FIG. 8.
FIG. 9.
Yarn is guided between the flanges of bobbins at a uniform pace by means of guides, J, carried upon guide-rails, K, supported in brackets, L, and operated by a heart-cam, M. On the end of the driving shaft, A, is a worm, N, which gears with a worm wheel, O, with which is compounded a pinion, P, to drive wheel, Q, to which the cam M is secured. As the cam revolves, it acts alternately upon two runners, R and S, carried upon studs secured to the sliding base, T, of brackets, L, whereby the latter receive a reciprocal motion, as indicated by arrows, U and V.
Winding Machines for Weft.
When weft yarn is in an unsuitable form to be placed within a shuttle it is usually wound upon paper tubes, or wooden bobbins, by means of one of the many systems of “pirn” winding. The chief parts of the prevailing type of machine used for that purpose are represented in Figs. [8], [9], and [10], which are end and front elevations and plan respectively. Passing centrally down the machine is a tin drum, B, on driving shaft, A, for the purpose of driving a number of wharves, C, arranged at regular intervals on each side of the machine. Fixed immediately above each wharve is a metal pirn cup, D, having a conical interior, for the reception of a pirn bobbin, E. When in position, a long spindle, F, having a heavy head-piece, G, passes through a bobbin tube and enters a rectangular hole in the wharve immediately below. The lower portion of a spindle which enters the wharve is also rectangular in cross-section, and therefore revolves with its wharve. At the same time, bobbins are driven by causing a projection, H, below spindle heads to enter a slot in each bobbin head.
FIG. 10.
Each thread passes from its source, over several stationary bars, to impart the required degree of tension to it, thence over guide-rail, I, by which it is guided up and down (as indicated by arrows, J) between the extremities of a pirn cup, as it passes through an opening, K, in the latter, and on to its bobbin. In consequence of yarn being built upon a bobbin within a conical chamber, a bobbin, with its spindle, rises automatically as it fills with yarn, and when filled it raises its spindle clear of its wharve, and thus stops automatically.