Auxiliary transmission device for upgrading from single-side coating to double-side coating

The invention provides an auxiliary transmission device for upgrading from single-sided coating to double-sided coating. The auxiliary transmission device comprises a friction roller, an upper belt pulley, a lower belt pulley, a magnetic powder clutch, a coupler and a transmission motor, inverted conical surface shaft heads are arranged at the two ends of the friction roller; the upper belt pulley and the lower belt pulley are connected through a triangular belt, the lower belt pulley is arranged at one end of a roller shaft of the friction roller and at the position far away from the inverted conical surface shaft head, the upper belt pulley is arranged on an output shaft of the magnetic powder clutch, one end of the coupler is connected with an input shaft of the magnetic powder clutch, and the other end of the coupler is connected with the output shaft of the magnetic powder clutch. The other end is connected with the transmission motor; and the transmission motor is used for driving the friction roller. A