Fig. 184.J.N.
(362) Mr. Richard Threlfall of Bolton has devoted himself to the construction of fine spinning mules, and has produced a self-acting machine, which is capable of spinning the highest counts. With a brief description of it as made by him, the present treatment of this machine must be closed. In the Threlfall mule the roller delivery after jacking is effected by a short shaft on which is a catch box, the outer surface of which constitutes a cam course, which is revolved from the twist shaft. On this cam shaft is the first of a train of wheels, which gear up to the roller, and the first wheel has motion given to it by a ratchet and pawl, the movement of the latter being controlled by the throw of the cam. The cam can be set so as to give a whole turn to the rollers, or only one flute, and by means of changes in the train of wheels further regulation can be made. The copping rail is specially constructed, so as to enable short cops of any shape to be easily built. The fallers are arranged so as to be very sensitive in action. The action of the quadrant is aided by a special contrivance consisting of a narrow pulley placed alongside the loose backing-off pulley, but fast on the shaft. Connected to the strap guide is a lever which is coupled to a rod suitably carried in brackets, and on which is a regulating screw and nut. This regulation is provided so that the passage of the strap on to the narrow pulley is effected as desired. The strap is prevented from traversing from the loose pulley by a catch, and the release of the latter is effected by a finger on a bracket fastened to the carriage square. When the latter runs in the finger pushes over a tumbler holding the catch in position and releases the latter. The weight of the parts then throws the strap over on to the fast narrow pulley, and the winding is thus accelerated. By fixing the finger and setting the adjusting screw, this motion may be brought into play at any desired moment. On the faller shaft is a bracket, to the outer edge of which is attached by a bolt or screw a grooved cam surface. To this is attached a cord actuated by the governor motion. By suitably setting the cam, winding is effected during each inward run with equal tension. A brake is applied to the faller shaft, consisting of a lever fastened to the carriage, one end of which engages with an inclined plane, and the other end has a cord attached passing over a pulley on the faller shaft. By tightening the band the faller is held perfectly steady. The combination of the last three motions effectually prevents snarls. A roller delivery motion is added, and the most perfect adjustment of the whole of the movements is provided. The spindles revolve at two speeds, the final or twisting velocity being about 8,000 revolutions per minute.
(363) Such is a description of the most intricate machine in the whole range of textile mechanics, which, although threatened more than once with extinction, is yet more largely used to-day than at any previous time. On it yarn of varying qualities can be spun, either soft or hard twisted. The yarn which is used for warp purposes is more commonly known as twist, and that employed for weft is known by that name. Weft yarn, as will be shown at the end of the next chapter, is always more softly twisted than warp yarn, and the mule spindles revolve in the opposite direction to that employed when the latter is spun. About the question of twists and the system of the arrangement of draughts throughout the whole process of spinning, a few words will be said in concluding the next chapter.
(364) The mule is used in a modified form to produce “doubled” warps-that is, two strands of yarn twisted together. When so employed, the machine is known as a “twiner,” and is constructed with a low creel. With the necessary alterations to suit the circumstances peculiar to the case, the machine is largely employed in certain districts. In its main features, however, it resembles the mule, and does not require a detailed description. Another modified form is used for spinning yarns made from waste, being nearly identical with the machine as employed in spinning fine worsted yarns. The student who is interested in this subject will find a description of the woollen mule in “Spinning Woollen and Worsted,” by Mr. W. S. Bright McLaren, M.A.
(365) A table is appended of actual productions from Messrs. John Hetherington and Sons’ mule. These are given from 74 machines for the ordinary working week of 561⁄2 hours. A great variety of counts are included, all of which were being spun at the same time. An additional table is given of productions from Messrs. Platt Brothers and Co.’s mule. An explanation of the value of the hank is appended to the next chapter.
Table 2.
ACTUAL PRODUCTIONS IN A WORKING WEEK OF 561⁄2 HOURS, FROM MESSRS. JOHN HETHERINGTON AND SON’S MULES.
| No. of Mule. | Hanks. | Counts. | Hanks per Spindle. |
|---|---|---|---|
| 2 | 77,250 | 39 | 31·14 |
| 4 | 70,750 | 43 | 28·52 |
| 6 | 71,000 | 43 | 28·62 |
| 8 | 75,500 | 41 | 30·44 |
| 10 | 65,750 | 32 | 32·42 |
| 12 | 68,750 | 28 | 33·90 |
| 14 | 61,750 | 36 | 30·44 |
| 16 | 71,750 | 45 | 28·73 |
| 18 | 69,750 | 45 | 27·94 |
| 20 | 72,250 | 45 | 28·94 |
| 22 | 71,750 | 45 | 28·73 |
| 24 | 71,000 | 45 | 28·43 |
| 26 | 71,250 | 45 | 28·53 |
| 28 | 71,250 | 45 | 28·53 |
| 30 | 72,250 | 45 | 28·93 |
| 32 | 73,000 | 42 | 29·23 |
| 34 | 72,500 | 42 | 29·03 |
| 36 | 61,500 | 36 | 29·97 |
| 38 | 66,750 | 32 | 32·52 |
| 40 | 62,000 | 38 | 30·21 |
| 42 | 58,500 | 38 | 28·50 |
| 44 | 62,750 | 36 | 30·57 |
| 46 | 62,250 | 38 | 30·33 |
| 48 | 63,250 | 36 | 30·82 |
| 50 | 60,250 | 38} 33} | 29·35 |
| 52 | 64,750 | 34 | 31·55 |
| 54 | 65,750 | 36 | 32·03 |
| 56 | 65,000 | 40 | 30·52 |
| 58 | 61,750 | 40 | 29·91 |
| 60 | 61,000 | 42 | 29·55 |
| 62 | 60,000 | 42 | 29·06 |
| 64 | 63,000 | 40 | 30·52 |
| 66 | 61,500 | 40 | 29·79 |
| 68 | 61,500 | 42 | 29·79 |
| 70 | 61,250 | 42 | 29·67 |
| 72 | 59,750 | 42 | 28·94 |
| 74 | 65,750 | 40 | 31·85 |
| Total Weight, 59,9201⁄2 lbs. Average Counts, 39·53. Average Hanks per Spindle, 29·88. | |||