USRE12103E - Charles g - Google Patents

Description

No. 12,103. RBISSUED MAR. 24, 1903.

c. e. BURKE;

, TELEPHONIG' APPARATUS. APPLICATION rum) EBB. gs, 199s.

UNITED STATES CHARLES (i. BURKE, OF BROOKLYN,

PATENT OFFICE.

NE W YORK, ASSIGNOR OF ONE-11A [IF 0 h lOSlON, MASSACHUSETTS.

.ELEPHONIC APPARATUS.

:PECIFICATION forming part of Raise-lied Letters Patent No. 12,103, dated March 24, 1903.-

Original No. 719.432 dated February 3. 1903. Application for reissue filed February 28. 1903. Serial No. 145.606.

Be it known that l, Cnannns BURKE, a citizen of the United States, residing in the borough of Brooklyn, in the county of Kings and Slate of New York, haveinvented certain new and useful Improvements in Telephonic Apparatus, of which the following is a specification, reference being had to the drawings accompanyingand form inga part of the same.

The invention which forms the subject of my present application is an improved telephonic apparatus based upon the results of certain discoveries made by myself in attempts to obtain a receiving instrument for telephone-lines capable of reproducing more distinctly and audibly the words spoken into the transmitter.

Primarily the invention consists in a novel receiving apparatus; but it also includes the combination of such apparatus with a linecircuit composed of a single conductor which is not grounded at either end, I having discovered that under these conditions I am enabled to transmit with perfectdistinctncss articulate speech.

Stated briefly, and in general terms, the receiving apparatus comprises two magneto or Bell receivers arranged usually in a convenient manner, so that in use one instrument may be held to each ear. One receiver is in the line-circuit or connected with the single conductor of the same, while the other is in a local circuit maintained in inductive relation to the line by means of a plurality of induction-eoils, the long fine-wire coils of which are in the line and the short coarse-wire coils of w rich are in the local. \Vith such a re ceiv g apparatus, and particularly when the telephones and induction-coils are arranged in the specific manner hereinafter set forth, I have found that results of a novel and remarkable character may be obtained, for not only is the speech transmitted louder and more distinct than by means of any other apparatus of which I am aware, but it is also possible to transmit over an open circuit that is to say, a single conductor-which is not grounded ateither end.

I shall describe the details of my improvement by reference to the accompanyingdrawings, in which- Figure 1 is a diagram of an ordinary metallic-circuit system or line to which the re: cciving apparatus is applied, and Fig. 2 r. si milar diagram illustrating the arrangement which may be adapted for transmitting over a single ungrounded wire.

For the sake of simplifying the illustration 1 have shown my improved receiving apparatus as applied to one end of the circuit only; but it will be understood that it maybe used at both ends in lieu of the ordinary receiver.

Referring to Fig. 1, A designates an ordinary two-wire or metallic telephone-line circuit. At each end of this circuit there is the usual long fine-wire secondary coils B B of an induction-coil for transforming currents of low potential in the local circuits to currents of high potential in theline. The shortwire primaries C C of the induction-coils are included in the local circuits D D, respecfor producing pulsating currents in the local circuits to correspond with the sound-waves affecting the transmitters. The line-circuit includes in addition to the usual fine wire coils B B a plurality of coils G, which form a part of the receiving apparatus. These coils are of long fine wire, similar to the secondariesB B, and may vary in number. ly way of illustration I have shown eight; buta less or a greater number may be employed, and generally I have found thatthe larger the number the better-the results seen red. I haveused, for example, in experimental tests twenty or more of such coils with apparently improved results with every additional coil. These coils constitute the primaries of induction-coils, each having'its appropriate secondaryl'l of shorter and coarser wire, all of such secondaries being connected with a local circuit K, includin a magneto-telephone receiver L. These coils retransform the high-potential currents of the mainline to low potential and high-amperage currents in the local circuit. 'Thehigh-amperage currentsthus produced greatly increase the eificiency of the magnet on the diaphragm of the telephone-receiver. The secondaries 11 may be all in series with each other, althoughitis not necessary to tively, in which latterare also the batteries, E E and carbon or other transmitters FD adhere to this arrangement, while the same l$d0ll0 and, as shown, by the receiver M at the left. Whenthesystem is thus arranged and the transmitter F operated by the voice, a differeuce in the loudness and clearness of reproductionof the speech by the two instruao ments L and M will be detected by holding first one and then the other to the ear; but if both instruments be held one to each car a remarkably-pronounccd effect will be at once apparent, for not only is the speech much louder than when a single instrument is used or when two instruments, both in the line-circuit, are held to the cars at the same time, but the articulation is much more distinct. I do not advance any theory in ex- .planation of this fact, deeming it sufiicient for purposes of this case to state that whenever the instruments L M of ordinary con:

struction are used in substantially the mannerabov'e described they will give results of the nature indicated.

A feature of great utility in my improved receiving instrument resides in the fact which I have discovered that it is capable of operation and use-even should one of the wires of 40 the line be cut and the circuit interrupted. It'results from this that the receiver may be a primarily applied toand used for operating a system havingbut a single ungronnded line-wire, as illustrated in Fig. 2,'in which a receiving instrument is shown at each end of the line, the latter being a single ungrounded.

conductor. In such a caseasthis the speech is transmitted, but not so audibly or distinctly as when a. metallic circuit is used,

I but sufliclently well for ordinary purposes,

i and the reason for this appears to he that with an "interrupted circuit such as illustrated the telephones M M, connected directly with tue line conductor, emit practically no articulate sounds, although those in thelocal or secondary circuits reproduce the speech very clearly and distinctly. 7

It will be understood that in practice the usual arrangement of call-hells and switches will not need to be disturbed in any material respect whenapplying my improvements "to a circuit and that all of the instruments H 'and appliances used in carrying out the in- "vention may be of the ordinary and .well- S ELBY lug nowdescribed my invention and the manner in which the same is or may be carried out, what I claim is 1. In a telephone system the combination with a line, of a local circuit, a plurality of independent induction-coils composed of'long fine-wire and short coarse-wire coils, the firstnamed coils being connected with the linecircuit and the others being connected up in the local circuit, and a telephone-receiver in the local circuit, as set forth.

2. In a telephone system the combination with a line, of a local circuit, a plurality of independentinduction-coils,comprised ot'pri: maries and secondaries having a difierent number of turns in the differentcoils, thelong fine-wire primaries being connected with the line-circuitandthesecondariesbeingincluded in the local circuit, and a telephone-receiver in the local circuit, as set forth.

3. In a telephone system the combination with a line, composed of a single ungrounded conductor, not forming a com plote circuit, of a plurality of independent inductioncoils, composed of long fine-wire and shortcoarsewire coils, the fine-wire coils being connected up in the line, a closed or complete local circuit at the end of the line, including the coarse-wire coils of the induction-coils, and a telephone-receiver, connected with the local circuit, as set forth.

4. In a telephone system the combination with the line, of alocal circuit, a plurality of independent ind notion-coils composed of long fine-wire and short coarse-wire coils, the first- .named coils being connected with the line,

and the others with the local circuit and two magneto-telephones one connected with the local circuit and the other with the line and constituting parts of a single receiving instrument, as set forth. 7

5. In a telephone system havinga single nngrounded main line, means for modifying an electric current to correspond with soundwaves, means located at one end of the main phone-receiver in circuit with said last-mentioned means. I a

6. I'n'atelephonesystemasingle ungrounded main line, a telephone transmitter-circuit at one end and areceiver-circuit at the other end of the said main line, induction-coils connected to said mainline for transforming pulsating currents caused to (low in the transmitter-circuits to corresponding currents of high potential in said main line and retransfor'tning said currents to corresponding currents of low potential in the receiver-circuit.

CHARLES G. BURKE.

Witnesses:

M. LAWSON DYER, R. STEPHEN Donovan.

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