Modern Cotton Spinning Machinery, Its Principles and Construction

by Joseph Nasmith

Fourth. During this period “winding” takes place. The rollers are stationary; the carriage is “running in” at a variable speed; the spindles are revolving in the same direction as when twisting; and the winding faller is operated so as to guide the yarn on the cop.

Fifth. The carriage comes to rest; the faller and counter faller are released; the roller driving gear is re-engaged; the strap is moved on to the fast pulley and the driving band put in motion; and the drawing out gear is again engaged.

With this the cycle of movements is completed, and the whole of the operations begin anew.

(273) There are thus five periods, viz., 1st, twisting; 2nd, arrestation; 3rd, backing-off; 4th, winding; and 5th, re-engagement. In addition to these, when fine yarns are spun, there is sometimes a sixth period, which takes place immediately after the termination of the first as at present defined. This is a period of supplementary twisting after the rollers have stopped. This operation is sometimes known as “twisting at the head,” and will be dealt with at a later stage.

(274) It is thus indicated that at various times one part of the mechanism performs different functions. The rollers revolve for the whole or part of the first period and remain stationary afterwards. The spindles revolve at a constant and maximum velocity in their normal direction during the first period, at a slower but constant velocity in the reverse direction during the third period, and at a variable speed in their normal direction during the fourth stage. The carriage makes its outward run at a regular speed during the first period, is at rest during the second and third, and makes its inward traverse at a variable speed during the fourth. The winding faller remains stationary and free from contact with the yarn until the third period, when it makes a rapid descent to the winding point, after which it first descends quickly to its lowest point, and then ascends slowly to the nose of the cop during the fourth. The counter faller remains below and out of contact with the thread during the first and second periods, and ascends during the third, remaining in contact with and sustaining the yarn until the termination of the fourth.

(275) This preliminary explanation will enable the detailed description following to be more easily understood and appreciated. As there are many variations in the construction of the mule it is desirable to select one of the most widely used, and for this reason the machine constructed by Messrs. Platt Brothers and Co. has been chosen for description. Front and back perspective views of the machine are given in Figs. [149] and [150]. The Parr-Curtis mule is also largely employed, and many modifications of it exist. All the root principles which are contained in the machine are, however, found in the Platt machine. That is to say, it contains mechanism founded upon certain rules which are essential to all mules, so that, although the details may be, and are, varied, the main features are identical. A detailed description of its mechanism, therefore, will enable the subject to be fully understood, but, at the close of the chapter, particulars will be given of special features in other makers’ machines. To enable the construction of the machine to be more fully grasped, a series of diagrammatic views are given of each motion separately, and the reference letters are arranged so that each part is marked with the same letter in all the views in which it occurs, although the same letter, in some cases, refers to various parts in different diagrams.

Fig. 151.J.N.

(276) It may be first explained that the greater number of the parts by means of which the required motion is given to the various portions of the mechanism are contained in a longitudinal framing placed in the centre of the machine, this part of the mule being called the “headstock.” At right angles to the headstock, and at each side of it, the rollers and carriages extend for the entire length of the machine. The arrangement of a “pair” of mules is clearly shown in Fig. [151], the machines being usually placed with their headstocks zig-zag to one another. The carriage of one mule is coming out while that of the one opposite to it is at the roller beam, this arrangement permitting the free movement of the workman attending to the machines, and preventing the broken threads in each machine requiring piecing at the same time. It might, perhaps, be explained that “piecing” is always effected when the carriage is making the first part of the outward run, so that some inconvenience would arise if both carriages were in that position at the same time. A special motion is sometimes fitted by which each carriage is released alternately by the movement of the carriage opposite to it. Referring now to Fig. [151], H represents the headstocks of the two mules, E the lines of rollers, F the end frames, and O the carriages. It will be noticed that the headstock divides the machine into two portions of unequal length, each of which contains its own rollers and spindles. The special object of this is to enable the mules to be placed in closer proximity than could be done if both sides were of the same length, and the headstocks were placed quite opposite to each other.