| Abstract: | A fluid-powered linear motor with rotary pistons is disclosed. An
application is for a downhole motor but it could be used in other
applications. Rotational pistons provide increased torque generation as
the torque generated is proportional to motor length. Since downhole
drills are long (generally up to a maximum length of 30 ft.), a
high-torque motor can be produced using this method. A pressurized fluid
is used to drive the piston assemblies to produce bit shaft power. This
concept employs rotary pistons and a mechanical rectifier to convert the
rotational reciprocation produced by a reciprocating rotational piston
into continuous rotary motion. Integration of synthetic diamond bearing
assemblies into the motor allows for reduced friction and abrasive
drilling fluid compatibility. |