Abstract: The grippers are mounted on a doffer bar so as to disengage from both the top and bottom of the bar should a mis-alignment occur relative to a bobbin tube. The removal or separation of a gripper from the bar causes a pneumatic or electrical signal to be generated which can be used to indicate the individual disturbance location. A light may also be provided at each gripper station in order to indicate a position of a disturbance.

Abstract: An apparatus for carrying out a block-change in a ring spinning machine, in which a block of roving bobbins which each supply an associated spinning station are changed together when the rovings wound on the bobbins run out. Preferably, more than one block of roving bobbins is provided. The roving bobbins used to form a block are combined in such a manner that all of them have at least substantially the same length of roving wound on them. The end of the roving on at least one of the bobbins of the block is detected before that end passes through the associated drafting unit, and the block-change is triggered at an instant of time when the roving end has not yet passed through the drafting unit.

Abstract: The grippers are mounted on a doffer bar so as to disengage from both the top and bottom of the bar should a mis-alignment occur relative to a bottin tube. The removal or separation of a gripper from the bar causes a pneumatic or electrical signal to be generated which can be used to indicate the individual disturbance location. A light may also be provided at each gripper station in order to indicate a position of a disturbance.

Abstract: The grippers are mounted on a doffer bar so as to disengage from both the top and bottom of the bar should a mis-alignment occur relative to a bobbin tube. The removal or separation of a gripper from the bar causes a pneumatic or electrical signal to be generated which can be used to indicate the individual disturbance location. A light may also be provided at each gripper station in order to indicate a position of a disturbance.

Abstract: The method and apparatus for supplying a reserve feed stock to a spinning machine or spinning position thereof, contemplates monitoring the operational state of a production feed stock and upon reaching a predeterminate operational state thereof, such as near depletion or depletion of the production feed stock, or even rupture thereof, bringing a reserve feed stock previously held in readiness into a production position where such reserve feed stock now assumes the role of a production feed stock. Consequently, downtime of the spinning machine or spinning position can be minimized and its operation at least partially automated since there is always available a reserve feed stock to allow for essentially continuous or continual production of a spun yarn or thread. One specific piecing technique uses a movable member for placement of a reserve feed stock into the travel path of a production feed stock such that piecing of these two feed stocks is reliably attained.

Abstract: A reserve feed stock is pieced with a production feed stock, particularly a roving of a ring spinning machine. The piecing operation can be accomplished by applying twist to predetermine portions of the reserve and production feed stocks and then releasing such applied twist upon separation of the reserve and production feed stocks at predeterminate locations thereof.