US Patent 7309086 Uni-knot tying apparatus

Disclosed is a uni-knot tying device. The device includes a stator, a hollow cylindrical rotor which is rotatably mounted on the stator, and a rotating drive operatively coupled to the rotor. The rotor has a proximal end and a distal end, and includes a longitudinal slot extending from the proximal end to the distal end. The device also includes a line locking member facing the proximal end of the rotor, as well as a tackle securing member and a line centering member facing the distal end of the rotor. Fishing line is threaded through the hollow cylindrical rotor and then looped around the same, forming a uni-knot.