When the fan is working, the airflow enters the blade space from the axial direction of the fan, and then rotates with the impeller under the drive of the impeller; on the other hand, it increases energy under the action of inertia and leaves the impeller along the radial direction. Fans that work by generating centrifugal force are called centrifugal fans. The transmission mode of the centrifugal fan, the transmission mode has the following six regulations. 

 

The detailed analysis is as follows: 

Type A: cantilever type, no bearing, the impeller of the boiler centrifugal fan is directly installed on the motor shaft, and the speed of the boiler centrifugal fan is the same as that of the motor. It is suitable for small fans with a compact structure and petite body. 

Type B: cantilever type, with transmission structure, and the pulley is installed between two bearing housings. Suitable for medium and larger fans with variable speed. 

Type C: cantilever type, belt transmission structure, the pulley is installed on the outside of the two bearing housings. It is suitable for medium-sized and above centrifugal boiler fans with variable speeds, and the belt wheels easily disassemble. 

Type D: cantilever type, the transmission structure connecting the fan and the motor shaft, the coupling is installed on the outside of the two bearing seats, and the fan speed is the same as the motor. Suitable for medium-sized boiler centrifugal fans. 

Type E: belt drive structure, two support bearings are installed on both sides of the housing, that is, the impeller is placed in the middle of the two support bearings, which is a double support, and the pulley is installed on one side of the centrifugal fan. Suitable for double suction or large single suction, the speed of the centrifugal fan is variable, and it has the advantage of running balance. 

Type F: The transmission structure of the boiler fan and the motor shaft.