(281) The description of the general construction of the machine thus given clears the ground for the detailed explanation which follows. For convenience it will be as well to begin by describing the mode of obtaining the motion of the spindles. This is illustrated in Fig. [152], which is a diagrammatic representation of the course of the bands and driving pulleys. The mule is driven from the line shaft, or a counter shaft by means of a strap passing over the pulley A fastened upon the shaft C. The latter is termed the “rim shaft,” and upon it the loose pulley B is also placed. Free to revolve and slide upon the same shaft is the spur wheel A1, formed with a large internal cone, the exact object of which will be hereafter described. The fast pulley is about 5 inches wide, and the loose pulley 51⁄4 inches, the diameter being about 15 inches. Thus, when the strap is on the fast pulley it is also partially on the loose pulley, which is always revolving. At the other extremity of the rim shaft a double, treble, or quadruple grooved pulley C1 is fixed, which is called the “rim.” Over this the endless cord or band driving the spindles is passed—being known as the “rim band”—its course being clearly shown by means of the arrows. It will be noticed that it is first passed round a carrier pulley on the carriage square, and then round the tin roller pulley on the tin roller shaft T, being then taken round the carrier pulley Y fixed at the end of the headstock frame, afterwards returning to the rim pulley. It will, of course, be understood that the explanation just given relates to the course of the rim band, considered as a single rope. When the rim is double or treble grooved, corresponding arrangements must necessarily be made in the rim band course. The rollers E are driven from the rim shaft by the train of wheels and the side shaft G shown, and the drawing out of the carriage is effected by the band passing round the scrolls at H and round the pulley Z. This will be more particularly described presently.
(282) Particular reference will now be made to Figs. [153] and [154], which are respectively longitudinal sections of the driving gear and back view of the same. The loose pulley B has formed upon its boss a spur pinion B1, from which, by means of a carrier wheel, the side shaft D is driven. On the other end of this shaft a pinion D1 is fixed, which gears with and constantly drives the spur wheel A1, this being the object of the overlapping of the driving strap previously referred to. The wheel A1 is formed, as shown, on its inner side with a large internal conical surface, which, at the proper moment, engages with a corresponding leather-covered surface formed on the pulley A. This engagement takes place for the purpose of backing-off, and the cone A1 is therefore known as the “backing-off cone” or “friction.” The engagement of the friction cone with the fast pulley causes it first to act as a brake, and the strap having been moved upon the loose pulley it then exerts sufficient force to revolve the backing-off cone in the contrary direction. To enable this contact to take place a ring groove is formed in the boss of the backing-off wheel, in which a claw engages, which is oscillated as afterwards described. The effect of this arrangement is that the rotation from the loose pulley B of the friction wheel A1, whilst it is engaged with the fast pulley A, causes the rim shaft to be rotated in the opposite direction to that normal to it. The direction in which the various parts revolve normally is clearly shown by the arrows. The extent of the backward movement of the rim shaft depends, of course, entirely upon the length of time during which the friction cone A1 is allowed to engage with that on the pulley A, this being regulated by the amount of yarn to be unwound.
(283) The rollers E are driven from a pinion G1 fastened on the rim shaft, by means of which the shaft G is revolved, and motion is thus given to a bevel wheel loose upon the short shaft coupling the two front lines of rollers. One half of a toothed or claw clutch is formed on the boss of the wheel, the other half of which is secured to but slides upon the coupling shaft, being formed with a ring groove on its boss into which the two arms of a claw are fitted so as to engage and disengage the clutch.
Fig. 152.J.N.
Figs. 153 and 154.J.N.
(284) On the boss of the bevel wheel is a spur wheel which, by means of the train of wheels shown, communicates the forward movement to the “back” shaft H on which are fixed the scrolls H1. On these the ropes or bands shown are wound, being attached to the carriage as shown in Fig. [152]. As the carriage extends to the right and left of the headstock, as explained, the back shaft H is similarly extended, and has placed upon it a number of scrolls at suitable distances apart, on which other bands are wound. This enables the carriage to be evenly drawn out throughout its entire length. The method of attaching the bands to the end frames of the carriage is shown in Fig. [155], and it will be seen that there is power of adjustment given, which enables the carriage to be “squared” or kept parallel with the roller beam. The last of the train of wheels P1, by which the back shaft is driven, is loose upon it, and forms one half of a clutch, the teeth of which are peculiarly shaped. The other half P slides upon the boss of a disc which is keyed upon the shaft, and has a ring groove in its boss, being ordinarily pushed up to its position by a spiral spring surrounding the back shaft and kept in compression by a stop hoop or collar which can be set up as desired. This, combined with the peculiar construction of the teeth, enables the clutch to open and its teeth to glide over one another in the event of any obstruction being offered to the free outward run of the carriage. The forked end of an L lever fits in the groove in the clutch, being oscillated as afterwards described.
Fig. 155.