Pinion
7-22. The flexible drive gear meshes with the drive pinion. The pinion is keyed to the lower impeller shaft
and is held in place by a locknut. The lower impeller driving (timing) gear meshes with the upper impeller
driving gear.