Abstract: A pivotable connecting device adapted to transmit rotary motion from a drive member to a driven member while minimizing the effect of torque thereon. The drive member is provided with a fork having first and second shanks each with a threaded hole. The driven member is provided with a coupling plate having a corresponding smooth hole. A screw member for insertion in the holes is provided having a smooth central portion and first and second threaded ends. The diameter of the first threaded shank hole is greater than that of the coupling plate smooth hole, and the diameter of the latter is at least as great as the diameter of the second threaded shank hole. The pitch and helix of the first and second threaded shank holes are identical thereby permitting simultaneous tightening of the first and second threaded screw ends into the corresponding first and second threaded shank holes.