| 摘要 |
<p>An apparatus for selectively controlling the direction of a well bore comprising a mandrel (11) rotatable about a rotation axis; a direction controller means comprising at least two parts (12) configured to apply a force to said mandrel (11) with a component perpendicular to the said rotation axis; a housing (13) having an eccentric longitudinal bore forming a weighted side (20) and being configured to freely rotate under gravity; and a driver for selectively varying the angle of the force relative to the weighted side (20) of the housing (13) about said rotation axis, the driver being configured to move the two parts independently of one another.</p> |
