Feed oscillation via variable pitch gears

A positive feed tool comprising:

• a motor;
• a power supply operably coupled to the motor to power the motor;
• a gear head operably coupled to the motor to be operated responsive to powering of the motor, the gear head comprising a drive assembly and a feed assembly;
• and
• a spindle operably coupled to the gear head to enable the spindle to be selectively driven rotationally and fed axially based on operation of the drive assembly and the feed assembly, respectively;
• wherein the feed assembly comprises a feed rate oscillator comprising a spindle feed gear coupled to a differential feed gear, the spindle feed gear being carried on the spindle to rotate the spindle to selectively axially feed the spindle, the differential feed gear being carried on a feed shaft and being selectively operably coupled to an input shaft turned by the motor;
• wherein at least one of the spindle feed gear or the differential feed gear is a variable pitch diameter gear having a variable pitch diameter;
• wherein the variable pitch diameter gear includes an oscillating gear tooth profile to provide the variable pitch diameter, the oscillating gear tooth profile comprising a plurality of regions, each region having a first tooth density, a second tooth density, or a third tooth density and the regions being disposed around a periphery of the variable pitch diameter gear in accordance with a tooth density pattern, wherein the first tooth density is greater than the second tooth density and the second tooth density is greater than the third tooth density, and
• wherein the tooth density pattern defines a repeating sequence of adjacent regions having the second tooth density adjacent to the first tooth density adjacent to the second tooth density adjacent to the third tooth density.