Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
207 words
In a drilling head assembly for rotary well drilling, a vertically extending tubular member provided with an external screw thread adjacent to but spaced above its lower end, the outer surface of said member below said screw thread tapering downwardly to said lower end to form a sealing surface, a metal ring encircling said screw thread and sealing surface and provided with an internal screw thread engaging said first-mentioned thread for connecting the ring to said tubular member, the portion of said ring beside said sealing surface being spaced therefrom and extending downwardly below it and provided with an annular recess encircling and facing said surface, and a resilient sealing member encircling said ring and secured thereto with the portion of the ring beside said sealing surface and below it embedded in the sealing member, the sealing member filling said annular recess and converging downwardly below said ring to a neck portion of reduced diameter for fitting around a drill string, and the inner surface of the sealing member converging from above said annular recess downwardly to said neck portion, the sealing member being compressed between said tapered sealing surface and the encircling portion of said ring to form a seal between said tubular member and ring.
Claim 2
Dependent Claim
207 words
In a drilling head assembly for rotary well drilling, a vertically extending tubular member provided with an external screw thread adjacent to but spaced above its lower end, the outer surface of said member below said screw thread tapering downwardly to said lower end to form a sealing surface, a metal ring encircling said screw thread and sealing surface and provided with an internal screw thread engaging said first-mentioned thread for connecting the ring to said tubular member, the portion of said ring beside said sealing surface being spaced therefrom and extending downwardly below it and provided with an annular recess encircling and facing said surface, and a resilient sealing member encircling said ring and secured thereto with the portion of the ring beside said sealing surface and below it embedded in the sealing member, the sealing member filling said annular recess and converging downwardly below said ring to a neck portion of reduced diameter for fitting around a drill string, and the inner surface of the sealing member converging from above said annular recess downwardly to said neck portion, the sealing member being compressed between said tapered sealing surface and the encircling portion of said ring to form a seal between said tubular member and ring.
Claim 3
Dependent Claim
71 words
In a drilling head assembly according to claim 1, a flange encircling said ring and spaced therefrom, a plurality of circumferentially spaced spokes integrally connecting said ring and flange, at least one of said spokes having a lower extension provided with a passage therethrough extending radially of the ring, said passage being provided with a screw thread, and a set screw screwed into said passage and bearing against said tubular member.
Claim 4
Dependent Claim
29 words
In a drilling head assembly according to claim 2, the outer surface of said tubular member being provided with an annular groove receiving the inner end of said screw.
Claim 5
Dependent Claim
45 words
In a drilling head assembly according to claim 3, the height of said groove being substantially greater than the diameter of said screw therein to permit limited vertical adjustment of said tubular member in the ring while the set screw is projecting into the groove.