Patent GB-190809709-A (GB)
Title: Improvements in and connected with Thin Place Detector Mechanism for Automatically Effecting Replenishment of Filling and Changing the Operation of the Loom on Detection of the Absence of Filling in the Fabric.
Filed: 1908-05-05
Granted: 1909-02-25
Abstract: 9709. British Northrop Loom Co., [Northrop Loom Co.]. May 5. Loom weft - replenishing mechanism ; temples.- When the weft fails and a thin place results, a detector 16, Fig. 1, which normally rests on the cloth, falls, and a shaft d<1> which controls weftreplenishing mechanism of the Northrop type is rocked. At the same time, the take-up is stopped and the cloth is let back, so that after the weftreplenisbing, the weaving is resumed at the place where weft failure occurred and the occurrence of a permanent thin place in the fabric is thus prevented. The detector is raised from the cloth so that it is out of action for a few picks, and is allowed to drop gradually on to the cloth again. The detector consists of a down-turned finger 14, which has a slotted and flattened shank 15 adjustably connected by a set-screw 17 to a plate 10, whereby the distance of the detector from the fell can be regulated. The plate 10 has slots 11 to receive the shanks of headed screws 12 on a carrier 9 on a member 6, which is adjustably connected by screws 7 to the other member 5 of a longitudinallyadjustable compound shaft. The plate 10 is prevented by the screws 7 from lateral movement, but can be moved backwards against the action of a spring 13 to prevent tearing, if the detector should become fast in the fabric. The rock-shaft 5, 6 turns in a bearing 4 on the breast beam A<40>, and in a bearing 3 on an arm 2 on a stand 1 secured to the support for the temple stand T'. The hub 19 of an arm 20, Figs. 1 and 2, is secured on the rockshaft. This arm has an upright elongated guide 21, which normally raises a latch 22 fulcrumed at 24 between ears on the lateral head of a lever 26, 26<X> fast on the rock-shaft d<1>. When the detector falls and the members 5, 6 are rocked, the arm 20 falls and allows the latch to fall into the path of a lever 29, 31, rocked by a cam 33. The latch 22 is thereby moved backwards, rocking the lever 26 and rock-shaft d'. The hub 19, Fig. 1, is connected by a spring 38 to the loosely-mounted hub 39 of a lifting-arm 37, which may be operated by a cam 44 on a disk 42. The disk 42 is turned against the action of a spring 48 by a link 45, provided with a longitudinally-slotted extension 46<x>, which receives an upright stud 47 on the lever 26, 26<x>. The high part of the cam 44 then engages and raises the arm 37, which raises the latch 22, the detector being also thereby raised from engagement with the ctoth. The disk is provided with ratchet teeth with which the lower tooth 53 of an escapement 53, 54 is normally caused to engage by a spring. At each rearward motion of the lever 29, however, a finger 55 causes the disengagement of the tooth 53 and the engagement of the tooth 54 with the ratchet teeth. After the lever 26 has returned to normal position, assisted by the action of a leaf-spring, the stud 47 having moved rearwardly in the slotted part 46<x>, the disk is allowed by the escapement mechanism to return gradually to normal position under the action of the spring 48, so that the detector falls gradually into active position, the cam 44 finally allowing the arm 37 to fall and free the latch 22. The lever 29 is operated once for every two picks, so that the weft-replenishing mechanism is actuated only when the shuttle is in the right-hand shuttle box. The temple may be adjusted laterally without changing the position of the detector by merely unclamping the collar 18, Fig. 1, the bracket or stand 1 being moved with the temple. Loom take - up motions. - The extension 26<x>, Fig. 2, of the lever 26, 26<x> causes two adjustable tappets 65, 66 to raise the take-up pawl 59 and detent 64, respectively, from the ratchet-wheel 58, thus stopping the take-up and allowing the cloth to be let back. By adjusting these tappets, the time during which the pawl and detent are kept out of action can be varied, the operating-cam 33 for the lever 29 being made without any dwell portion. Loom shuttle-races.-The shuttle-race may be made continuous, as no weft-fork is used.