FLEXIBLE SHAFT Russian patent published in 2009 - IPC F16C1/02 F16C3/02 

FIELD: mechanical engineering.

SUBSTANCE: flexible shaft can be used in devices for cased well perforation when torque moment and axial force are transferred from hydraulic downhole motor (driving link) to cutter head (16) (driven link). Torque moment is transferred via end elements (2, 3) and flexible part (1). Axial force is transferred via cylindrical rings (4, 5, 6) mounted on the flexible part (1) between end elements (2, 3). Cylindrical rings (4, 5, 6) create rigid connection of end elements (2, 3) and provide axial force transfer to cutting head (16) bypassing flexible part (1), thereof flexible shaft gets increased axial rigidity.

EFFECT: providing axial force transfer to cutting head (16) bypassing flexible part thereby increasing axial rigidity to flexible shaft.

2 cl, 2 dwg