Patent GB-191401455-A (GB)
Title: Improvements relating to Sliver Drawing and Doubling in Machines for Treating or Preparing Flax and other Fibres.
IPC: D01H5/38
Filed: 1914-01-19
Granted: 1914-11-05
Abstract: 1455. Mackie & Sons, J., Sinton, V. W., and Kirk, R. Jan. 19. [Cognate Application, 4996/14.] Carding - engines; gill boxes and frames; drawing-frames.-In a device for varying the speed at which a continuous sliver &c. is drawn forward according to its weight, the sliver &c. passes over a weighing-table, the movements of which are utilized to control the speed of the drawing-head &c. receiving the sliver &c., or of the machine delivering the sliver. In Fig. 5, the sliver is shown passing from a carding- engine 9 to a drawing-head 12 over a weighing- table 23, which moves up and down according to the variations in the weight of the sliver. The table, when a normal sliver is passing over it, stands slightly above the level of the tables 10, 11. The sliver acts to damp any vibration of the table 23 due to variations in the weight of the sliver. The drawing - head is driven through a belt 16, Fig. 1, passing over expanding pulleys 14, 15, which are controlled from a shaft 44, Fig. 2, through a worm 17, toothed segment 18, connecting-rod 21, and bell-crank 22. The weighing-table 23 is carried by rods 24 supported by counterbalanced levers 25 and levers 28 connected through a link 30 to a lever 31 carrying a guard-plate 32. This plate turns about a shaft 33 carrying a pair of ratchet-wheels 37. The ratchets are engaged by double pawls 38 which are continuously oscillated through connexions 54 by eccentrics on the shaft 13. The eccentrics are arranged to operate the pawls alternately. When the sliver is of normal weight and the table 23 stands at its usual height, the guard-plate 32 is in such a position that the pawls oscillate over it and are held out of engagement with the ratchet-wheels. If the table 23 moves from its normal position, the guard-plate is moved to one side, and the pawls step the ratchetwheels in one or other direction and rotate the shaft 44 through bevel-gearing 35, 36. To readjust the speed when a portion of sliver of normal weight follows a portion of irregular weight, the length of the connexions 54 is adjusted by screws operated from the shaft 44 to alter the centre about which the pawls oscillate in accordance with the movement of the guard-plate. The drive may take place through a differential gear, one member 8, Fig. 7, of which is controlled by the shaft 33, which is driven by a ratchet device. The pawls 38 are carried by arms 39 operated by eccentrics. A number of pawls are arranged and operated by eccentrics arranged at equal angles round the shaft, and these impart a fairly continuous rotation to the shaft 33. The speed is varied by the alteration in position of the guard-plate, which uncovers more or fewer teeth and allows each pawl to turn the shaft a greater or less amount. The rotation of the shaft 33 may be transmitted through a spring coupling. The guard-plates operated by the weighing-table 23 are so arranged that, where there is no sliver on the table, its position is such that the shaft 33 is rotated at such a speed that the driven member of the differential gear does not turn. The ratchet-mechanism may drive the drawing-head or whatever machine receives or delivers the sliver directly, or the movements of the weighing-table may be utilized to control by electrical means either a motor which drives the machine, or the position of a belt on cone pulleys. If applied to doubling, drawing, and roving frames, a device may be provided to delay the variation in the speed of the rollers for a suitable period after the movement of the weighing-table. According to Provisional Specification 4996/14, the guardplate may be provided with a locking-device to prevent it from being moved by the drag of the pawls.