Abstract: A fabric for strengthening flat-shaped articles consisting of warp threads and woof threads which form a basic fabric having a connected edge area which is strengthened relative to the basic fabric.

Abstract: A fabric for strengthening flat-shaped articles consisting of warp threads and woof threads which form a basic fabric having a connected edge area which is strengthened relative to the basic fabric.

Abstract: A fabric for strengthening flat-shaped articles consisting of warp threads and woof threads which form a basic fabric having a connected edge area which is thinned relative to the basic fabric.

Abstract: A device attached to a spinning or twisting machine, designed to monitor the integrity of two threads merging under tension into a yarn, has a carrier swingable about a horizontal axis and provided with a thread guide, such as a pair of parallel pins, bracketing the yarn downstream of the merger point. A rupture of either thread lets the carrier rotate, e.g. by gravity, from an unstable normal position by half a turn into a stable off-normal position to impede the advance of the remaining intact thread whereby the latter also breaks. Such action, however, is prevented when the yarn is under reduced tension, as during shutdown or startup of the machine, by a locking mechanism arresting the carrier in its normal position. The locking mechanism may include an electromagnet whose winding can form part of a circuit signaling the displacement of the carrier into its off-normal position in response to a thread break.

Abstract: A device for detecting a break in one of two tensioned threads merging into a yarn comprises a support on which a guide member with two yarn-bracketing pins is pivotable about a horizontal axis. The guide member is provided with a hole penetrated by a stud of smaller diameter having a head with two or more chordal ridges of different peripheral widths each of which, when brought into a horizontal position above the stud axis, contacts a rabbet on the guide member disposed below its center of gravity to hold that member in a metastable position from which it is dislodged by a difference in the tensions of the two threads. When that difference surpasses a certain threshold, upon rupture of one of the threads, the guide member tilts into an unstable position from which it gravitates through substantially half a turn into an inverted stable position, thereby entangling the remaining intact thread with its pins and inhibiting the advance thereof so that it, too, will rupture.