GB852063A - Improved thread fault responslve means primarily for lace machines - Google Patents

Abstract

852,063. Lace machines. LACE RESEARCH ASSOCIATION. Jan. 24, 1957 [Nov. 2, 1955], No. 31303/55. Class 74 (1). Mounted on a bar extending across a sheet of threads in a textile machine (e.g. the point bar 1 or 2 of a lace net machine) is thread fault responsive means comprising a plurality of units, each unit incorporating a plurality of feelers 3, each individual to a different thread, and an opposed feeler 4 common to a plurality of threads, the feelers being connected to an electric circuit and so arranged that, when a thread breaks, its now unsupported feeler 3 is free to move relatively to the opposed feeler 4, to render the circuit operative. A visual and/or audible warning is consequently given, or the machine is stopped. The feelers 3 are hingedly supported, from a common pivot, in tricks in a block 5 of insulating material and are biased, each by a leaf spring 8 acting on a cam 3a on the feeler. Rounded thread-engaging portions 3b are provided. The feeler 4, in the form of a flap, is also hung from the block 5, has a threadengaging part 4d, and is biased by a spring 11. In their rest positions, the feelers 3, 4, constituting contacts, are located out of contact, against stops. The oscillation of the bobbin threads T and the beating-up movements of the point bar result in periodic engagement of the threads T with the feelers 3 and 4 which are thereby moved, but together and so out of contact, until a thread supporting one of the feelers 3 breaks or becomes slack. The feelers 3 may be provided for some only of the threads of the front point bar in a lace net machine, and the feelers 3 on the back point bar may be wide enough to engage the threads in shogged and unshogged positions. In a modification, the feelers may be held stationary in the path of the oscillating bobbin threads. The sheet of threads may remain in a fixed plane. In this last event, either the feelers may be displaced, periodically, into and out of engagement with the threads; or the feelers may be permanently in engagement with the threads, their contacts forming one switch in a circuit containing also a second switch operated periodically to test the circuit for continuity. The feelers, instead of constituting contacts, may carry them, or merely operate them.