Patent GB-191110955-A (GB)
Title: Improvements in Automatic Weft Replenishing Looms.
IPC: D03D45/20
Filed: 1911-05-06
Granted: 1912-03-07
Abstract: 10,955. British Northrop Loom Co., and Hollins, D. M. May 6. Weft-replenishing mechanism; change box motions.-In automatic weft-replenishing looms, two or more shuttles are used, one of which makes two or a multiple of two picks followed by two or a multiple of two picks from t h e other shuttle or shuttles, thus minimizing the shading effects resulting from slight variations in colour &c. of one supply from the preceding or following supply of weft. A weft-feeler is arranged at the non- replenishing side of the loom so as to project into one of the changeboxes and detect substantial exhaustion of weft in the shuttle next to become active, whereupon, after the changeboxes have moved and the substantially-exhausted shuttle has been picked into the single shuttle box at the opposite side of the loom, a fresh bobbin &c. is transferred into it. The change-boxes 12, 13, Fig. 3, may be operated by a pin 19 eccentrically mounted on a wheel 20 driven by a pin-wheel 21, which is driven by a hook 23 operated by a crank 24 on a wheel 26 geared to the crank shaft 28, so that the wheel 21 is given a quarter-revolution and the wheel 20 a half-revolution to change the boxes after each two picks. To enable a shuttle to make more than two picks in succession if necessary, the hook 23 may be raised out of engagement with the pin - wheel 21, when required, by a weighted lever 29 connected by a cord 32 to a lever 31 provided with a pin 31' to engage holes in or blanks on a card cylinder 33 or on cards thereon. The cylinder is raised and lowered by an arm 34 and lever 35, so that, if the pin 31<1> engages a hole, the weighted end of the lever 29 raises its opposite end 29<1>, which thus prevents the engagement of the hook 23 with the pin-wheel. If the pin 31<1> engages a blank, the hook 23 engages the pin-wheel and the boxes are changed. The weft-feeler 3, Figs. 1 and 3, is provided with two feeler fingers 36, 36', the fingers being so positioned that one of them engages the weft in the inactive shuttle, while the other passes above or below the active shuttle when the lay beats up. A slotted member 37 is engaged by a spring -controlled bar 39, connected by a flexible connexion to the lever 31, so that when the pin 31<1> on this lever engages a hole in the cylinder 33 the lever 39 is turned by its spring and acts on the member 37, thus moving the feeler into inoperative position. When, however, the pin 31<1> engages a blank, which occurs one pick previous to a change of boxes, the lever 39 is withdrawn from the member 37, which then allows the feeler to swing into operative position. When the shuttle about to become active is substantially exhausted, a dog 4, Figs. 1 and 8, on the feeler 3 remains in position to support a notched block 5 on a latch 6, pivoted to an arm 7 and provided with a bunter 43, so that, when a cam-actuated actuator 42 is moved forwards, the bunter 43 is engaged by the inclined part 45<1> of a block 45 on a vertically-slidable member 44 on the actuator. The boxes then change and the feeler is moved'into inoperative position, so that the latch is no longer supported by the dog 4 but, nevertheless, is maintained in a raised position by the dog 4. After the boxes have changed, therefore, and the substantially-exhausted shuttle has been picked to the replenishing side of the loom, the bunter 43 is guided into a notch 42<1> in the actuator, which completes its forward movement, the arm 7 being then oscillated and the replenishing-mechanism actuated. If the shuttle is not sufficiently exhausted, so that the dog 4 does not engage the block 5, the bunter 43 engages beneath and raises the block 45 on the advancing actuator. When the actuator moves forwards, a finger thereon engages a cam-surface on a finger on the latch 6, thereby raising the latch to permit the dog 4 to engage the notched block 5 when replenishment is indicated. Weft-fork mechanism 8, Fig. 1, may be arranged at the replenishing side or, as shown, at the change-box side to stop the loom when the thread from the active shuttle fails or is broken. When the shuttles give only two picks in succession, the cylinder 33, Fig. 3, being dispensed with, the weft-feeler 3, Fig. 11, is moved out of operative position when the boxes are being changed by a bowl 57 on a rod 56 operated by a lever 55 controlled by a spring and cam 54. When more than two shuttles are used, the weft-feeler is given a rising and falling movement so as only to coact with the shuttle next to become active. The various shuttles may be provided with wefts of different colours.