Blackwood's Magazine/Volume 1/Issue 2/Account of Mr Ruthven's Improved Printing Press
ACCOUNT OF MR RUTHVEN'S IMPROVED PRINTING PRESS.
As one of the objects of this Magazine is to disseminate useful knowledge, we cannot attain the end in view with better effect than by giving some account of a most important improvement in the mechanical part of printing, by Mr John Ruthven, printer, of this place. This very ingenious mechanician having diligently studied his profession for upwards of twenty years, observed that there were numerous defects in the construction of the printing presses commonly employed, the principle of which is unaltered from the time of the invention of printing. The excessive and dangerous labour occasioned to the workmen, and the very imperfect adaptation of the press to many purposes, were the most obvious defects; to remedy which, by any improvement of the original machine, Mr Ruthven found, after diligent study, to be quite impracticable;—he therefore resolved on attempting something new; and after much labour, he has succeeded in producing not only a highly useful press, but in giving a most beautiful application of a combination of levers, for the production of parallel motion, with a degree of power hitherto unequalled.
For the better understanding of the account we propose to give, it will be well to premise a few observations on the printing-press commonly used.
The screw has hitherto been the power employed to produce pressure, while the types were placed on a moveable carriage, which was moved, after the ink had been applied, under the surface for pressing. In consequence of this, the power has always been limited,—the radius of the lever which moves the screw being confined. It is also a consequence that not more than one half of a large sheet could be printed at one descent of the screw. A most serious evil results from this, especially in printing duodecimo, because the pressure necessarily is applied twice to the centre pages of each sheet, while it is applied only once to the other pages. To these disadvantages may be added, the difficulty of ascertaining and regulating the degree of pressure; the irregularity of the motion of the lever; the severe labour, and excessive exertion of the workman; the nice accuracy in placing the types under the centre;—there being no difference, in point of trouble and labour, in printing a card and a folio;—and the necessity for placing small work always in the same spot, which necessarily wears out one part sooner than the others. In obviating these defects, Mr Ruthven has completely succeeded;—and after giving some account of the construction of the new printing press, we shall point out the superior excellencies of it as briefly as possible.
The general appearance of the large press is well represented in fig. 1.; of which fig. 2. is a complete section. In this press the types are placed on a stationary coffin or tablet, P; the paper is put on in the usual manner on the tympan, a, (fig. 1.) and secured by the frisket, b. On turning over the tympans thus arranged, the platen, N (fig. 2.),—supported by the wheels, QQ,—is drawn over the coffin by the handle, U, till the lower parts of the screw bolts, M M, be fully secured in the clutches, L L (fig. 2.); the lever or handle, A, is then turned over in the front of the press till stopped, when it will be nearly in a horizontal position. It is then restored to its original situation, the platen pushed back, the tympans raised, and the printing is completed. The mode in which this movement is produced is concealed by the check, R.
The action which takes place in the above-described process will be best understood by a reference to, and examination of, the section, fig. 2. The platen is, in this, represented in its proper situation over the types. The parts of the external structure have been already sufficiently explained; it only remains to point out those which are exposed in the section. Beneath the tablet, P, and immediately behind the check, R, are the levers, I I, having their fulcra at K K; to which are attached the clutches, L L, communicating as above-mentioned with M M; the motion to which is given by the bolt, H, forming a point of union between the levers, I I. When their ends are depressed by means of the crank, E G F, which is moved by the handle, A, communicating to the crank, B C, and the connecting rod, D, the platen or upper surface, N, is forcibly drawn down upon the types.
Fig. 2
| Fig. 3. | Fig. 4. |
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To maintain the relative position of the several levers, the balance-weight, S, is applied. T T T is the framework supporting the whole of the machinery.
Such is as minute an account of Mr Ruthven's printing press as is necessary for general information. It is here proper to state some of the points of superiority which it has, very decidedly, over all other contrivances of the same kind. These may be very briefly detailed, as we have already pointed out the most glaring defects which first solicited Mr Ruthven's attention.—1st, In the new patent press the types remain stationary. 2d, The platen is the size of the whole sheet, 3d, Time is saved by its being brought over from the side. 4th, There is nearly half an inch between the tympans and the platen while passing over the types, by which all blurring is avoided. 5th, Any degree of pressure (from an ounce to twenty tons) may be correctly and uniformly given at pleasure. 6th, The platen being drawn down by the two ends, and the resistance sustained against the under surface of the tablet, affords the most complete and uniform security to all the parts; while, contrary to every other example known to us of the application of pressure, the frame is wholly independent of, and unaffected by, the force employed. 7th, As complete parallelism between the two surfaces (viz. of the platen and coffin) is maintained by means of the two screws, O O, so a small piece of work may be done at either end without a supporting block at the opposite extremity. 8th, This press being entirely unattached, requires no levelling or staying; and one for demy royal requires a space of only forty-two inches square. 9th, The motions of the pressmen, though less severe, are sufficiently similar to enable him, in the course of one or two hours, to work with equal facility as at the common press. 10th, The principles above described are equally applicable to presses of all sizes. Fig. 3. represents one of the size of a cubic foot, which is capable of printing off an octavo page with greater celerity than a larger press, and may be worked on a common table without being fixed. The advantages of foolscap-presses of this construction will be found very important.
An ingenious application of the principles of this press has been made to copying manuscripts; for that purpose (although it may with perfect effect be done with the small printing presses) Mr Ruthven has contrived the press represented in fig. 4. which is made without the printing apparatus, and having, instead of the clutches, permament pillars to connect the upper surface with the levers. The parallelism of the two surfaces is regulated by two graduated scales and indices at each end, as may be seen in the annexed figure.
We are persuaded, that when, in addition to the excellencies already described, the extreme simplicity of the new patent press, and its little liability to derangement, are taken into consideration, it will in a short time supersede every other printing machinery that has hitherto been in use.