Drill and reamer for composite material
AssigneeStorage Technology Corporation
InventorLarry G. Adams
Life of this patent
Estimating the term…
Abstract
A diamond coated drill bit capable of drilling small holes and then reaming the holes to their correct size. The tapered tip of the drill bit has a coarse diamond grit coating which enables it to initiate a hole. The drill bit then gradually grinds the hole to the proper size with a grinder having coarse diamond grit bonded to its surface which is at a predetermined taper. The final diameter of the hole is controlled by using a fine grit diamond reamer above the tapered grinder portion. The grinder applies a radial load to the composite material resulting in no fiber breakout or splintering. The tapered grinder and the reamer are formed on a machined-flat portion of the drill bit which enables coolant to circulate down to the grinding area and allows the easy removal of debris.
Claims13
A drill bit, having a first end and second end, for creating a hole in a composite material, the drill bit comprising:
- a tip at said first end;
- a shank portion at said second end;
- a grinder adjacent to said tip, for initiating the hole, said grinder portion having a substantially rectangular cross-section with substantially cylindrical surfaces on one pair of opposite sides, said substantially cylindrical surfaces of said grinder portion axially tapering towards said tip, said grinder portion having a grinding means on said substantially cylindrical surfaces;
- and
- a reamer portion disposed between said grinder portion and said shank portion, for finishing said initiated hole, said reamer portion having a substantially rectangular cross section with substantially cylindrical surfaces of substantially constant diameter on one pair of opposite sides, said reamer portion having a reaming means on said substantially cylindrical surface.
A drill bit, having a first end and second end, for creating a hole in a composite material, the drill bit comprising:
- a tip at said first end;
- a shank portion at said second end;
- a grinder portion adjacent to said tip, for initiating the hole, said grinder portion having a substantially rectangular cross section with substantially cylindrical surfaces on one pair of opposite sides, said substantially cylindrical surface of said grinder portion axially tapering towards said tip;
- a reamer portion disposed between said grinder portion and said shank portion, for finishing said initiated hole, said reamer portion having a substantially rectangular cross-section with substantially cylindrical surfaces of substantially constant diameter on one pair of opposite sides;
- and
- a clearance area disposed between said shank portion and said reamer portion, having a substantially cylindrical cross-section with a diameter which is less than said substantially constant diameter of said substantially cylindrical surfaces on said first pair of opposite sides of said reamer portion,
- wherein said reamer portion has substantially flat surfaces on a second pair of opposite sides of said rectangular cross section of said reamer portion, the distance between said substantially flat surfaces being is less than said substantially constant diameter of said cylindrical surfaces of said reamer portion, and
- wherein said grinder portion has substantially flat surfaces on a second pair of opposite sides of said rectangular cross section of said grinder portion.
Dependencies are inferred from the claim text.