A false-twist apparatus of the type referred to is shown, for example, in commonly owned U.S. Pat. No. 4,226,080. As explained in that prior patent, the threading of such an apparatus--i.e. the introduction of a yarn into the region of disk overlap between the several shafts--is a relatively complex operation; the improvement disclosed and claimed in the patent relates to a loading device to be used for this purpose.
From German laid-open specification No. 23 39 416 it is known to provide two relatively swingable members on which three disk-carrying shafts of a false-twist apparatus are rotatably supported, with one shaft journaled in both members at their fulcrum while the journal bearings of the other two shafts lie at respective extremities of these members remote from that fulcrum. A relative swing of the support members from a working position, in which their disks are overlappingly interleaved, and an idle position, in which they are separated from one another, enables the insertion of the yarn into the twisting region. According to that disclosure, the shaft centered on the pivotal axis of the two members is continuously driven by a motor and is coupled by respective transmission belts with the other two shafts which therefore are always entrained thereby. While the continuous rotation of all three shafts is described in that publication as an advantage allegedly avoiding the risk of thread rupture, it has been found in practice that a relative swing of the two support members about a pivot constituted by a rotating shaft gives rise to oscillations which are also transmitted to the two outlying journal bearings whereby all three of these bearings are subjected to accelerated wear.
German laid-open specification No. 29 43 279 discloses an alternate false-twist apparatus of this general type in which two shaft-carrying support members are independently swingable about fixed fulcra lying on opposite sides of a third shaft. Such an arrangement prevents the interconnection of the shafts by transmission belts or the like so that each shaft must be provided with its own drive means.
USPTO Backgrounds
USPTO Backgrounds