US443526A - johnson - Google Patents

Description

(No Model.) E. H. JOHNSON.

TELEPHONE. No. 443,526. Patented Dec. 30, 1890.

1 U WW I UNITE STAT-Es PATENT Fries,

EDIVARD ll. JOHNSON, OF NEW YORK, Y.

TELEPHONE.

QPECIFICATION forming part of Letters Patent No. 443,526, dated December 30, 1890.

Application filed April 24, 1884. Serial No. 129,065. (No model.)

T0 at wit/0121, it may concern.-

Be it known that I, EDWARD H. JOHNSON,

of New York city, in the county and State of New York, have invented a certain new and useful Improvement in Telephone-Transmitters, of which the following is a specification.

The object I have in view is to produce a telephone-transmitter for transmitting articu late speech, capable of use directly in the line, which may be kept constantly charged by a battery located at either end of the line or at the exchange or central office, and proportioned to the length of the line. In this way a telephone-exchange system could be produced wherein nobatteries would be required at the subscribers telephones and no induction-coils would be necessary, the transmitters acting directly upon a line-current of constant direction to vary it by throwing it into pulsations practically in unison with the soundwaves. The receivers would also be directly in the line, and since the line would be constantly charged simple electromagnetic receivers could be employed, the diaphragms being kept under tension by the constant current, and no permanent magnets being required for that purpose. The instrument is designed to produce great variations in the line-current, similar to those produced by a telegraph-key, and hence by properly proportioning the transmitter and receiver to the resistance of the line the same length of line may be used as in telegraph systems, and the telephone system will be reduced to the simplicity of arrangement employed in the present Morse telegraph. The deleterious effects of induction from adjoining lines will also be overcome.

While my transmitter has advantages of being adapted for the use explained, it is also capable of use with induction-coils, like the carbon transmitter, when proportioned or connected properly for such purpose.

The invention covered by the present application for patent is limited to the telephone-transmitter per se, however it may be used.

In carrying out my invention I make use of a number of independent and free circuitcontrollers acted upon independently by the sound-waves and free to move in unison with the condensations and rarefactions of the atmosphere produced by the vocal organs. These circuit-controllers serve to vary the number of definite units of current in the telephone-circuit by changing the number of definite units of resistance or counter electromotive force in circuit, or both.

For my instrument I employ for each circuit-controller the arrangement shown and described in my patent, No. 381,382, dated April 17, 1888, or any modification thereof covered by such application, and mount a number of these circuit-controllers in one i11- strument, with the heads of the piston soundwave receivers in a common sound-wave-receiving chamber. The magnet or solenoid coils are connected in any desired arrangement of series, multiple series, or multiple arc in one circuit, which may be the line-circuit or the primary of an induction-coil. I arrange all the independent circuit-controllers so that they are all situated at different distances from the central point. I prefer an arrangement in the form of a geometrical spiral. I find that this arrangement of the circuit-controllers, so that they are all at different distances from the central point, gives the best results in the transmission of speech, and I believe this to be due to the fact that there is a progressive action of the different circuit controllers.

In the accompanying drawings, forming a part hereof, Figure 1 is a front view of the instrument, the door of the inclosing-box being thrown open; Fig. 2, a side elevation of the instrument with the inclosing-box in section; Fig. 3, a view from the rear of the instrument; Fig. 4C, a sectional view, on an enlarged scale, of one piston sound-wave receiver and the parts connected therewith; Fig. 5,a vertical section of four of the piston sound-wave receivers arranged in two series, and Fig. 6 a representation of the current-pulsations caused by the instrument when used directly in line.

In the block A, of hard rubber or other suitable insulation, are mounted a number of the independent circuitcontrollers having the arrangement of a geometrical spiral, as shown in Figs. 1 and 2. Each is composed of an electro-inagnet B, a piston sound-wave receiver G, carrying armature a, and guided and retarded in its movement, and points I) c,

of platinum or other suitable metal, carried by the magnet and armature, as shown,these parts being more particularly described in my patent, No. 381,382, dated April 17, 1888.

Each magnet B is carried by the hollow end of aplug D, of hard rubber or other suitable insulator, having an enlarged head which fits tightly one of the openings through the block A and is forced therein. The body of the plug does not quite fill the opening in block A, and in the annularspace thus formed the piston C works freely,being guided both internally and externally by the plug D and the block A. The heads of all the pistons are flush with the face of block A. This block is inclosed in a suitable case E, having door F and mouth-piece G, and this case forms a common sound-receiving chamber for all the pistons. The wire of each magnet is soldered at one end to the magnet-core, and the other end is carried out through the plug D to the back of block A. A connection 2 is made with the core of each magnet, and is carried out through plug D to the back of block A. A pin (Z extends through the block A adjacentto each circuit-controller, and on the front of the block is connected by a wire 3 with the armature a and electrode 0, while on the back of the block it is connected with n1agnet-wire 1. It will thus be seen that in each circuitcontroller the coils of the magnet and the electrodes 11 e bear a shunt relation to each other, the contact of the electrodes short-circuiting the 1nagnet-coils and the separation of the electrodes throwing such coils into circuit. All the oircuit-controllers are connected in one circuit l 5. This connection may be any desired arrangement of series or are.

In Fig. 5 by utilizing the end connections 6 7 only the circuit controllers would be placed in one series, while by the use of connection 8 two series can be formed. Six binding-posts c (3 c c c e are shown, to which run connections 9 10 ll 12 13 14, dividin g the circuit-controllersinto five series. By their use a simple series or a number of arrangements in multiple series can be made. I prefer for an instrument to be used directly in the line to employ a simple series arrangement; but with an induction-coil a multiple series or multiple-arc arrangement would be preferable, although the particular arrangement in either case would depend upon the resistance of the line and the resistance and power of the magnets.

The magnetrcoils form the definite units of resistance, which are thrown into and out of circuit by the circuit-controllers. This re sistance, however, is multiplied by the countereleetro-motive force of the magnet when the short circuit is broken, and a much greater reduction of the current is produced than would be due to the introduction of the resistance of the wire alone, and the pulsations are sharpened by the partial or complete neutralization of the static charge.

I propose using a much larger number of circuit controllers in my instrument than shown in the drawings, although a lesser number could be employed, and for long lines these are preferably arranged in series.

By the operation of the line-transmitter the current is thrown into pulsations which are in unison with the articulate sound-waves.

The pulsatory current is illustrated diagrammatically in Fig. 6. The line 6 represents no current. The line f represents the current when all the resistance is in circuit. The line g represents the current when the resistance is all cut out of circuit. The telephone-circuit being constantly charged by a current of one direction, at no time will there be less current flowing than represented by line f. The pulsations caused by the transmitter are represented by the zigzag line 71, varying between the lines fg, since the pulsations will vary between points of maximum and minimum current.

\Vhat I claim is- 1. In a telephone-transmitter, the combination, with one circuit, of two or more sets of electrodes and definite units of resistance located in shunt-circuits around such electrodes, substantially as set forth.

2. In a telephone-transmitter, the combination of two or more sets of electrodes, two or more piston sound-wave receivers, and electrically-operated devices for automatically adjusting the electrodes and forming definite units of resistance which are throwninto and out of circuit by the movement of the electrodes, substantially as set forth.

In a telephone-transmitter, the combination of a number of sets'of electrodes and independen t controlling devices arranged at different distances from a central point, substantially as set forth.

at. In a telephone-transmitter, the combination of a number of sets of electrodes and independenteontrolling devices spirally arranged, substantially as set forth.

This specification signed and witnessed this 9th day of April, 188i.

EDIVARD ll. JOHNSON.

Witnesses:

War. II. I\.IEADOWCR()F'1, A. W. 'KIDDLE.

ICC

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