A waste heat recovery device comprises a device body. A storage cavity body is arranged on the right side of the device body, a storage cavity is formed in the storage cavity body, a rotating cavity is formed in the device body, a first motor is fixedly mounted in the left end wall of the rotating cavity, a first rotating shaft is in power connection with the right end of the first motor, a firstconnector is slidably connected with the rotating cavity in a matched manner and fixedly mounted on the outer surface of the first rotating shaft, a first annular groove is formed in the inner wall ofthe rotating cavity in a communicated manner, an opening control component can rotate in the first annular groove and is fixedly mounted on the outer surface of the first connector, a second connector positioned on the right side of the first connector is rotatably mounted in the rotating cavity, the right end of the first rotating shaft is rotatably connected with the left end wall of the secondconnector in a matched manner, and a second annular groove positioned in the right side of the first annular groove is communicated with the outer surface of the rotating cavity.