PROPELLER SHAFT OF HYDRAULIC DOWNHOLE MOTOR Russian patent published in 2016 - IPC E21B4/02 F16C1/02 

FIELD: machine building.

SUBSTANCE: invention relates to drives of rotation arranged in a well, in particular arranged inside screw gerotor hydraulic motor. Propeller shaft comprises a shaft with longitudinal axis and two half-couplings. Each half-coupling covers one of edges of shaft. Between each half-coupling and corresponding edge of shaft there is a row of drive mechanisms to transmit torque and mutual angular displacement, including made on edges of shaft rows of grooves, radially directed outward. Each groove has base surface in plane along longitudinal axis of shaft. In half-coupling there is a peripheral surface, receiving a drive mechanism, including protrusions arranged at edges of shaft, segment supports with flat side surface, movably in contact with side surfaces of grooves made in half-coupling, and opposite curved side surfaces of segment supports, movably connected with corresponding bent surfaces of protrusions arranged at edges of shaft. Between ends of shaft and each half-coupling there is a thrust and a thrust bearing. On each edge of shaft there are three arranged along a circle segment recess on base surface of shaft. Each segment recess is made with flat bottom surface. Bottom of every segment recess is located parallel to longitudinal axis of shaft. Each segment support is installed in segment recess with circumferential side clearance, maximum value of which is equal to gap between inner peripheral surface of half-couplings and base surface of grooves on edge of shaft, arranged along longitudinal axis of shaft. Each base surface on each edge of shaft has a first pair of flat surfaces converging at an angle relative to bottom of segment recess. Outer surface at each edge of shaft crossing curved surface segment of recess at edge of shaft, comprises cylindrical belt, coaxially located relative to longitudinal axis of shaft, and second pair of conical surfaces, converging at an angle to cylindrical zone between them. External surface of each segment support, covered by half-coupling has its own cylindrical belt, coaxially located relative to longitudinal axis of shaft, and third pair of conical surfaces covered by half-coupling and converging at an angle to its own cylindrical zone between them.

EFFECT: longer service life and reliability, increasing transmitted torque.

3 cl, 8 dwg, 1 tbl