Patent ID: 8365843

Claim:
A downhole drill string component, comprising: a connection for attaching said drill string component to an adjacent drill string component; a bore in said drill string component for receiving drilling mud; a turbine disposed within said bore configured to be rotated by drilling mud passing through said bore; a centrifugal clutch that includes a gripper attached to a spring, said centrifugal clutch being connected to said turbine and operable by the rate of rotation of said turbine between an engaged position and a disengaged position; and, a linear actuator aligned with a central axis of said drill string component, said linear actuator being coupled to said centrifugal clutch when said centrifugal clutch is in said engaged position and decoupled from said centrifugal clutch when said clutch is in said disengaged position, said linear actuator including: a driving gear; a cam; and, a switch plate coupled to said driving gear, said switch plate configured to move when said cam rotates and thereby causing said driving gear to selectively engage a plurality of gears mechanically connected to said driving gear, said plurality of gears configured to convert said rotation of said turbine into an axial motion in a direction parallel to said central axis.