US394106A

US394106A - Phonograph-reproducer

Info

Publication number: US394106A
Authority: US
Publication date: 1888-12-04
Anticipated expiration: 1905-12-04

Description

(Model.)

T. A. EDISON.

PHONOGRAPH REPRODUGER.

No. 394,106. Patented Dec. 4, 1888..

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UNiTEn STATES PATENT OEEICE.

THOMAS A. EDISON, OF LLEVELLYN PARK, NEV JERSEY, ASSIGNOR TO THE EDISON PHONOGRAPH COMPANY, OF NE\V JERSEY.

PHONOGRAPH-REPRODUCER.

SPECIFICATION forming part of Letters Patent No. 394,106, dated December 4, 1888.

Original application tiled November 26, 1887, Serial No. 256,189. Divided and this application tiled March 2, 1888. Serial No. 265,888. (Modelt) To all whom it may concern.-

Be it known that I, THOMAS A. EDISON, a citizen ot' the United States, and a resident of Llewellyn Park, in the county of Essex and State of New Jersey, have invented a certain new and nset'ul Improvement in Phonograph- Reproducers, (Case No. Tol, division ol Case No. 74h) ot which the following is a specilicati on The ol'ijeet I have in view is to produce an efficient reproducii'ig-instrument l'or phonographs; and my invention consists in the several novel features and comli inations, as fully hereinafter explained, and pointed out by the claims.

In the accompanying drawings, Vforming a part hereof, Figure] Vis a bottom or rear view ot' the reprinlucer on an enlarged scale, and Fig. 2 a seetioiial view of' the same.

O is a metal plate forming the body of the reproducer. It has an opening, n, passing centrally through it, to which the listeningtube ol" the phonograph is applied. The plate O is ria-essed at its back, and has stretched across it a diaphragm, O', which is preferably a thin animal membrane. This diaphragm is secured in place by a ring, n', which is secured to the back ol" the plate O, while the diaphragm is stretclnld by another ring, uwhieh has a neck screwing into the opening u ot the plate, and is capable ot' being turned by a tool, so as to stretch the diaphragm O more or less. To one edge of the ring n is secured a line spring-wire, u3,whieh is long enough to reach t" rom the point where it is secured to the center otl the i'liaphragm, and has its inner end turned downwardly, as shown, to lollow the spiral line ot' indentations upon the phonogram. The inner end ot' this s1ning-wire fui is attached to the center ot' the dialihragm by a strip, ut, of rubber. The tendency ot the spring-wire is to bend away from the diaphragm, so that it strains the small rubber strip n4 and places the diaphragm under an initial tension. The

movement ot' the point ol' the wire u* in reproducing is so slight that the strain is never wholly removed from the rubber strip ut, and hence the diaphragm always under tension, which tends to draw it outwardly at the center. This makes the instrument exceedingly sensitive and capable of reproducing sounds accurately. The end ot the wire n3 being rounded and burnished, it will not obl iterate the phonog am-record, even though that record is made in quite soft niaterial.

I have found that by connecting the reproducing-point with the diaphragm by a strip ot' elastic material-such as rubber held under tensionthe proper wave motion is transmitted to the dialiihragm, but the scratching noises which seem to require molecular transmission are largely obliterated.

lVhat I claim isl. A phonograph-reprodueer having, in coinbination,a diaphragm and a reproducing-point connected with the diaphragm by a strained elastic strip, substantially as set forth.

2. A phonographreprodneer having, in combination, a diaphragm and reproducingpoint, a spring tending to'throw the reprodueing-Iiioii'it away from the diaphragm, and an elastic strip connecting the point with the diaphragm, wherelrv a spring-tension will always exist between the point and the diaphragm, substantially as set forth.

3. A phonograph relnoducer having, in combination, a diaphragm and a spring-wire i secured at its outer end and projecting toward the eenterotl the diaphragm and turned to t'orm a reproducing-point, said spring-wire tending to spring away l'rom the diapln'agm, and a strip ot iinlia-rubber connecting the end ot' the spring-wire to the center of the diaphragm, substantially as set lorth.

l. A phonograph reprodueer having, in ctnnbination, a diaphragm of animal membrane, a reproduci11g-point, a spring tending to throw the reproducing-point away from the diaphragm, and an elastic strip connecting said point with the center of the diaphragm, substantially as set forth.

5, A phonograph reprodnoer having, in This speciioaion Signed and witnessed this combination, a diaphragm of animal inonl- 20th day of February, i888. brano, a ring` for stretching such diaphragm, 1

a reproducing' point', a spring` tending to THOS. A. EDISON. 5 throw the reproducing-point away from the diaphragm, and an elastic strip Connecting XVitnesSes:

said reproducing-point with the diaphragm, XVILLIAM PELZER,

substantially as set forth. E. C. ROWLAND.