Threading device

A threading device configured to push a thread into a hole of a work piece, the threading device comprising:

• a thread-pushing rod having a first through hole defined therein,
• a thread-transmitting rod mounted on the thread-pushing rod and having a second through hole defined therein, the first through hole aligned with the second through hole,
• a first transmission subassembly and a second transmission subassembly both mounted on the thread-pushing rod, wherein the first transmission subassembly comprises:
• a first rotating member,
• a first spur gear mounted on the first rotating member;
• wherein the second transmission subassembly comprises:
• a second rotating member parallel with the first rotating member,
• a second spur gear mounted on the second rotating member and meshing with the first spur gear;
• wherein a passage is defined by the first rotating member and the second rotating member, the passage is configured to allow the thread to pass there through, and the passage is aligned with the first through hole and the second through hole,
• a first pushing member coupled to the first rotating member, the first pushing member configured to rotate the first rotating member, and further configured such that when the second spur gear and the second rotating member are rotated, the first rotating member and the second rotating member rotate in different directions, and at a contacting position of the first rotating member and the second rotating member, a tangent of a rotating direction of the first rotating member or a tangent of a rotating direction of the second rotating member are moved in a direction towards the thread-transmitting rod.