Roll (machine)

“ When the two rolls are moved towards each other, the friction on the board causes the hammer to rise; and when again separated the hammer will fall. The back roll is keyed to a shaft, on each end of which is a driving-pulley; and thus by the use of two pulleys on the same shaft, equal wear comes on the bearings in which it revolves. The front roll turns freely on its shaft, and is driven by the back roll being geared to it. To secure to the gears both strength and durability, they are made with wide faces, are geared at both ends, and the teeth are of peculiar shape. ”

“ For a single-acting machine the wires should be loose, so that they can roll with the cords; but for a double-acting machine this would be of no advantage, as a portion of the cords are falling when the remainder are rising. If the machine is very wide, [78] or has to be set forward or back on the loom, there should be cross rollers of hard wood above the wires, at right angles to them, to prevent the bottoms of the hooks from being drawn either backwards or forwards, which might push their heads on or off the griffe knives. ”

“ This chain is operated by the vertical shaft j, having a pulley for belt power at k.
As each die approaches the rollers, a shoe (cut to length, creased, and punched as already described) is placed on it, and on reaching the rolls the shoe is pressed into form on the die by the rolls, the bottom roll serving as a rolling bed so as to reduce the friction that would be due to a sliding motion on the bottom of the die. The top roll c, which presses the shoe into the die is driven by power.
Fig. ”

“ As a result, the surface produced depends for its truth upon the truth of the tool-guiding ways. In the Poole lathe, however, while guideways are necessarily employed to guide the emery wheels in as straight a line as is possible, by means of such guides, the roll [I-197] itself is employed as a corrective agent to eliminate whatever errors may exist in the guide. The rolls come to this machine turned (in the lathe Fig. 730) , and with their journals ground true (on dead centres) . ”

“ The under cutter is adjusted for depth of cut by turning hand wheel a′, which moves the screw u′. The rolls are raised and lowered by turning the shaft at p (Fig. 3176) .
In feeding two boards through the machine, one thicker than the other, that end of the roll that passes over the thick board can raise up without taking the pressure off the thin one at the other end of the roll. This raising mechanism is shown in Fig. 3179. The bevel gear c works over a ball joint q′. The shoulder b′ on the screw a′ works on the under side of the ball q′. ”

“ On every side are fresh wonders. Here is an immense rolling machine, fed with plates 27 feet wide, which bends the 1 1 / 8 -inch thick metal as if it were so much pastry; or turns over the edges neatly at the command of a 50 h.p. motor. There we have an electric plate-planer scraping the surface of a sheet half the length of a cricket pitch. As soon as a stroke is finished the bed reverses automatically, while the tool turns over to offer its edge to the metal approaching from the other side. ”

“ The rolling machines through which the ingots are passed are adjustable, the space between the rollers being governed by the operator. About two hundred ingots are run through per hour on each pair of rollers.
When the rolling is completed the strip of metal is about six feet long. As it is impossible to roll perfectly true, it is necessary to “draw” these strips, after being softened by annealing. The drawing benches resemble long tables, with a bench on either side, at one end of which is an iron box secured to the table. In this are fastened two perpendicular steel cylinders. ”

“ The upright engine, on the right, of one hundred and sixty horse power, supplies the motive force to the rolling machines, four in number. Those on the left, are massive and substantial in their frame-work, with rollers of steel, polished by service in reducing the ingots to planchets for coining. The first process or rolling is termed breaking down; after that it requires to be passed through the machine until it is reduced to the required thinness—ten times if gold, eight if silver, being annealed in the intervals to prevent breaking. ”

“ The detaching portion of the mechanism consists of the three rollers Q S and T, but the fluted segment N1 also aids in this portion of the work. The roller S is known as the “steel detaching” roller, and receives an intermittent motion in both directions from a cam at the end of the machine. The roller Q is known as the “top detaching” or the “leather” roller, and is covered with leather, being borne by levers R, to which the necessary oscillation is given by a cam and the connecting rod R1. ”

“ The printing roller C is the only part of the machine directly connected with the motor or main drive of the works through the cog-wheel on its axlethe “ mandril ”-all the other parts deriving their motion from it, either by friction as in the case of the cylinder or by a spur wheel as in that of the colour-furnishing roller. ”

“ On these machines the fabric is not held down by weights, hanging thereon, as in the hand machines, but by what is called a take-up roller which has means provided for adjustment to keep the desired strain on the fabric at all times. The weights which are in plain view are to hold the fabric up to and in close contact with the take-up roller through a frame with a small roller on the fabric side of the frame and the weights on the outside, which work on the lever and fulcrum principle.
An automatic machine must have a pattern chain of some kind or character to operate its automatic functions. ”

“ 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. ”

“ 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. ”

“ 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 ”

“ 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. ”

“ 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. ”

“ 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. ”

“ 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. ”

“ On the top of the detaching roller is a large steel fluted roller carried at each end by a small arm called a "horse tail." In the original machine this roller simply kept its place upon the detaching roller by its weight, and when the machine came to be run at high speeds it was found that owing to its lightness the contact thus obtained was not reliable, the flutes or ribs of the roller slipping upon those of the detaching roller, which for good work is undesirable. ”

“ The rollers and cylinders are then put in motion by wheel-work moved by a horse, water, or any other impulsive power; the wool, &c. is drawn forward, and extended, during its passage, into a thread or sliver; which, on being submitted to the adtion of a similar machine, but of different dimensions, is spun into thread of various degrees of fineness: after the yarn has thus passed beneath the rollers, it falls into canisters suspended below, for its reception.—A minute specification of this useful machinery is inserted in the 16th vol. ”

“ The frame is necessarily long, usually about 15 feet, and the width of the machine about 5 feet, these dimensions depending upon the size of the sheet to be printed. The table or carriage is double, containing two beds for the two formes of type, to impress the two sides of the paper, and two distributing tables for the ink. At each end is a complete roller apparatus, consisting of duct, duct roller, vibrator, and wavers. Close to the large cylinders on each side are the inking rollers. The table has a reciprocating motion, as in a single-cylinder machine. ”

“ 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 live spindle is carried in and is capable of motion in a sleeve, the latter having upon it a worm-wheel, operated by a worm, so that it can be moved through any given part of a circle, and has index holes upon its face to determine when the wheel has been moved to the required amount.
For work that is too large to be operated upon in the class of shaping machine shown in Fig. 1506, and yet can be more conveniently shaped than planed, a class of machine is employed in which the tool-carrying slide is fed to the work, which is chucked to a fixed table or to two tables. ”

“ All shapes and sizes of bar iron used in blacksmithing may be produced in this manner. Rolling machines are known as two, three, and four high, meaning that they are provided with that number of rolls, one above the other. Universal rolling machines have two pairs of rolls in one machine ”

“ When the metal has solidified, 314the core is simply lifted off, and the cast is then taken out, in the form of a semi-cylinder, the internal surface of which has exactly the diameter of the external surface of the roller of the machine on which it is to be placed, in company with another semi-cylindrical plate, so that the two together encircle half the length of the roller, and when another pair of semi-cylinders have been fixed on the other part of the roller, the whole matter of one side of the newspaper sheet, usually four pages, is ready for printing. ”

“ The edges of the rollers come near together, leaving sufficient space for the thread of the worm to fit between any two contiguous rollers. The pitch line of the screw thread forms an arc of a circle, whose centre coincides with that of the wheel, therefore the thread will always bear fairly against the rollers and maintain rolling contact therewith during the whole of the time each roller is in gear, and by turning the screw in either direction the wheel will rotate. ”

“ 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. ”

“ It is sometimes the practice to grind the leather covered rollers so as to remove any flats formed during working. Messrs. John Hetherington and Sons make a machine for this purpose. By it the rollers, while held in suitable bearings, are subjected to the action of a revolving grinding disc, covered with glass paper, which traverses the whole surface of the roller and grinds it up perfectly true. The rollers so produced are quite cylindrical, and a large number of the machines are in use. ”