Tuning machine for stringed instruments

A tuning machine for a stringed instrument comprising:

• an input shaft having a first end, and an opposite second end having an eccentric with a centre offset from a central axis of the input shaft, the input shaft being rotatable in response to an input from a user;
• a gear member with a central axial bore to receive the eccentric to move the gear member though an eccentric circular motion as the input shaft rotates, the gear member having external teeth;
• a ring gear having internal teeth positioned around the external teeth of the gear member, the ring gear being larger than the gear member to accommodate the eccentric circular motion of the gear member within the ring gear such that at least one of the external teeth meshes with and drives at least one of the internal teeth as the gear member moves through its eccentric circular motion to rotate the ring gear about its central axis;
• and
• a string post driven by the ring gear to wind a string of the instrument as a result of rotation of the input shaft in one direction and unwind the string as a result of rotation of the input shaft in an opposite direction.