In the older machine, the utmost speed at which the fellers or hammers can work is sixty blows per minute ; with this new machine, the hammers work at 420 blows per minute. An elastic blow is obtained by suspending the hammer in a leather strap, attached to a semicircular steel spring, which receives its up and down motion from a crank. Fig. 366 gives a section of the machine, with another arrangement for-supporting the beams of cloth. C is a wooden hammer, backed by an iron block, the whole being suspended in leather thongs. D is a guide to prevent the block from oscillating to the side. At E is the crank shaft ; A A are the beams of cloth, and F F is the framework of the whole machine. It musl be remarked, however, that these machines have not been able entirely to supersede the old kind. Experience has shown that they cannot produce the water mark, though they serve admirably for a preparatory beetling, thus saving time. This machine rough-finishes for five machines of the older kind, and for this purpose takes the place of seven of the latter. The whole process of beetling may last from a few minutes to several hours, according to the degree of finish required.
Folding.—This is the last process, by which the finished pieces are made up into folds of a uniform length, generally about a yard. Formerly this was done by girls, hooking one selvage of the piece backwards and forwards on to straight or only slightly curved steel books fixed on a wooden frame, or against a wall. One of the hooks was moveable, so that it could be fixed to suit any length of fold.
Figs. 367 and 368 represent the modern folding machine of Messrs. Hacking, Bury, in general use. Fig. 367 shows a perfect machine, with all the working parts. The motion is imparted to the machine by means of pulleys fixed on the first motion shaft A ; thence it is communicated to the crank shaft by the spur wheels B. At each end of the crank shaft, are cranks (one of which is shown at C), which give an o,,eillating motion to the side arms D, through the connecting piece E. At the top of the side arms D, there are carried knives or folding blades bb, which are for the purpose of laying the folds alternately under the holding rails g' 92. The semicircular table F is made to press upwards by means of counterpoise weights G against the holding rails gl g2, and so securely holds the cloth laid by the folding blades b b. To make the hold on the cloth more secure, the holding rails are generally covered with pin-pointed cards or with corrugated indiarubber. When the piece is folded, the foot lever is depressed ; this causes the table F to descend, and relieves the cloth from the holding rails gl 92, so that the folded piece can be removed.
Such is a rough general description of the ordinary movements of this machine. The whole is, however, so complicated and ingenious that a reference to some of the special movements is necessary. The swivelling arm a, which determines the swivel of the knives or plaiter b, is worked
by a cam c, placed upon the crank-shaft d, thus communicating (by means of levers e and f) the necessary amount of swivel to the knives without any alteration, at whatever length of plait the machine may be required to work. The altering of the position of the card-rails is effected as follows :—The card-rail brackets g' g2 are extended, by means of the levers h' to the rocker shaft i. In the levers it' h2, are made the slots ki k2, in which work the studs /' /2; these, being actuated by the right and left hand worm-shaft m, cause the levers h' A', bearing the card-rail brackets, to approach or recede from one another, as the handle n, upon the end of the worm-shaft m is turned round, either from left to right or vice versii. This motion is communicated by means of the bevel vvheels o to the opposite side of the machine, so that by turning the handle n the card rails are set parallel at any required diste.nce, with the greatest ease. The top of the framing is marked in half inches, and a finger is attached to the card-rail bracket, so that the handle n must be turned round nntil the finger points at the required fig-ure ; the cards are then in a position to work. The regulation of the crank, to give the required sweep to the knives, is rendered very simple. On the square-ended shaft d, is placed a box key or handle, which, in being turned round, draws the crank arm towards or farther from its centre, by means of the bevel wheels p and the screw q; this motion is communicated also by the shaft d to the opposite side of the machine, so that by turning the handle on the end of the shaft d, the crank, which is also marked in half inches, is rapidly brought to the required point. Fig. 368 represents only such parts as are necessary to illustrate the special movement, to which reference will now be made. The object is to draw down the table F on which the cloth is being folded, at each side alternately, just as the folding knife b enters under the holding rails 9' or 92, and to let the table rise and secure the cloth immediately after the knife passes out. The knife thus passes under each folding rail without friction or wear, and the folded cloth is not pulled, rubbed, nor scratched. This is effected by means of the chains r and r', which are connected with the table, and are alternately drawn down by the cam and bowl y and z fixed on the crank shaft h, which, as they revolve, work against the curves t and t', and force them in opposite directions. The curves being con nected with the chains by the rods s and s', cause the table to be de pressed. The folded pieces are next re-folded into three by hand, pressed, and stamped ready for packing.