Drill for Making Square Holes (Patent No: 212018)
Inventor: Bridarolli, Valentine
Description: Valentine Bridarolli, Calgary, Alberta, Canada, 31st May, 1921: 6 years. Filed 12th June, 1919. Receipt No.311,029.
Claim.—A square hole drill consisting of a three-bladed member provided with flat cutting edges radiating from a centre, the said cutting edges adapted to plane the material to be drilled within a guide, the guide edges designed to act as an oscillatory medium, the perpendicular edges of the said cutting edges acting as reamers and a means of revolving the said, drill within the guide, all substantially as described.
Claim allowed, 1.