Doffer Device having a Double Gripper for a Spinning Machine

A doffer device for a spinning machine having a plurality of spinning stations, the doffer device configured to remove full bobbins from spindles on the spinning machine and place empty tubes on the spindles, the doffer device comprising:

• a plurality of gripping devices, each gripping device assigned to one of the spinning stations and comprising a rotatable gripping unit;
• each gripping unit comprising a bobbin gripper that grips the full bobbin and a tube gripper that grips the empty tube;
• each gripping unit rotatable between a gripping position in which the full bobbin can be gripped on the spindle and a placement position in which the empty tube can be placed on the spindle;
• a rotating device configured with the gripping units to rotate the gripping units about an axis of rotation such that neighboring ones of the gripping units are rotated with a time lag relative to one another;
• and
• wherein the rotating device is driven by a toothed belt.

A method for removing full bobbins from spindles on a spinning machine and for placement of empty tubes on the spindles using a doffer device, wherein the doffer device comprises:

• a plurality of gripping devices, each gripping device assigned to one of the spinning stations and comprising a rotatable gripping unit;
• each gripping unit comprising a bobbin gripper that grips the full bobbin and a tube gripper that grips the empty tube;
• each gripping unit rotatable between a gripping position in which the full bobbin can be gripped on the spindle and a placement position in which the empty tube can be placed on the spindle;
• a rotating device configured with the gripping units to rotate the gripping units about an axis of rotation such that neighboring ones of the gripping units are rotated with a time lag relative to one another;
• the method further comprising:
• engaging the empty tube from above by placing the tube gripper over the empty tube;
• gripping the full bobbin from above by placing the bobbin gripper over the full tube;
• moving the gripping unit from the gripping position to the placement position;
• placing the empty tube onto the spindle from above with the tube gripper;
• rotating neighboring ones of the gripping units with a time offset relative to one another;
• and
• driving the rotating device with a toothed belt.

A gripping device configured for use on a doffer device to remove a full bobbin from a spindle on a spinning machine and to place an empty tube on the spindle, the gripping device comprising:

• a gripping unit rotatable about an axis of rotation (D), the gripping unit rotatable between a gripping position in which the full bobbin can be gripped on the spindle and a placement position in which the empty tube can be placed on the spindle;
• a rotating device configured with the gripping units to rotate the gripping units about an axis of rotation such that neighboring ones of the gripping units are rotated with a time lag relative to one another;
• a bobbin gripper configured on the gripping unit and comprising a bobbin receptacle that is open at the bottom for being placed over the full bobbin to grip the full bobbin, the bobbin gripper having a bobbin gripper axis;
• a tube gripper configured on the gripping unit and comprising a tube receptacle that is open at the bottom for being placed over the empty tube to grip the empty tube, the tube gripper having a tube gripper axis;
• and
• wherein the rotating device is drivable by a toothed belt.