Portable fan

A portable fan, comprising:

• a housing, comprising an accommodating cavity, wherein the housing is further formed with an air inlet communicated to the accommodating cavity;
• a substrate, wherein at least a portion of the substrate is arranged on a radial inner side of the housing;
• and
• a fan assembly, arranged inside the accommodating cavity and connected to a rear side of the substrate, wherein the fan assembly comprises a motor and a fan blade;
• wherein an air outlet is formed between a periphery of a maximum diameter of the substrate and the housing, and the maximum diameter of the substrate is greater than or equal to a maximum diameter of the fan assembly;
• a front side of the substrate comprises a protrusion;
• the protrusion protrudes forwards out of a front end of the housing and air flow blown out of the air outlet is guided by the maximum diameter of the substrate, thereby expanding a larger air blowing surface;
• and
• wherein a shaft tube is formed on the rear side of the substrate;
• a stator of the motor is arranged on an outer side of the shaft tube, a rotor of the motor is directly or indirectly fixed to the fan blade;
• and a rotating shaft of the motor is inserted into the shaft tube from back to front.