Yarn doffing system of composite covering yarn and operation method

The yarn doffing system comprises a supporting plate and a yarn bobbin, a supporting frame is fixedly connected to the top of the supporting plate, two transmission rollers are rotatably connected to the interior of the supporting frame, the outer sides of the two transmission rollers are sleeved with a conveying belt, and transmission is achieved through the conveying belt; the top of the supporting frame is fixedly connected with an upper support, the conveying belt is symmetrically provided with two supporting pieces for containing yarn bobbins, along with transmission of the conveying belt, a transmission gear is connected with a fixing rack in a meshed mode, then a protruding block in the transmission gear drives a fixing shaft to rotate, and the fixing shaft drives a fixing disc to rotate; and the yarn cylinder rotates in the transmission process on the conveying belt, and it is guaranteed that yarn on the outer side of the yarn cylinder can be fully treated through subsequent cleaning. 本发明公开了一种复合包芯纱的纱线