Precisely located suction assembly in compact spinning drafting frame

摘要

A drafting frame for leading sliver to a spinning station in a spinning machine has a pressure cylinder (3.1, 3.2) and a strainer drum (2.1, 2.2) between which the sliver is passed where the drum has, below its perforations (6), an annular channel (4) in which is located a suction insert (5) connected to a suction tube (9). Between tube and insert is a central support piece (8) with which the insert is mounted coaxially with the drum. Preferably the central support piece is set between two suction inserts, each of which is centred relative to a drafting cylinder (1), and via a bearing (10), is supported on the drafting cylinder on which the strainer drum is mounted. The bearing can be a needle bearing or a plain bearing. On the support piece is a fastening strip (13) which forms with the suction insert a spring-and- groove connector (14, 16) which runs in a curve round the drafting cylinder. The suction tube is connected via a slot (15) in the fastening strip to a suction chamber (7) in the insert for which there is a stop in the direction of the drafting cylinder's rotation. The insert is shorter in the axial direction than the distance between two strainer drums (2.1, 2.2).