Protective device of electric speed reducer

The utility model provides a protection device of an electric speed reducer, which comprises a protection box and a speed reducer body arranged in the center of the protection box, four corners in the protection box are respectively provided with a positioning piece, each positioning piece comprises a rubber shock pad, the inner wall of each rubber shock pad is connected with a mounting frame plate, and the mounting frame plates are connected with the speed reducer body. One side of the mounting frame plate is connected with a heat dissipation arc plate, a heat dissipation channel is arranged between the mounting frame plate and the heat dissipation arc plate, and a buffer part is arranged between every two positioning parts; a plurality of opposite limiting grooves are formed in the front side and the rear side of the protection box, a heat dissipation block is arranged in each limiting groove, the heat dissipation blocks are hollow, dust filtering nets are installed on the front side and the rear side of ea