Abstract: A fan guard has a function of supercharging a fan in addition to supporting a rotor device is disclosed. The fan guard is to be mounted beside the rotor device for supporting the rotor device, and additionally, the fan guard interacts with an airflow generated by the revolution of the rotor blades to supercharge the fan. The fan guard essentially includes a main frame, and a set of guard blades radially arranged inside the main frame and fixed onto an inner surface of the main frame by each one end thereof. Each of the guard blades is preferred to have a shape similar to the shape of the rotor blades, and the set of guard blades can be arranged either upstream or downstream of the rotor blades.

Abstract: A driven unit driven adapted to be used in a cross fan is provided. The driven unit is driven by a motor. The main feature of the driven unit is that there is a concave region on the surface of its rotary shaft. The elastic rubber cap is embedded in the concave region and the embedded portion of the rubber cap can tightly connect the rotary shaft with the rubber cap. Therefore, the blades sleeved on the rotary shaft can be fixed in the right position without shifting. The cross fan having the driven unit of the present invention will have a relatively longer useful life.