Abstract An adjustable high speed wood bit adapted for use with an electric drill and having a long cylindrical shank with a flat blade integrally formed on the lower end thereof. The flat blade has a point on its lower end for centering the drill and forming a pilot hole. The lower edges of the flat plate alongside of the point are oppositely sharpened to cut the wood in forming a bore. A pair of blades are pivotally secured to opposite sides of the flat plate with each blade having a slot partially overlying a vertical slot in the blade. A bolt extends through the three slots and may be raised and lowered in the vertical slot of the flat plate to cause the blades to swing outwardly increasing the diameter of the bit. The lower edges of the blades are sharpened to cut the wood in forming a bore. The bolt securely fastens the blades in adjusted position during the cutting operation. A scale is formed on the flat plate to cooperate with the side edge of one of the blades to indicate the size of the bore which will be drilled by the bit in a specific adjusted arrangement.
An adjustable high speed bit for electric drills comprising a generally cylindrical shank, a flat plate integrally secured to said shank and extending from the lower end thereof with spaced parallel side edges, a sharpened cutting edge formed on the lower edge of said plate, a cutting point integrally formed centrally of the lower edge of said plate symmetrical about the axis of said shank, a pair of cutter blades on opposite sides of said plate, said cutter blades having lower arcuate edges, a rivet pivotally securing the upper end portion of each of said blades to the upper end portion of said plate along the axis of said shank, means for adjustably securing said blades to said plate, and means including a scale on said plate for setting said blades for the desired circumference of cut.
Claim 2
Dependent Claim
137 words
An adjustable high speed bit for electric drills comprising a generally cylindrical shank, a flat plate integrally secured to said shank and extending from the lower end thereof with spaced parallel side edges, a sharpened cutting edge formed on the lower edge of said plate, a cutting point integrally formed centrally of the lower edge of said plate symmetrical about the axis of said shank, a pair of cutter blades on opposite sides of said plate, said cutter blades having lower arcuate edges, a rivet pivotally securing the upper end portion of each of said blades to the upper end portion of said plate along the axis of said shank, means for adjustably securing said blades to said plate, and means including a scale on said plate for setting said blades for the desired circumference of cut.
Claim 3
Dependent Claim
56 words
A device as claimed in claim 1, wherein the means for securing said blades in adjusted position on said plate includes a vertical slot extending through said plate along the axis of said shank, and a pair of angularly related slots and a clamping bolt extending through said slots for clamping said blades to said plate.
Claim 4
Dependent Claim
19 words
A device as claimed in claim 2, wherein said clamping bolt has a hand actuatable wing nut associated therewith.
Claim 5
Dependent Claim
22 words
A device as claimed in claim 1, wherein the lower arcuate edge of said cutting blades is sharpened to a cutting edge.