.[.The present invention discloses a.]. .Iadd.A .Iaddend.bidirectional mechanical converting unit.[., comprising.]. .Iadd.includes.Iaddend.: a main shaft; a driving mechanism, which including a driving .[.means.]. .Iadd.assembly .Iaddend.and a reversing .[.means.]. .Iadd.assembly .Iaddend.which are coupled to each other; and a rotation .[.means.]. .Iadd.assembly .Iaddend.for inputting torque, an rotation axis of the rotation .[.means.]. .Iadd.assembly .Iaddend.being coaxial with the main shaft, the rotation .[.means.]. .Iadd.assembly .Iaddend.and the driving mechanism being coupled to each other, and the driving mechanism delivering the torque to output at the main shaft at a predetermined direction, no matter in which direction the rotation .[.means.]. .Iadd.assembly .Iaddend.rotates; wherein the predetermined direction can be switched via the reversing .[.means.]. .Iadd.assembly.Iaddend.. .[.The present invention is simple structured, not only can efficiently utilizes the movements of the rotation means in either way, but also can switch the rotation direction of the output shaft conveniently upon demand, with easy operations..].

The present invention is a continuous medical instrument adapter that safely provides a 180-degree torque force during a surgical procedure while accommodating the range of motion of the surgeon's hand during the surgical procedure. The drive mechanism of said adapter is capable of non-lubricated function, enabling it to be used in a medical environment and to be sterilized without loss of function.