Winding mechanism and lamp

A winding mechanism, comprising:

• a housing formed with an accommodating space therein, wherein an inner surface of the housing is formed with an internal thread structure;
• an inner cylinder disposed in the accommodating space, wherein the inner cylinder defines a central axis, an outer surface of the inner cylinder is formed with an external thread structure, the external thread structure is cooperated with the internal thread structure, the inner cylinder is capable of displacing along the central axis by rotating relative to the housing, the external thread structure comprises at least two contact portions and at least two non-contact portions, and gaps are formed between the non-contact portions of the external thread structure and the internal thread structure;
• and
• a wire, wherein an end of the wire is connected to the inner cylinder and is wound along the external thread structure of the inner cylinder, and as the inner cylinder is displaced along the central axis by rotating relative to the housing, a portion of the wire is capable of being wound around or separated from the external thread structure of the inner cylinder.