The talking machine world (Jan-Dec 1913)

52 THE TALKING MACHINE WORLD. engaged at any point in the reproduction of a record by merely lowering the reproducing stylus into tracking position upon a record or raising it therefrom. This invention also comprises an improved construction of a talking machine enclosed within a cabinet in which the sound amplifying horn is carried by the hinged cover of the cabinet. Figure 1 represents a plan view of a reproducing talking machine embodying the invention. Fig. 2 represents a horizontal cross section taken on line 2—2 of Fig. 3. Fig. 3 represents a central vertical cross-section through the talking machine shown in Fig. 1, certain parts being shown in side elevation. Fig. 4 is an enlarged detail perspective view of certain parts shown in Figs. 2 and 3. Fig 5 is a vertical cross-section of a talking machine similar to that shown in Fig. 3, provided with a hinged JUo. 6 , cover carrying the amplifyi n g horn, certain parts being shown in side elevation. Fig. 6 is a front view of the machine and cabinet shown in Fig. 5. Fig. 7 is a plan view of the same, and Fig 8 is a side elevation, the cover being shown in raised position. Phonograph. Newman H. Holland, West Orange, N. J., assignor to Thos. A. Edison, Inc., West Orange, N. J. Patent No. 1,049,237. This invention relates to phonographs and more particularly to those adapted for use for commercial purposes, although obviously the invention may be used in connection with other types of phonographs. , The principal object of the invention is to provide an improved recorder and reproducer support, perferably carried by the traveling carriage or carrier arm, and provided with means for operating the same so as to bring either the recorder or reproducer into operative position with respect to the record surface, or for bringing the parts into such" position that both the recording and reproducing styli are entirely clear of the record surface so that the record cylinder can be removed from or placed on its support without contacting with either of said styli, and the traveling carriage can be shifted without injury to either the record or the reproducer and recorder. A sound conveying tube to which an amplifying horn or other sound conveyor may be applied is provided, and the recorder and reproducer are connected with this tube in such a way that when the recorder is in operative position the interior thereof is in communication with the said tube, while the interior of the reproducer is entirely out of communication therewith, and vice versa. Means are also provided for rendering inoperative the mechanism for feedi n g the reproducer and recorder across the record surface when the support is being adjusted to place one stylus in operative position and remove the other therefrom. Figure 1 is a central vertical sectional view of one embodiment of this invention, some of the parts being shown in elevation. Fig. 2 is a plan view thereof. Disc Record and the Production Thereof. Victor H. Emerson, New York, assignor to the American Graphophone 'Co., Bridgeport, Conn. Patent No. 1,050,932. This invention relates to the production of commercial sound records of the disc form. Such records are now commonly made of a plastic material composed largely of earthy material and shellac. The surface of such records is, on account of the extremely hard particles present in the earthy material, comparable to a very fine emery wheel, and rapidly wears the point of the reproducing stylus. For this reason it is the practice to use very cheap reproducing needles, employing a fresh needle for each reproduction. Notwithstanding the use of very soft reproducing needles, records of this sort are comparatively shortlived, and the quality thereof begins to show signs of deterioration after a relatively small number of reproductions. This is due to the fact that the surface, though quite hard, presents numerous very fine points against which the stylus engages and changes the form of the undulations. The object of the present invention is to produce records which will endure a greater number of reproductions without deterioration of quality, and having a surface which will not abrade the stylus, so that a permanent reproducing point may be employed therewith. It also aims to effect economy in production of the record, and to give a smoother reproduction of the recorded sounds free from scraping noises. In the compositions now in use the shellac is needed in order to give the sunface of the record a "glazed'' character. The composition without shellac would be utterly unsuited.to the purpose; and, as already stated, even where a large proportion of shellac is used the surface is characterized by the presence of numerous abrading particles. No satisfactory substitute for shellac for this purpose has yet been found, and its greatly increased cost has added largely to that of the sound records. The inventor states that a record pressed in a continuous surface of shellac, while not so hard as that of the ordinary composition, is so smooth that a reproducing point will rub over the same with inappreciable friction, and with very slight wear to either record or point. For the same reason the scratching noises heard in the reproduction of ordinary sound recods are much diminished. The principle of the present invention is, therefore, the production of a sound record impressed in a continuous film of shellac to a minimum. The body of the sound record may be made of any suitable and cheap inferior stock which in itself may he unsuitable for a smooth record surface, but is capable of being rendered plastic, for example, by the earth compounds now in use, with an ordinary binding agent instead of shellac. In carrying out the principle of the invention difficulty has arisen in obtaining a filmy, smooth surface, free from the gritty particles liable to be present in the stock, but this result has now been accomplished by employing a thin separator — preferably a sheet of fibrous material, as paper — between the shellac surface and the plastic stock composing the body of the tablet. Another difficulty has arisen in impressing the matrix into this shellac surface, in that air would be entrapped between the shellac surface and the matrix surface, resulting in a bad impression of the undulating record lines. This difficulty has now been overcome by applying the plastic stock to the rear surface of the sheet in the form of a lump placed in the center of the disc, the effect of which is that, as pressure is applied, the lump of stock spreads outwardly from the center whereby the air is driven out from between the matrix and the tablet. In practising the invention it has been found that linen paper of good quality and about five one-thousandths of an inch in thickness will answer the purpose in a satisfactory manner. A sheet of such paper may be coated by dipping into an alcoholic solution of shellac, or the latter may be applied with a brush, or otherwise. In this way the paper acts as a carrier for the shellac (permitting) the use of minimum quantity of the latter), as well as a separator from the material employed for the body of the tablet. To form the sound record the paper so treated is laid on the T T Fig.l Fig. 2 Fig.3 Fig* Fig 6 warmed matrix and placed as usual in a suitable press ; the stock, in the form of an approximately globular lump, is laid on the paper sheet at the center of the matrix, and pressure is then applied in the usual way. The stock is applied in a plastic state, being softened at a temperature of about 190 deg. F. A solid and strong tablet results, the union of the several parts thereof not being affected by expansion and contraction due to changes of temperature. Although reference has been made above solely to shellac, which gives the best results of any material thus far tried for the purpose, it is obvious that other gums, celluloid or like materials may be employed in the same way. When shellac is used, it is preferable, after drying the sheet, to dip it in a very thin solution of celluloid, which protects the shellac and prevents it from sticking to the hot matrix. In said drawings, Figures 1 to 6, inclusive, are side elevations. Fig. 1 shows a sheet of paper with a film of shellac thereon ; Fig. 2 is the same as Fig. 1 with the addition of a celluloid coat on the shellac ; Fig. 3 illustrates a matrix with a shellac-coated surface against the matrix ; Fig. 4 is the same as Fig. 3 with the addition of a mass of inferior plastic composition placed in the center thereof; Fig. 5 shows the plastic composition in the act of being pressed out or flattened by a press and spreading from the center outward ; Fig. 6 shows the plastic composition spread over the back of the sheet of paper, and the press in the act of forcibly pressing the plastic material, the paper sheet and the shellac together, and impressing the latter into the face of the matrix. Fig. 7 is a perspective view of a tablet with the plastic material, the sheet of paper, the shellac and the celluloid united together into a complete record tablet under the action of the heat and pressure in the press. Sound Box for Gramophones. Ernest de la Rue, London, Eng. Patent No. 1,051,489. This invention relates to what are known as "edge mounted" diaphragms, that is to say, diaphragms which are not nipped between two surfaces but are secured by their edges being pressed against elastic surfaces. With some diaphragms, and especially mica diaphragms, great difficulty is expe'2 rienced in getting the dia phragm into place without either cockling or injuring it. According to this invention the elastic surface is carried by the semi-circular halves of a split ring, and after the diaphragm has been put into place the ends of the halves of the split ring are drawn together by screws. Figure 1 is a plan and Fig. 2 a section on the line 2 — 2 Fig. 1. Sound Recording Apparatus. Fordoonjee Dorajee Pudumjee, Bombay Presidency, India. Patent No. 1,051,513. The invention refers to an improved method and apparatus for recording sound and is particularly applicable to the manufacture of gramophone records. The method as at present used consists in cutting or engraving the vibrations produced by sound on a rotating disc of specially prepared hard wax by means of a sharp point or cutting edge attached in a particular way to a membrane which vibrates in unison with the sound produced in front of it. The vibrations are engraved parallel to the surface of the disc in the shape of a spiral, and the engraving thus forms the original record from which duplicates are made by pressing ebonite or similar composition discs on a matrix which is made from the original wax record by the process of electrotyping. The principal disadvantages of the process as at present worked reside in the fact that considerable resistance is offered to the engraving point by the substance engraved, so that the vi(Continued on page 53.) Tig. 2.