Abstract: A method and apparatus for exchanging a bobbin on a bobbin holder of a spinning machine for a full bobbin stored on a spare bobbin frame of the spinning machine. The apparatus is in a service unit for the spinning machine and includes an intermediate support apparatus and a grip element movable between the bobbin holder, the spare bobbin frame and the supporting apparatus for sequentially transferring a full bobbin or a bobbin on the bobbin holder to the intermediate support apparatus, transferring a bobbin directly between the bobbin holder and the spare bobbin frame and transferring a bobbin on the intermediate support apparatus to the bobbin holder or the spare bobbin frame. The gripper element includes a vertically movable frame having a plurality of spindles for mounting bobbins thereon and the frame is rotatable in response to vertical movement thereof so the frame can be selectively moved along a path corresponding to the adjacent contour of the spinning machine.

Abstract: A positioning mechanism for a traveling automatic maintenance unit for a textile ring spinning machine or the like, which unit includes a carriage movable on spaced tracks along the spinning stations of the machine for automatically stopping at spinning stations that are determined to require maintenance. The mechanism includes a frame that is transversely pivotally mounted on the carriage on a longitudinally extending shaft. The frame carries an automatically operable maintenance mechanism that pivots with the frame transversely into operating position at a spinning station. Transverse movement of the frame is accomplished by a pneumatic piston-cylinder mechanism that manipulates a sliding element on a transversely extending rod of a slide guide with the frame connected to the sliding element by a connecting linkage.