Roller (machine)

“ When motion is given to the worm then rotation is produced in the roller wheel at a rate proportionable to the pitch of worm and diameter of wheel respectively.
In the arrangement for transmitting rectilinear motion from a screw, rollers may be employed whose axes are inclined to the axis of the driving screw, or else at right angles to or parallel to the same. When separate rollers are employed with inclined axes, or axes at right angles with that of the main driving screw, each thread in gear touches a roller at one part only ”

“ In its simplest form the roller-printing machine consists of a strong cast iron cylinder mounted in adjustable bearings capable of sliding up and down slots in the sides of the rigid iron framework. Beneath this cylinder the engraved copper roller rests in stationary bearings and is supplied with colour from a wooden roller which revolves in a colour-box below it. ”

“ In this case the head would be said to be one of three “deliveries,” and a machine is usually described as being one of so many heads of a certain number of deliveries. It will be easily understood that the top rollers are not positively driven, but derive their motion by frictional surface contact with the lower set. The top rollers are accurately turned, and are usually covered with a specially-prepared soft leather, formed into a sheath, which can be drawn over the boss of the roller. ”

“ If by any chance the machine should be overcharged, that is, if too many rags are passing through the rollers, the top fluted roller is raised up, and the rags are simply carried, or thrown by the swift, over into a box on the opposite side of the machine without being subjected to the tearing process. ”

“ For this purpose the rollers are revolved by being brought into frictional contact with a rotating cylinder. The most complete machine for this purpose is shown in Fig. 219. The rollers are held in arms B B on the cylinder A, the bearings or steps in the arms being specially constructed, so as to provide a very thin surface to sustain the roller. The ends of the leather being cemented, they are turned over by means of a rod or bar, and are thus perfectly secured. A fan F is placed under the hood of the machine, and takes away any fumes produced by the process of ending. ”

“ The slips of metal to be operated on by the drawing machine, are first rendered thinner at one end, that they may be introduced between the dies, and also between the jaws of the pincers. This thinning of the ends is effected by another machine, consisting of a small pair of rollers, mounted in an iron frame, similar to a rolling-mill. The upper roller is cylindrical, but the lower is formed with 3 flat sides, leaving merely portions of the cylinder entire, between these flat sides. ”

“ It appears, then, that the larger the roller the quicker the forward motion and the slower the return one, which is advantageous, because the object is to move the roller out quickly and close it slowly, so that under a quick speed the cam shall not run away from the roller as it is apt to do in the absence of a return or backing cam, which consists of a separate cam for moving the roller on its return stroke, thus dispensing with the use of springs or weights to keep the roller upon the cam and making the motion positive. ”

“ Above this roller-beam, is the creel-ring N O, which (either in one or two rows) receives the sixty roving bobbins that supply the sixty spindles, of which the Machine is composed: and whose threads pass under the eight sets of rollers—one thread being suppressed in each of the heads—1, 4, 5, 8, on account of the columns. (This, at least, is the arrangement I prefer; but some of the Machines have been made with eight threads in all the compartments.) ”

“ Pegged rollers were the earliest form for this purpose, and later corrugated rollers and power-worked hammers were employed. Hundreds of hides could be softened daily by these means.
Then came ingenious machines to take the place of the previous operations of the hand tools,—the fleshing machine, in one form of which the hides are placed on a curved bed, and the fleshy parts scraped off or removed by revolving glass blades, or by curved teeth of steel and wood in a roller under which a table is given a to-and-fro movement ”

“ The rollers and clearers are ground after removal from their places in the machine. A machine of which Fig. 110 is a perspective view is employed for this purpose, this being the type made by Messrs. Dronsfield Brothers, who have specially devoted themselves to this class of machines. The machine consists of a frame which has bearings formed, in which the shaft of the grinding roller revolves. Affixed to the lower portion of the frame is a counter shaft from pulleys, on which the emery roller is driven at a speed of 300 revolutions per minute. ”

“ In making a cam of this form, the body of the cam is covered by a sleeve. The groove is cut through the sleeve and into the body, and is made wider than the diameter of the roller. When the rollers are in place on the spindle or journal, the sleeve is pushed forward, or rather endways, and fastened by a set-screw. This gives the desired bearing on both sides of the groove, while each roller touches one side only of the groove. ”

“ Another type of machine termed the three pair roller jute opener is illustrated in fig. 3. The layers from the different bales are laid upon the feed cloth which carries them up to the rollers, between which the layers are crushed and partly separated. The proximity of the weighted roller or rollers to the fixed ones depends upon the thickness of material passing through the machine. The fibre is delivered by what is called the delivery cloth, and the batcher usually selects small streaks of about 11⁄2 ℔ to 2 ℔ weight each and passes them on to the attendant or feeder of the softening machine. ”

“ Further rigidity is achieved by means of hand-forged lag screws. The arch of the frame is birch and the arch arm maple. The 14-inch doffer roller is made of chestnut. [17] The iron shafts are square and turned down at the bearings. The worker rollers are fitted with sprockets and turned by a hand-forged chain. The comb plate, stamped "Standring," is hand filed, and is undoubtedly one of those made before the "teeth-cutting machine" was smuggled from England, for although one-third of the plate is quite regular, the size and pitch of the teeth in the remaining two-thirds are irregular. ”

“ The general description and history of the machine just given will convey a fairly accurate idea of its development, and the details of the machine can now be dealt with. The drawing rollers being common to all spinning machines no further description than that given need be furnished; but a reference to Fig. 188 will show that the roller stands, the thread board mechanism, and the relation of the spindle and ring are the chief points requiring explanation. ”

“ The fabric or goods to be operated upon being first wound tightly upon a roller, that roller is to be mounted upon an axle or pivot, bearing in arms or brackets at the back of the machine, as shown at D. From this roller the fabric a a a a is conducted between tension rails, and passed under the bed cylinder or paper bowl E, and from thence proceeds over a carrier roller F, and over steam boxes not shown in the drawing, or it may be conducted into a hot room, for the purpose of drying the colours. ”

“ The copper roller is mounted on a stout steel axle, at one end of which a cog-wheel is fixed to gear with the driving wheel of the machine, and at the other end a smaller cog-wheel to drive the colour-furnish in roller. The cast iron pressure cylinder is wrapped with several thicknesses of a special material made of wool and cotton—lapping—the object of which is to provide the elasticity necessary to enable it to properly force the cloth to be printed into the lines of engraving. ”

“ Six or eight slivers (C) are put up to each delivery and drawn down into one by causing succeeding lines of rollers (A, B) to move at an accelerated speed; the front one revolving about six or eight times faster than the back one. On leaving the front roller the sliver is conducted to a trumpet-shaped tube (D) , thence between a pair of calender rollers (E) , and, finally, through a diagonal passage in a plate (F) ; the latter coils the sliver into a rotating can (G) . Back and front devices are provided to arrest motion in this machine when a sliver fails. ”

“ The driven part is made of hardened silver steel, and there are means of taking up all slack arising from wear directly it becomes manifest. Instead of the cross being struck by a pin on the driving wheel, the latter carries a roller which picks up the slotted wheel without jar or noise. The mechanism is kept cool by running in an enclosed oil bath, which tends to reduce the wear and tear to a minimum, while at the same time the machine is light and easy running, a feature which appeals to the operator. ”

“ Douglas Fraser & Sons, Ltd., Arbroath, are seen distinctly in Fig. 17, and the can or cans into which the slivers are ultimately delivered are placed immediately below one or more sections of these rollers and in the foreground of the illustration. The large pressing rollers, which are in contact with the drawing roller, occupy the highest position in the machine and near the centre of same. Between these rollers and the retaining rollers are situated the above-mentioned fallers with their complements of gill pins, forming, so to speak, a field of pins. ”

“ As the roller A revolves, it brings the skins in contact with a grinding roller B, covered with sand or glass paper. In this way the leather is ground down to one thickness throughout the strip, and the chance of unevenness in the roller is thus diminished. A fan is fixed to draw away the dust and deposit it in a suitable receptacle. After the strips are so ground, they are passed to a splicing machine—that is, a machine in which they are cut to the necessary length to form a sheath. ”

“ If desired, the lifting off motion is attached to both running and finishing sides, and also the roller partly seen on the left hand for running the hanks through the size. The machine we saw was doing about 600 bundles per day at running and at finishing, but the makers claim the production with a double machine to be at the rate of about 36 10 lb. ”

“ By placing the tool at different distances from the revolving centre while leaving the roller at the same distance, the size of the hole could be diminished or increased to any desired scale. A machine for planing the very long plates required in the lattice girders is shown in Figs. ”

“ The distance between the centres of the rollers is regulated by screws, furnished with wheels on their upper ends, similar to what is seen in the drawing dies at C. The two rollers have pinions on their axes, which make them revolve together; they are set in motion by an endless strap passing round a drum, upon whose axis is a pinion working into the teeth of a wheel fixed upon the axis of the lower roller. ”

“ The rollers move along with a velocity equal to one half the relative velocity of the surfaces. This way of reducing frictional resistance has been applied to all kinds of mechanical contrivances, including bearings for shafts, railway axle boxes, and axle boxes for tramcars. An example of a roller bearing for a line shaft is illustrated in figs. 8 and 9. The main casting, A, and cap, C, bolted together, form a spherical seating for the part of the bearing E corresponding to the brasses in a bearing of the usual type. ”

“ Because the road is a circular one that travels with the load we can line it with rollers throughout its length, and the load will never lack for rollers to [206] roll upon. Thus we have the roller bearing which is so widely used in modern vehicles. Ball bearings operate on the same principle except that the balls furnish less contacting surface and are not so suitable for supporting heavy loads, as are rollers. Sliding friction is almost completely eliminated and unless heavily loaded a wheel on ball bearings will not heat even when the bearings are not lubricated. ”

“ The rollers are made of hard tool steel, and the surfaces of the journal and bearing between which they roll are hardened.
Two rings of balls may be used instead of a single ring of rollers, and the kind of ball bearing thus obtained is in general use principally in connexion with bicycles and motor cars (see Bicycle) . In ball bearings the load is concentrated at a few points, the points where the balls touch the race, and in the roller bearing at a few lines, the lines of contact between the rollers and the surfaces of the journal and bearing ”

“ Many people call road rollers “steam rollers.” That’s because the first ones really were driven by steam engines. Men have a lot less fuss and bother with a modern Diesel-engined tandem. There’s no need to start the fire or shovel coal to keep steam up. You can still see some steam rollers at work, though, because they are strong machines that last a long time. But when one wears out, it is replaced with a modern roller.
After the roller finished smoothing all the asphalt down, Charlie’s road was ready for traffic, but the job still wasn’t quite done. ”

“ A white-hot ingot of steel is presented to a pair of powerful rollers, which grip the steel, and send it through at the other side both compressed and elongated. Tremendous power is required to meet the sudden demand on the machine at the critical moment. To obtain this power an engine of stupendous [57] proportions is sometimes attached directly to the rollers, but more frequently an engine of rather less horse-power will be used, the might of this engine being applied to giving rapid rotation to an immense fly-wheel, which may thus be regarded as a reservoir full of energy. ”