Abstract: A fluid-driven alternator for use in a downhole well bore having fluid flowing therethrough includes a housing and an internal impeller rotatably mounted in the housing. A stator and rotor are mounted within the housing, and the internal impeller is coupled to the rotor. Fluid flowing through the housing rotates the impeller which in turn rotates the rotor. A flow diverter can be provided to direct fluid into the housing.

Abstract: A fluid-driven alternator for use in a downhole well bore having fluid flowing therethrough includes a housing and an internal impeller rotatably mounted in the housing. A stator and rotor are mounted within the housing, and the internal impeller is coupled to the rotor. Fluid flowing through the housing rotates the impeller which in turn rotates the rotor. A flow diverter can be provided to direct fluid into the housing.

Abstract: For the directional drilling of boreholes, the orientation of accelerometer modules, magnetometer modules and gyroscopes or other directional sensing devices must be accurately known and maintained with respect to each other and to external mounting devices. This is accomplished by a self-aligning segmented cylindrical connection which accurately maintains modules in rotational alignment with each other for all three directions of rotation, even if the mating surfaces of the connection experience wear due to rough use in the drilling application or repeated calibration in a calibration fixture. Wedged surfaces on each of the male and female portions of the connection constitute the mating surfaces, and are the only surfaces at which the male and female portions contact one another. A depression between the mating surfaces defined by the female portion permits reproducible angular displacement of one portion with respect to the other even if one or both portions are worn.