US518263A

US518263A - Chakles milde

Info

Publication number: US518263A
Authority: US
Publication date: 1894-04-17
Anticipated expiration: 1911-04-17

Description

(No Model.)

0. MILD-E.

TELEPHONIG APPARATUS.

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Inventor:

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UNITED STATES PATENT OFFICE.

CHARLES MILDE, OF PARIS, FRANCE.

TELEPHONIC APPARATUS.

SPECIFICATION forming part of Letters Patent No. 518,263, dated April 17,1894- Application filed October 31, 1393. Serial No. 489,641- (No model.)

To all whom it may concern:

Be it known that I, CHARLES MILDE, a citizen of the Republic of France, and a resident of Paris, Department of the Seine, France, have invented certain new and useful Improvements in Telephonic Apparatus, of which the following is a specification.

My invention relates to atelephonc which, besides being very simple in its construction has the advantage that it can be used at the same time as a short and long distance tele-' phone by reason of the extreme sensitiveness of the transmitter as well as the receiver.

In the drawings, Figure 1, showsthe complete telephone consisting of the microphone and of the receiver. Fig. 2, is a sectional view of the microphone on an enlarged scale.

The same letters refer always to the same parts.

The following is the description of the microphone Fig. 2. Aisa part of the vibrating plate of the telephone to which the microphone is fixed by the means of a screw B which itself isfixed to a metallic socket C. A second screw serves for fastening there, one of the wires of the circuit tosaid socket. A Washer of cork D is placed between the bottom of the socket and the vibrating plate in order to deaden the joint. The microphone itself is fixed so that it can move in said socket C. It consists of two circular plates E of thin metal and with a corrugated surface which, when placed the one upon the other forms a flat box about five-sixths of which is filled with sieved granules of coke or carbon, chemically purified. Two sticks or beads of carbon F are arranged through the center of the platesE and are insulated from contact with the metal through the means of a paper-strip G. The two heads are in contact with said semi-conducting material in the box. In order to increase the sensitiveness of the instrument both beads are hollowed at the bottom and the hollow spaces are filled with lead, H. A small lower socket I corresponds to the upper socket C of the plate A and is provided with a small screw for the other wire of the circuit.

After having thus given a detailed description of a practical construction of my improved microphone I wish it understood that my invention is not limited to that construction alone. The lead placed in the hollow of the two carbon sticks are simply weights united to one of the carbons or to both if necessary. I can make the weights of other heavy material; I can give them the shape of rings encircling the carbons, in the shape of washers located at the bottom of the sockets C and I. I can simply make the sockets themselves heavier; in short, changes in the shape or in the material which do not affect the principle itself of the invention which is plainly'and precisely characterized by the union of suitable weights to one or to both carbon beads of my microphone.

Instead of fixing the microphone to the vibrating plate by means of a screw I can glue the same togetherwith some appropriate glue.

The insulating fittings can be of any propermaterial. The conducting wires instead of being fixed by screws can be knotted around the beads, they can be pressed between the sockets and the carbons, in short they can be fastened in any suitable way.

I claim as my invention- 1. A microphone consisting ofa metallic corrugated box partly filled with granulated and purified coke, said box having a carbon stud or head extending through it at each side and carrying a weight, one of the beads being connected to the vibrating transmission plate, substantially as described.

2. A microphone comprising the flat box made up of the corrugated plates, the vibrating, diaphragm, the opposing carbon studs extending through the corrugated plates and centrally thereof, the circuit connections and granulated filling in the box, said box extending laterally around the opposing studs, substantially as described.

In testimony that I claim the foregoing as my invention I have signed my name in presence of two witnesses.

CHARLES MILDE. Witnesses: M. CORROYER,

CLYDE SHROPSHIRE.