Abstract: A draw frame for a spinning machine is provided with roving blocking mechanism associated with its inlet rollers actuable on rupture of the remittant thread to arrest movement of the roving and is further provided with a sensor for detecting the continuity of the roving being fed from a source of supply and a roving clamp situated between the sensor and the blocking mechanism. The blocking mechanism and the roving clamp are arranged to be simultaneously operated in response to a signal from the sensor or in response to rupture of the thread.

Abstract: A drawing frame for a spinning machine is provided with a blocking mechanism movable into a position between the upper and the lower feed rollers, in the event of yarn breakage, to lift the roving from contact with the driven roller. The blocking mechanism holds the roving. A roving holder is coupled to the means for actuating the blocking mechanism for synchronous operation and is provided downstream of the inlet roller. It comprises a table extending beneath the roving and a rotatable shaped arm above the roving which arm is movable by the switching mechanism to simultaneously hold the front end of the roving. The table is provided with a guide lug at its free end extending at an upward angle relative to the rotatable arm and the arm is covered with an inclined member having a slope running toward the guide lug.

Abstract: A bearing rail is provided extending along each side of the draw frame and spaced laterally from the outer edges of the double upper rollers. At the end of the each rail, in the area when the thread exits from the exit rollers, each rail is provided with two carriers, one of which is provided with a light source and the other which with a light receiving photo-cell. The light source on one side of the drawing frame is arranged in association with the thread being drawn adjacent the photo-cell on the other side so that the light source causes this remote thread to cast a shadow on the photo-cell adjacent to it. Similarly the light source on the other side, the thread remote from it and the photo-cell opposite it are also aligned. The shadow on each photo-cell produces an alternating current which is then independently fed to a circuit and switch means, housed at the inlet end of the bearing rail.