Patent GB-768674-A (GB)
Title: Improvements in an automatic loom and a method of weaving thereon
IPC: D03D43/00
Filed: 1953-06-15
Abstract: 768,674. Automatic bobbin changing looms. LANEX SOC. ANON. June 15, 1953 [Jan. 6, 1953], No. 16351/53. Class 142 (2). Two-colour pick-and-pick weaving is performed on a 2-by-2 automatic pick-at-will loom (having the bobbin feeler and bobbinchanging mechanism at the same end) by omitting to pick a shuttle on the first and ninth revolutions of every ten, whereby each shuttle in turn becomes available for replenishment in the upper cell at the replenishing end, whilst the lower cell is empty to allow the ejected bobbin to pass through it into a shoot. On the first pick of a cycle, a shuttle arriving in the upper cell is felt as the box rises during beat-up; the box at the other end of the loom does not move, consequently the picker operates in an empty cell on the next revolution of the crank-shaft, so that no shuttle is picked and the lower cell at the replenishing end remains empty to permit replenishment (if necessary) of the shuttle that has been felt. On the seventh revolution of the cycle, the other shuttle arrives in the upper cell at the replenishing side and is felt as the box rises ; the next pick occurs from the lower cell, thereby enabling replenishment to take place in the top cell (if necessary) on the eighth beat-up movement; no shuttle is picked on the next revolution, since it is the turn of the replenished shuttle, and a revolution of the crank-shaft is needed to bring it level with the shuttle race. Colour selection is effected by the pattern chain, which sets the magazine to deliver one colour of bobbin during the first half of a ten-revolution cycle and the other colour during the second half. Fabric take-up. Since only eight picks are laid in ten revolutions of the loom, the takeup speed is set at four-fifths of the rate usual for the required pick density. Initiating bobbin changing. A floating lever 78, Fig. 5, is continuously oscillated by a cam-operated rod 73, the pivot of the lever being normally a pin 79 coupling it to a rod 80 leading to the magazine; at each oscillation, the other end 78a of the lever enters a slot (not shown) in a bracket 40a. On the picks preceding those on which bobbin changing is possible, a pin 40, operated by a connection 35b from the pattern mechanism, is pushed into the bracket 40a so as to block the slot ; on its next descent, the end 78a of the lever 78 encounters the pin 40 and fulcrums on it, whereupon continued movement of the rod 73 pulls the rod 80 downwards to initiate bobbin changing. This action is permitted only if the shuttle available for replenishment is depleted, in which case the feeler 74 slips sideways on the bobbin ; if the bobbin contains enough weft to last another ten-revolution cycle, the feeler is pushed forward, causing its mounting 81 to strike an arm 75b, whereby the pin 40 is withdrawn from the bracket 40a to prevent bobbin changing. Weft stop motion. To prevent stoppage on the revolutions when no weft is laid, a lever 23, Fig. 3, is lifted by a connection 30 from the pattern mechanism to hold up the centre weft fork (not shown), thereby preventing it from riding down its cam 21 into the notch 31. Shuttle box. When the transfer latch 38, Fig. 4c, is raised for operation by a striker 83 on the slay, a lever 36 encounters an extension 38b of the latch, by which it is pushed underneath a ledge 39 of the drop box to support it during bobbin changing ; the lever 36 is normally held clear of the ledge by a spring (not shown).