There has already been proposed a device of the type generally described above, featuring a cylindrical tube inclined from the vertical below a sliver guide, the bottom end of the tube being mounted on a supporting element, and the top end or upper part being accommodated in a ball bearing, the outer race of which is located in a horizontal plate describing a gyratory movement through the action of two crankshafts coupled by drive elements, such that the tube will undergo a generally nutational movement in operation, in the sense that the tube will move in a generally conical path about its lower end. An exemplary such device is disclosed in a commonly assigned U.S. application Ser. No. 88,814 filed Oct. 29, 1979, (Schopper), entitled "Apparatus for loading a rope-like strand of fibers into spinning cans." Attention is also invited to commonly assigned earlier U.S. application Ser. No. 920,822, filed June 30, 1978, now U.S. Pat. No. 4,173,057, corresponding to Swiss Pat. No. 611,239. With such a device in operation, the sliver is piled into a can in cycloidal loops, but there is a tendency for the sliver to accumulate or concentrate in particular areas of the can in an undesired manner, the sliver typically accumulating in the center of the can. This applies in particular to the situation in which the tilted tube and the cans at the delivery end of the device are of relatively small diameters, as in feeding open-end frames.
An object of the instant invention is to remove this shortcoming in the piling operation, thereby bringing about improved distribution of the sliver in the piling operation, principally by shifting the axis of the cycloidal loops. In general, this object is met by locating the crankshafts on a second horizontal plate which also describes a gyratory movement through a second pair of coupled crankshafts, the first pair of crankshafts being driven more slowly than the second pair. Preferably the first pair of crankshafts is rotated between ten degrees and fifty degrees for every complete rotation of the second pair of crankshafts.
Other and further objects, advantages and features of the instant invention will be apparent to those skilled in the art from the ensuing description of a preferred embodiment, taken in conjunction with the appended drawing.