Patent GB-234265-A (GB)
Title: Improvements in weft feeler mechanism for looms for weaving
IPC: D03D51/34
Filed: 1924-05-07
Abstract: 234,265. British Northrop Loom Co., Ltd., (Northrop Loom Co.). May 7, 1924. Weft-feeler arrangements. - Devices are employed whereby weft-feeler mechanism is caused to have short periods of activity, during which the feeler is moved into contact with the weft at each beat up, and intervening longer periods of inactivity, during which the feeler is held retracted in an inoperative position out of contact with the weft, until the weft depletion reaches the danger point, whereupon the feeler is allowed to remain active and to contact with the weft at each beat up, until substantial exhaustion of weft is indicated and weft replenishment is initiated or the loom is stopped. The invention is shown applied to weft-feeler mechanism of the known type wherein an inclined feeler 20, Figs. 1 and 4, passes through an opening in a slide 17 and through a swivel bearing 21 supported by a bracket 22 on the feeler stand, a spring 31 between the bearing 21 and a bridge &c. 30 on the feeler tending to move this to its rearward feeling position. The slide 17 is connected by a transmitter 16 to a bell-crank 12, which is rocked when the slide 17 moves laterally, thereby causing a pivoted member 10 on an arm 7 on an arm 5 on a rock shaft 4 to move into the path of an operating member 8, whereby the shaft 4 is rocked and replenishment of weft is initiated. Various arrangements are described for holding the feeler retracted in its frontward inoperative position away from the lay for an interval of time and then freeing it from the holding means so that it may be moved by the spring 31 into feeling position. If a working supply of weft is present in the shuttle the feeler is again moved frontwards into the control of the holding means and again held retracted and inoperative for an interval and then released. This continues until the weft is so depleted that it does not move the feeler sufficiently far frontwards to be engaged by the holding means, and subsequently the feeler acts at each beat up to detect the condition of the weft in the shuttle until substantial weft exhaustion is indicated. In one arrangement, a catch 43 pivoted to a downwardly-extending lug 41 on an adjustable block 32 has a series of teeth 46 for engaging a tooth &c. 47 on the bridge 30 on the feeler and thus holding the feeler in a retracted inoperative position. The catch 43 is connected at 48 to a controller arm or rod having an adjustable part 58, 59 and a yielding part 53, 54, 55 whereby the catch is moved upwardly into operative position. The controller arm &c. is connected at its lower end to a bellcrank lever 61 carrying a pin 64, which engages a block &c. 65 on a spring-controlled finger 66. This finger is moved endwise at intervals by pins with rounded heads 82 detachably secured to a wheel 72 forming part of the take-up mechanism. The lever 61 is thereby rocked and the controller arm &c. depressed thereby releasing the catch 43 to allow the feeler to move into operative position at intervals. This occurs until the feeler detects a near approach of substantial exhaustion of weft. At this point the feeler is not moved sufficiently far frontwards for the catch 43 to engage and hold the feeder, which consequently thereafter remains operative in the usual manner, to engage the weft at each beat up, until substantial weft exhaustion is indicated. In another arrangement, the feeler is provided with notches at its front end engaged by a tooth on a spring-controlled detent, which is rocked to free the feeler at intervals by a flexible sheathed wire or rod operated by actuators on a wheel of the take-up mechanism. In another arrangement, the feeler is held inoperative by a spring-controlled detent 101, Fig. 12, pivoted at 102 to a carrier &c. 103, which is pivoted at 104 and has an adjustable follower 114 acted upon by a notched rotating disc 113. When the follower enters the part 113<2> of the notch of the disc, the detent rocks to release the feeler. When the follower enters the part 113<3>, the detent assumes the position B and engages a projecting portion 30<1> of the bridge 30 of the feeler when this is moved frontwards, and when the detent is rocked further as the follower moves up the notch, it carries the feeler frontwardly to inoperative position, in which the feeler remains until the detent again engages the notch. Another arrangement is described wherein a slide carries a spring-controlled detent for engaging a tooth at the front end of the feeler stem.