THE TONE WHEELS
The main generator is a long structure in which are mounted 48 rotating assemblies, each
consisting of a shaft and two discs known as tone or phonic wheels. These assemblies are coupled
resiliently to the drive shaft. Each of the driving gears engages two bakelite gears associated with
rotating assemblies on opposite sides (See Figure 11).
These bakelite gears rotate freely on the shafts with the tone wheels, and are coupled to their
respective assemblies by a pair of coil springs. There are 12 sizes of bakelite gears, corresponding
to the 12 sizes of driving gears. Thus 4 of the tone wheel assemlies, each with 2 tone wheels, run
at each of 12 speeds.
Each tone wheel is a steel disc about 2 inches in diameter, accurately machined with a definite
number of high and low points on its edge (See Figure 10).
Each high point on a tone wheel is called a tooth. The number of teeth on each of these tone or
phonic wheels, in conjunction with the speed at which the tone wheel is revolving, determines the
frequency of the tone generated.
Each driving gear, with its two bakelite gears and four tone wheels, runs in a separate
compartment magnetically shielded from the rest by steel plates which divide the generator into a
series of bins.
All four tone wheels in any one compartment run at the same speed. The individual tone wheel
shafts are mounted in bearings made of a special porous bronze and each of these bearings is
connected to the oiling system by a cotton thread from the oil trough. Thus, oil from the trough is
carried by capillary action to all bearings, penetrating them and lubricating the actual bearing
surface. The drive shaft and both motors are lubricated in a similar manner. It is very important to
use the recommended grade of oil, as it is essential to the proper operation of the organ that the
generator be well lubricated. If oil of other grades is used, it is likely the the generator may be
sluggish in starting, and in time the threads may gum up and prevent the proper flow of oil. Follow
oiling instructions within the console.
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