US401227A - George thomas - Google Patents

Description

N" me G THOMAS MECHANICAL TELEPHONE.

Patented Apr. 9,1889.

fill/11111 No. 401,227.r

Y @gvd fall @tm UNITED STATES PATENT EEICE.

GEORGE THOMAS, or NEW YORK, N. Y., AssIeNOE or ONE-ritmo 'ro JOSEPH u. sfMrsoN, OE SAME rnlcE.

MECHANICAL TELEPHONE.

SPECIFICATION forming part of Letters Patent No. 401,227, dated April 9, 1889.

Application tiled October l5, 1388. Serial No. 288,137. (No model.)

.To al?, whom t may con/cern.'

Be it known that I, GEORGE THOMAS, of the city, county, and State of New York, have invented new and useful Improvements in Acoustic Telephones, which are fully set forth in the following' specification and accompanying drawings, in which- Figure l is a sectional view of myimproved telephone; Fig. 2, a side elevation of mouth Io and ear piece; Fig. 3, a sectional view ot diaplnagm-lmtton; Fig. 4, a plan of diaphragm;

Fig. 5, a perspective view of insulator for diaphragm.

This invention relates to acoustic telephones in which a line of wire `connects two vibrating diaphragms, either of which may receive or transmit sound, and its purpose is to transmit sound more clearly than has been attained by telephones as heretofore constructed.

The general construction of my telephone is not broadly new; but with my improvements a practical instrument of great etliciency is produced.

2 5 A represents the circular case of one of the receiving or transmitting instruments, (it being adapted to either use,) inclosing a broad sound-chamber covered with diaphragm B, resting on the edge of the case, which is again 3o covered by cover C, to which the transmitting end of the mouth and ear piece is to be applied by the person using' the telephone; S and D, the combination mouth and earpiece. Transmitting-wire E is attached to diaphragm B by button F.

Case A is preferably made of wood, the rear part integral with tlat edges Il H, on which is laid. diaphragm Il and inclosing-case A, forming an air-chamber. Said diaphragm is tacked 4o at P to edges Il Il of case A, not screwed. Diaphragm l5 is covered (except where the opening admits sound-waves) by cover C, attached to case A at the sides by screws O O. I prefer that the face of the diaphragm be free from the pressure of the cover, and to attain that purpose I raise the cover off of diaphragm B by placing between cover C and diaphragm D small insulators R R, made of rubber, papier-mache, or other suitable o material. The attachment of cover C to case A at the side, keeping it clear Ot' the diaphragm, insures perfect clearness, distinctness, and purity of tone in words or messages passing' through the diaphragm. If cover C is attached directly to the face of the diaphragm, it will inevitably cause inequalityY and unreliability in the vibration of the dia.- phragm and a partial deadening of tone and confusion of sound. ATo Aobviate this I protect the face of the diaphragm from any press- 6o ure of cover C by insulators It It, laid in several places on the face of the diaphragm, so as to lit squarely against the rear of cover C.

The construction of the combination mouthpiece and ear-piece is another important feature of my invention. It contains no diaphragm, and is adapted to be permanently attached to or detached from cover C at the opening thereof. It is made of papier-mache or other suitable material, and consists of two 7o outwardlyflaring parts, D and S. Inner chamber, S, having an Opening large enough to fully accommodate a persons mouth, is somewhat similar to a truncated cone with a part of its side cut ont, forming two communicating chambers or passages, N M. Outer chamber, D, tlares up and curves to cover a persons ear, while the mouth is placed at the opening of chamber S to talk against diaphragm B. This combination mouth and ear 8o piece enables the sound-waves to be received with absolute accuracy, as the Waves naturally follow curved chamber D after leaving diaphragm Il, and become audible and clear by the time they reach the opening of chamberD. 8 5

In sending a message a part of the soundwaves is retiected by the inclined sides of space M, by which they are again reflected in converging' lines on the center of the diaphragm, which strengthens the sound without 9o confusing it.

Diaphragm B consists of a sheet of tin between two sheets of leatheroid. They are glued together, forming a strong and durable resonant diaphragm with greater elasticity and resonance than can be produced by any single substance.

The transmitting Or connecting wire is attached at one end to one diaphragm and at the other to the other diaphragm, the attach- 10o ment bein made in each cascby means ot' button l", made of metal about two inches in diarneter, fiat on one side and having an annular curve on the other, with tWo holes near 'the center, through which a steel, brass, or other suitable metal rod is passed and the two ends are riveted, forming a loop or hook.

The loop or hook on button F is passed through a hole punched in the center of the diaphraglnfand transmitting-wire E fastened to the loopgor hook, making a strong and durable hold on the diaphragm.

VhatI elailn as my invention, and desire to secure by Letters Patent, s-

1. A diaphragm for transmitting and receiving sound, composed of leatheroid and tin, substantially as described.

GEORGE THOMAS.

Witnesses:

S. J. GORDON, JOHN W. RIPLEY.

Images