Patent ID: 8544560

Claim:
A drive mechanism for use on a pipe or drillstring comprising: a driving member configured in use to be disposed around the pipe or drillstring, the driving member comprising a plurality of drivers linearly translatable with respect to the driving member and in a longitudinal direction with respect to a center axis of the pipe or drillstring, each of the drivers having at their ends a male engaging portion; and an associated driven member configured in use to be disposed around the pipe or drillstring, the driven member comprising a plurality of female receiving portions each adapted to receive a one of the male engaging portions, wherein; the male engaging portion comprises a v-shape projection comprising a first and a second inclined engaging surface, the first and the second inclined engaging surfaces meeting to form a tip of the v-shape projection; the female receiving portion comprises a v-shape indentation comprising a first and a second inclined receiving surface, the first and the second inclined receiving surfaces meeting to form a bottom of the v-shape indentation; in use the plurality of drivers and the driven member are configured such that a linear translation of a first of the plurality of drivers causes the male engaging portion of the first of the plurality of drivers to engage with a first of the female receiving portions and the engagement of the male engaging portion of the first of the plurality of drivers with the first of the female receiving portions causes a reaction in the first of the female receiving portions producing a displacement of the driven member in a direction other than that of the translatable driver; the displacement of the driven member causes the driving member and the driven member to be configured such that a second of the plurality of drivers is positioned to be engagable with a second of the plurality of female receiving portions such that engagement of the second of the plurality of drivers with the second of the plurality of receiving portions causes a further displacement of the driven member; and wherein the linearly translatable drivers are elongate and arranged to be moveable in a direction parallel to their length, and wherein the plurality of drivers and the plurality of female receiving portions are configured such that engagement of the first of the inclined engaging surfaces with a first of the inclined receiving surfaces produces the displacement of the driven member in the direction and engagement of the second of the inclined engaging surfaces with a second of the inclined receiving surfaces produces the displacement of the driven member in a reverse direction.