Patent attributes
A fastening device includes a case unit, a knob, an engaging unit and a spool. The case unit has an axial direction and includes a plurality of mounting teeth. The knob covers on the case unit along the axial direction. The engaging unit is coupled to the knob and includes an engaging portion. The spool is configured for a lace to wind therearound. The engaging unit is driven by the knob to switch between a first position and a second position along the axial direction. When the engaging unit is in the first position, the engaging unit prohibits the spool from releasing the lace. When the engaging unit is in the second position, the engaging portion is engaged with at least one of the mounting teeth, and the engaging unit does not prohibit the spool from releasing the lace. Therefore, the reliability can be improved.