Abrasive belt polishing machine

The utility model discloses an abrasive belt polishing machine. The abrasive belt polishing machine comprises a PLC system, a servo proportional valve, a pressure air cylinder, swing arms, a supporting arm, a polishing wheel, an expansion wheel and a driving mechanism. The PLC system is connected with the servo proportional valve, an industrial air source is connected into the servo proportional valve, and the air source adjusted by the servo proportional valve is connected to the pressure air cylinder through an air pipe. A pressure air cylinder rod is connected with one end of each swing arm, the swing arms swing through fulcrums, the other end of each swing arm is connected with the movable supporting arm, the pressure air cylinder drives the swing arms to swing, and the swing arms drive the supporting arm to move. The driving mechanism, the polishing wheel and the expansion wheel are installed on the supporting arm. The driving mechanism drives the polishing wheel to rotate, and the polishing wheel drives