Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
133 words
A rotary drill bit, adapted for connection with a drill column, for drilling large diameter shafts in the earth comprising; a main bit body having a face across which drilling fluid is adapted to flow and a central opening adapted for communication with the interior of the drill column for enabling drilling fluid to pass therethrough; a plurality of cutters mounted on the face of said main bit body forming a cutting plane for contacting and disintegrating the earth formation at the shaft bottom; and means radially positioned on the face of said main bit body for enhancing the flow of drilling fluid across the face of said main bit body, said flow enhancing means includes an axial flow impeller rotating about an axis positioned on the radius of said main bit body.
Claim 2
Dependent Claim
133 words
A rotary drill bit, adapted for connection with a drill column, for drilling large diameter shafts in the earth comprising; a main bit body having a face across which drilling fluid is adapted to flow and a central opening adapted for communication with the interior of the drill column for enabling drilling fluid to pass therethrough; a plurality of cutters mounted on the face of said main bit body forming a cutting plane for contacting and disintegrating the earth formation at the shaft bottom; and means radially positioned on the face of said main bit body for enhancing the flow of drilling fluid across the face of said main bit body, said flow enhancing means includes an axial flow impeller rotating about an axis positioned on the radius of said main bit body.
Claim 3
Dependent Claim
49 words
The combination of claim 1 further including a wall portion attached to the main bit body face adjacent said flow enhancing means on the trailing side thereof, said wall portion extending to the cutting plane for forming a channel for the fluid flow passing through said flow enhancing means.
Claim 4
Dependent Claim
16 words
The combination of claim 2 further including drive means for rotatively driving said axial flow impeller.
Claim 5
Dependent Claim
55 words
The combination of claim 3 wherein said axial flow impeller is mounted on a shaft and said drive means includes a drive wheel secured on said shaft, the periphery of said drive wheel extending to said cutting plane in order to contact the surface of the shaft bottom and have a rotary motion imparted thereto.
Claim 6
Dependent Claim
19 words
The combination of claim 4 wherein said drive wheel is mounted adjacent the periphery of said main bit body.
Claim 7
Dependent Claim
31 words
The combination of claim 2 further comprising a skirt attached to the main bit body face at least partially about the circumference of the central opening of the main bit body.
Claim 8
Dependent Claim
15 words
The combination of claim 2 wherein said wall portion is made of a flexible material.
Claim 9
Dependent Claim
18 words
The combination of claim 1 wherein said axial flow impeller comprises a helical brush mounted on a shaft.
Claim 10
Dependent Claim
30 words
The combination of claim 8 wherein the outer edges of said helical brush bristles extend beyond the cutting plane of the cutters to contact the surface of the shaft bottom.
Claim 11
Dependent Claim
16 words
The combination of claim 8 wherein said brush bristles are made of a synthetic flexible material.
Claim 12
Dependent Claim
18 words
The combination of claim 1 wherein said axial flow impeller comprises a screw conveyor mounted on a shaft.
Claim 13
Dependent Claim
32 words
The combination of claim 11 wherein the outer edges of said screw conveyor extend within the cutting plane of the cutters to provide a clearance with the surface of the shaft bottom.
Claim 14
Dependent Claim
33 words
The combination of claim 1 wherein said axial flow impeller comprises a screw conveyor mounted on a shaft and a quantity of brush bristles attached to the outer edges of said screw conveyor.
Claim 15
Dependent Claim
25 words
The combination of claim 13 wherein said brush bristles extend beyond the cutting plane of said cutters to contact the surface of the shaft bottom.
Claim 16
Dependent Claim
29 words
The combination of claim 1 wherein said axial flow impeller comprises a plurality of paddle-blades mounted on a shaft, each paddle-blade being pitched to provide for an axial flow.