The invention relates to an automatic doffing trolley of a
spinning machine. The automatic doffing trolley comprises a doffing trolley body and an automatic doffing device. The automatic doffing device is arranged on a bottom plate located on the upper portion of the doffing trolley body. A pre-loosening mechanism of the automatic doffing device is arranged on the bottom plate of the doffing trolley body through a
spring steel plate. A pre-loosening block is fixed on the
spring steel plate. When the trolley moves forwards, the pre-loosening block moves forwards along with the trolley, is inserted into the lower end of a
bobbin, and enables the lower end of the
bobbin to ascend along an
oblique plane of the pre-loosening block. Then, under the action of a plane
cam, the pre-loosening block abuts against the lower end of the
bobbin, moves upwards in the direction parallel to the axis of a spindle blade and enables the full bobbin to break away from the spindle blade under the blocking action of a spindle hook. The bobbin bounced upwards enters a
manipulator device. The upper ends of claws of the
manipulator device clamp the upper end, without
yarn, of the full bobbin and then pull the full bobbin out. The pre-loosening force of the pre-loosening mechanism is parallel to the axis of the spindle blade and has little influence on a spindle bearing. The
manipulator device clamps the upper end, without the
yarn, of the bobbin, and the quality index of the
yarn can not be influenced.