1. Field of the Invention
The present invention generally relates to clutching arrangements for positive feed drills and, in particular, to clutching arrangements for positive feed drills that feature two clutching gears mounted to separate shafts.
2. Description of the Related Art
Positive feed drills are used to produce accurately placed and accurately dimensioned holes in workpieces. One application of this type of drill is in the aircraft industry where the holes are formed in materials that can be very difficult to cut. In some environments, the drills may periodically bind during operation. The binding can result from overloading caused by drilling deep holes or by heavy reaming, which results in metal chips being packed heavily in between the cutter flutes. The torque and thrust loads can be very high under overload conditions, which may resist the automatic withdrawal of the cutter from the workpiece. With reference to FIG. 1, a prior construction of a positive feed drill will be discussed to illustrate some of the causes of the failures being experienced.
USPTO Backgrounds
USPTO Backgrounds