 What I claim is:
2. A chuck jaw having a longitudinal groove in the inner face thereof with a series of teeth at opposite sides of, and at one end of, said groove, another series of teeth at opposite sides of, and at the other end of, said groove, and an untoothed section separating said two series of teeth, said untoothed section bridging the weakest part of said jaw and being located in a plane below the tops of the teeth at each end thereof. 3. A chuck jaw having a longitudinal groove in the inner face thereof, with a series of teeth at opposite sides and at one end of said groove, another series of teeth at the opposite side of and at the other end of said aroove, and an untoothed section separating said two series of teeth, said longitudinal groove being deepest in the zone of said untoothed section, the surface of the untoothed section being in a plane substantially midway in the height of said teeth. CHARLES
E. MITCHELL.
|
This brace was made to a tight budget, because the handles are just black-painted hardwood. Except for the novel jaws, the rest of the brace's features are all from the public domain: ratchet, ball-bearing head, and wrist handle. Nevertheless, as-built, the brace was carefully and thoroughly lubricated. All I did when I cleaned it was wipe off the excess inside the chuck and on the patented jaws. The principal novel feature of the jaws is that they have no weakening teeth in the center of the unsupported span between the front and rear. The front of the jaws bears on the cone inside the shell; and the rear bears on another cone inside the cross slot in the spindle. When tightened excessively on an auger bit, lesser jaws tend to bend in the middle. I have seen plenty of hopelessly distorted "Barber's Improved" jaws, so the present patent would have been welcomed by Stanley's brace customers of the time. Except for showing a pair of jaws one tooth longer than the finished product, the inset patent drawing is faithful to the practice taught in the patent. |