Patent attributes
A sectional drive and coupling system for transmitting rotational power to an output, which system includes multiple, splined drive and receiving segments that are connected, nested and interlocked in the ends of successive segment housings to define a drive string that is rotatable in a selected straight or curved path. The top one of the segments cooperates with a drive mechanism to effect rotation of the drive string in concert and the bottom one of the segments connects to an output such as a drill bit. Multiple, tapered and truncated exterior splines on the drive segments mesh with complementary interior splines on the adjacent receiving segments in the segment housings to enable slight angular positioning of the sets of drive and receiving segments on each other and facilitate dampening of drive vibration and bending of the drive string in or out of the chosen path in any desired direction as the drive string transmits rotational power in a curved path of desired magnitude from the drive mechanism to the output. The drive and receiving segments are typically connected internally by a bolt, nuts and belleville springs at the ends of the housings to form the drive string. In one embodiment a drill bit is mounted on the bottom one of the segments on the drive string for interval drilling. In another embodiment a selected number of drive and receiving segments and connected segment housings replace the flexible drive shaft coupling in a mud motor.
