US2285585A

US2285585A - Transmitter, receiver, and amplification system

Info

Publication number: US2285585A
Application number: US308783A
Authority: US
Inventors: Karl Heinrich
Original assignee: Individual
Current assignee: Individual
Priority date: 1939-12-12
Filing date: 1939-12-12
Publication date: 1942-06-09
Anticipated expiration: 1959-06-09

Description

June 9, 1942. H, KARL l'2,285585 TRANSMITTER, RECEIVER, AND AMPLIFICATION SYSTEM 3 Sheets-Sheet 1 Filed Dec. l2, 1939 June 9, 194.2. H, KARL 2,285,585

TRANSMITTER, RECEIVER, AND AMPLIFICATION'SYSTEM Filed DSC. 12, 1939 3 Sheets-Sheet 2 H. KARL June 1:),4 1942.

TRANSMITTER, RECEIVER, AND AMPLIFICTION- SYSTEM Filed Dec. l2, 1939 3 Sheets-'Sheet 3 Patented June 9, 1942 l l UNITED STATES PATENT CFFICE TRANSMITTER, RECEIVER, AND AMILIFICA- TION SYSTEM 12 Claims.

Part of this invention is also incorporated in the United States Patent No. 2,193,874 that was granted to me under date of March 19, 1940, and the application (Serial No. 116,462) of which was led December 18, 1936, and said part representing a diaphragm that is an invention distinct from the remainder of said patent application Serial No. 116,462, division was therefore required.

Said diaphragm, being generally made of a core of certain material and a coating thereon that together produce a clearer and more voluminous voice than all steel membranes, is therefore more adapted to suit the public than the latter. Besides the diaphragm there are other co-operating means as for instance a novel way of transforming the sound vibrations into electrical impulses that are thus sent to any remote place that is in electrical connection with said transmitter and thus being adapted to receive said impulses and having them transformed into sound vibrations by the receiver disclosed in the present invention. This invention comprises therefore a transmitter of novel construction and also a receiver of novel construction and both comprising the improved diaphragm mentioned above.

'I he invention comprises also such handy construction of the transmitter and of the receiver, that both can be detached separately from the standard thereof and simply used as ear and mouth pieces, respectively, whereby only a relatively long cord bearing insulated conductors, keeps the ear and mouth pieces in electrical connection with the remainder of the telephone and thus permits the person using the telephone to hold only the relatively light ear piece in one hand and also, only if desired, the mouth piece, in the other hand.

The invention comprises also means for securing the ear and mouth piece to the standard in connection with which they can be used also.

The invention comprises also a new means for making or interrupting electrical connections with the connecting station and the user on the other end without the necessity of hooking or unhooking the receiver or of placing or taking it oli, respectively, from the socket or other part of the telephone.

Furthermore, the invention comprises novel means for placing the ear and mouth piece on a dish-like part for the easy handling at any time of these parts whereby said dish-like part is so constructed that electrical connections will be interrupted when the receiver willbe lifted from it.

45 larged .the receiver The invention comprises further, new systems of amplifying the electric impulses set up in the connections of the telephone and transforming these impulses into sound vibrations.

rIhe invention comprises diaphragms of the re- 15 ceivers, the latter of which are adapted to amplify the sound which is transformed from said electrical impulses which are then amplified.

The invention comprises also a system of amplification in which the voice will be amplied when request therefor is made and such amplication may be had only for one of the two parties or for both.

The invention comprises also systems in which telephone amplification will be had, whereby one system will be adaptable for near connections and another for longer distances.

The invention comprises also suitable connecting places, other than telephone booths for making connection with the connecting station by means of the detached (personal) ear and mouth piece, and thus becoming connected by telephone with the demanded party.

The invention comprises also suitable boxes or covers for the contacts at said connecting places that are or are not confined in telephone booths.

Other novel features will appear in the course of the specification.

The invention is illustrated by the accompanying drawings of which:

40 Figure 1 shows the diaphragm of the receiver in front view;

Figure 2 shows the diaphragm of the `receiver in sectional side View;

Figure 3 shows in a sectional view, and enhaving the diaphragm of Figures 1 and 2;

Figure 4 is a diagrammatic representation of the connection station (or the central station); Figure 5 is one of the modes of keeping the ear and mouth pieec, that is, the receiver and the transmitter, handy on a dish-like part;

Figure 6 is a sectional representation of the receiver having a cone shaped diaphragm;

Figure 7 shows the diaphragm of the transmitter. in front view;

showing also diagrammatically electrical connecl tions and a standard to which the transmitter can be affixed and detached at will; showing also a circuit connector for establishing electric circuit connection with the connecting station;

Figure 11 shows in sectional elevation another l5 type of transmitter whose primary and secondary windings of the transformer are separated from the hull of the transmitter proper although being in electrical connection therewith and the transmitter being of a type that bears a container of 20 gaseous or of liquid or of a semi-liquid matter for transforming the sound vibrations into electrical impulses and having also a circuit connector for the electrical circuit connection with the connecting station, whereby this connector is 7.25

different from the one shown in Figure Figure 12 shows another purely mechanical intermediary means for transforming the sound Vibrations of the diaphragm into electrical impulses;

Figure 13 shows in section the mechanism of the connector shown also in Figure 11;

Figure 14 shows the special contact cover and coin box;

Figure 15 shows the telephone connections with `35 ampliers;

Figure 16 shows simplified telehpone connections with amplifiers` Referring to the diaphragm of Figures 1 and 2 there is a frame I on which is stretched a sheetj- "4() of paper 2, of suitable quality and thickness or a piece of slik or of rayon or one of other cloth may serve. A very thin piece of wood, of such character, that like r, is very adapted to create* sound vibrations, is also adaptable. or cloth of silk or rayon or said thin piece of wood is to be properly lacquered or varnished and especially with the kind of lacquer that dries very hard, such as the lacquer used for lacquer-f If cloth is taken, such as, silk or ing Violins. rayon or others, it might be necessary to make the diaphragm of cone shape in order to stretch the cloth sufficiently. An example of a cone shaped diaphragm of a receiver is shown in` Figure 6 which will be described subsequently. 5

If paper is to be used for making the diaphragm it should be made wet with water and mounted on the frame I in moist condition. It will then be properly stretched and allo-wed to dry thor-` oughly. In the completely dried condition th paper is then suiiiciently stretched and can be lacquered. This procedure applies also to the diaphragm shown in Figures '1 and 8.

Referring again to the diaphragm 2 of FiguresI 1 and 2 there must be iron filings 3 strewn on the 65 still wet lacquer and especially at the part of the paper that will be nearest to the poles of the electromagnet that is then included in the receiver, as can be seen from Figure 3. The iron filings 3 are then only situated around the center To of the diaphragm and only on the side that faces the poles of the electromagnet when it deals with a receiver, which is contrary to a known example of a receiver diaphragm which is entirely made of hard rubber or shellac or Celluloid or Choroshows in sectional elevation the 5 This paper 5 lithion or other materials in which iron in foraininated or comminuted form may be embedded, which is then contained in all parts of the whole diaphragm. By embedding the iron filings only in the lacquer that coats the side of the core of the paper etc. and especially only the area that faces the poles of the electromagnet, vibration of the diaphragm will be obtained at the slightest electromagnetic impulse in the electromagnet, as will be explained further subsequently, and the vibrations will be the more pronounced when the far greater part of the diaphragm is left free from iron particles that tend to make it heavy. In the latter gure is also shown that the electro-magnet comprises two cores or Shanks 4, 5 which are partly enveloped by the windings 6, 1, respectively The shanks 4, 5 are connected to the Shanks 8, 9 of the permanent magnet l. The end II, I2 of the shanks 4, 5, near the diaphragm, should be about l, 11/2 or 2 of a thousandth of an inch distanced from the diaphragm 2. Connected to the winding 6 is the wire I3 and connected to the winding 1 is the wire I4, and all are in the same circuit. The latter may be grounded at I5, while the wire I3, forming also part of the circuit, is extended to the connecting station, shown in Figure 4, where it forms a contact I5, in which can be inserted the contact I1. This will take place when the operator received a call to connect with the contact I6 which might have a special other number. The operator at the connecting station thus connects the circuit, which when closed, rings the bell I8.

The parts of the receiver that must be kept together, as, the frame I, the diaphragm 2, the electro-magnet 4, 5, the permanent magnet I and the windings 6, 1 are held together by the frame I9 of insulating material which has the special ear piece 20. The conductors I3, I4 are continued in a cord 2|, of known make, and are surrounded by insulating material 22.

For protecting the diaphragm 2 a wire screen 23 is placed a little in front of the diaphragm and held in the walls of the ear piece 20. A ring 24 may conceal the end of the narrow hose of the cord 2 I.

The receiver of Figure 3 may be placed on a dish-like part 25 (see Figure 5) which has its bottom formed as two

contacts

26 and 21, of which the one indicated by 26 will be separated from the contact 21 when the receiver will be lifted, as when the person, hearing the sounding of the bell I8, is to listen to the message coming over the telephone and thus places the receiver to the ear. The electric circuit causing the ringing of the bell I8 will be interrupted thereby and the ringing of that bell thus stops. rihe fiat contact 25 will be lifted and thus disconnected from the flat contact 21 by the spring 28.

' For announcing that somebody is listening and for making the conversation with the party at the other end of the wire the person that lifted up the receiver first, must then use also the transmitter or mouth piece 29 which may be Vplaced at some other part of the dish-like part 25, as

shown in Figure 5. The details of the transmitter will be described subsequently.

Referring to the cone shaped diaphragm 30, shown in Figure 6, it consists preferably of cloth such as silk or rayon although cotton may be .used also, The piece of cloth will be stretched on the frame 3|, whereby the center point wil be held forward by a forward protruding part 3i diaphragm 36, being also the diaphragm of aA receiver, must also have the iron lings embedded in the lacquer that covers the surfaces of the cloth or other suitable material.

The cores 34, 35 of the electro-magnet 36 thus must have the ends so inclined, est t the diaphragm, that they Will have the same direction as the cone shaped wall of the diaphragm, in order to be very close to the inner surface of it, but without touching it. 31 indicates the permanent magnet and 38 the part of the frame or hull that will be held against the ear. There might be a cone shaped protection screen 39 employed. The other parts of the receiver of Figure 6 are otherwise like those shown also in Figures 3, 4 and 5.

From the description of the receivers it is shown, that the electric impulses set up in the windings 6, 1 of Figure 3 or the windings 46, lll of Figure 6, energize the cores 4, 5, 34, 35, respectively. These cores, being thus made magnetic in the degree which is commensurate with the degree of the electric impulses, attract alsc` the iron filings that are embedded in the lacquer of the diaphragms, and since these iron lings cannot separate themselves from the lacquer and consequently from the diaphragms, the latter must therefore make the movements or vibrations which are caused by the alternate attraction and then release of the iron filings that are embedded in the then hardened lacquer. The stiffened diaphragms, being thus forced to vibrate, produce thereby sound waves that conform with the electric impulses set up in the windings and cores of the receiver.

In order to synchronize the Vibrations of the diaphragm of the receiver with those of the transmitter it is therefore advantageous to make the diaphragm of the transmitter of the same material that is taken for making the receiver, whereby no iron filings will be embedded in the lacquer. Using for the transmitter the same material of which consist the receiver, is however, not an absolute necessity, since the transmitter diaphragm might consist of one of said other materials mentioned before and even the al1-steel membrane might be retained under certain circumstances.

The reason why the materials mentioned, that are non-metallic, are preferable over all metallic diaphragms is, because these materials discounting the frame l, 3|, respectively, and in cooperation with the hardened lacquer being lighter and more sensitive than metallic diaphragms, are adapted to make more pronounced vibrations than the steel membranes and consequently will react upon the slightest impulse, either the sound or the electric impulse. Since then the strong and medium impulses are also proportionally increased there is a greater perceptibility of the sound created by the receiver than it is the case with the all steel diaphragm. This permits again that other parts in the receiver, as well as in the transmitter can be made smaller in size than with the transmitters and receivers, the diaphragms of which are in the form of steel membranes, without impairing thereby the vibrations of the diaphragms.

Referring to the transmitters of which two complete examples are shown, namely, one in Figure 10, which will be described rst, and-one which are nearin Figure 11, one of the purposes of the invention is to make the mouth piece 42 detachable from the standard 43.y This permits to hold the relatively small mouthpiece (the transmitter) in one hand and the relatively small receiver (the ear piece) in the other. Many persons like to walk back and forth while talking and do not like to have relatively voluminous or heavy instruments in their hands. The telephoning, while being in bed or in any other situation, is thus made easy and consequently more agreeable. A business man may carry the mouth piece and the ear piece in his pockets while being in the oflice or in any other place, and may detach them from the contacts 45 that have guide channels'46, 41 into which can be inserted the contact extensions 48, 49 (the insert) that form part of an attachment 56 to which are properly connected the wires 5|, 52 in the cord 53. The Wires 5|, 52 are insulated froml each other, as are also the metallic walls of the guide channel 46 from those of the guide channel 41. The contact extensions 48, 49 are also insulated from each other and the former is electrically connected with the wire 5| while the other is connected to the wire 52. To the metallic wall of the guide channel 46 is electrically connected the wire 54 while to the metalic walls of the guide channel 41 is electrically connected the Wire 55, which is grounded at 56. Wire 54 is extended to the connecting station that might be the central station. Wire 54 must be in connection with the contact I1.

Another pair of guide channels 51, 56 are provided for to permit the insertion of the Contact extensions 59, 66 (the insert) of the receiver (see also Figure 3). The metallic walls of the guide channel 51 are in electrical connection with the wire 54, while the metallic walls of the guide channel 58 are in electrical connection with the wire 55.

If the telephone company would provide guide channels as explained in connection with Figure 10, with every telephone booth and also at many other convenient places, it would facilitate those persons that carry with them their personal receiver and transmitter, to converse by telephone from any of the numerous places by using their own set of transmitter and receiver (the mouth and ear piece). A regular telephone booth might be only miles away.

This innovation is not only made to suit fastidious people that do not like to handle receiversand transmitters that have been handled by numerous other enormously simplify the system and reduce enormously the cost of installation of the so simplied apparatus. It would then suit greatly the user of the telephone that may carry his own mouth and ear piece, and would suit greatly the company for the economic and simple way of installation. Y

Referring more particularly to the scheme shown in Figure 11 the mouth piece (the transmitter)l will be detached from the primary and secondary winding 6|, 62, respectively, of the transformer 63. The transmitter, thus being reduced in weight, can be made so light and small that it can be carried in the vest pocket. It will then be necessary to install the transformer 63 in some secure place and connectit by the

wires

64, 65 to the metallic walls of the guide channels 61. The battery 68 must then be 'ineluded-in this part circuit as well -asA the primary Winding 6|. It will be comformable to indicate people, but the scheme wouldl by sign or other information, if the guide channels their walls, respectively, are in electrical connection with a transformer. There might be therefore two kinds installed of which one is and the other is not in connection with a transformer.

'Ihe circumstance that the diaphragm can be relatively small permits therefore also to make the transmitter comparatively small. The transmitter of Figure may be used at such numerous places by workmen of the telephone company or other agents, in which no transformers are to be installed, while the transmitter of Figure 11 will be used only by private persons, at such places, where the transformers are also in electric connection with the walls of the guide channels.

Other arrangements in the use are obviously possible and also mechanically there are deviations possible, as for instance, the guide channels for the inserts may be arranged at the ends of the wires that are permanently associated with the transmitter (the mouth piece) while then the wires being permanently in electrical connection with the primary winding of the transformer must then be connected to the insert.

In connection with the receiver the insert may also replace the part with the guide channels while the latter will then be part of the detachable portion of the receiver.

In order that the telephone company may be duly recompensed for the use of the telephone connections and the service of connecting, there are in general two ways for receiving its dues. One of these ways consists by including a general fee for a large number of calls when a person acquires a set consisting of a receiver and a transmitter for personal use only. In this case the person that acquires the receiver and transmitter will also be handed a key 68 by means of which the cover 69 can be unlocked and turned in such position that it permits the insertion of the insert. A similar cover should also be in connection with the transmitter guide channels. The cover 69, however, should be big enough to cover all four guide channels, namely, those indicated by 46, 41 and 51, 58.

Since the scheme in connection with the transmitter of Figure 11 is similar to that shown in Figure l0 the same applies also to the guide channels that will be used for connecting the transmitter of Figure 11 and a cover will serve for protecting the otherwise exposed contacts, whereby the person, having the key, can thus open the cover and insert the inserts of his mouth piece (the transmitter) and ear piece (the receiver) The other mode of getting its dues is, that the telephone company provides a nickel drop near every lock of the cover B9 and to construct the lock so, that part of it prepares the lock bolt for being pushed to open position which is then effected by the key which the caller carries with him and which should be suitably attached to the transmitter or to the receiver.

A convenient structure of such lock is illustrated in Figure 14. The cover 69 is shown partly broken away to show the other mechanisms that co-operate with the lock. The lock bolt 1|) is thus shown in locking position, whereby a spring sustained relatively thin bar 1| will be moved between the wall 12 and the end wall 13 of the bolt 10. The latter thus cannot move backward, even if the key is inserted and it is tried to turn it. Only after the insertion of a coin, say a nickel, the thin bar 1|, that might iii) be pivoted, will be pushed down and out of the way of the lock bolt 10. The additional weight of the nickel forces the relatively weak spring 15 down, bringing thus also the thin bar' 1| down and in engagement with two spring contacts 16, 11 that usually are separated from each other. These contacts 16, 11 form part of an electric circuit by means of which, and in co-operation with a sounding or visually perceptible means, will be announced that a nickel has been dropped in that certain box. The operator in the connecting station may thus make a note etc. and then disconnect temporarily the bell or what ever means are employed for announcing the insertion of the nickel and will then listen to the caller and make connection with the demanded number. At this instant the caller might ask for amplification if he should be hard of hearing or if he simply likes it better, or if several persons are eager to listen at the same time. The details in connection with the amplification will be pointed out subsequently.

The spring contacts 16, 11 are so formed that they hold the thin bar 1| and thus allow the nickel 18 to drop through another slit to fall into a special box, especially provided for the coins. This special box is shown underneath and since similar boxes are well known, is not further described; the same will be also provided with adequate locking means as known. The lock bolt 10 is always urged by the spring 1S to the forward position in which it locks the cover 69 when the latter is pressed against the casing Bil. While thus locking the cover 69, a part 8| in the box will separate the two spring contacts and the thin bar 1 I, being urged upward will then be situated between the wall 12 and the rear edge 13 of the lock bolt 10 and will thus prevent the latter to be moved by a key, or moved otherwise, to open position unless the required coin is inserted. It will be noted, that through the forward urging of the lock bolt 16, by the spring 19, no pressure will be exerted upon the thin bar 1| excepting a temporary pressure when somebody tries to move the lock bolt 1E) to open position with a key without, however, inserting the coin. The thin bar having no obstruction, other than that of the spring 15, readily moves down, following the weight of the nickel.

Referring to the other details of the transmitters the diaphragm, which might also be coneshaped, as shown in Figure 9, does not need to have iron filings embedded in the lacquer that covers the cloth, or paper, or thin wood piece, but for creating a diaphragm that has the same weight and consequently the same vibrating quality as has the diaphragm 2 or 3:1 of the receiver, there may be iron filings strewn in the still wet lacquer that covers the cloth, paper .or wood, or other suitable fibrous material, of the diaphragm. The synchronization will thus be had that renders the electric impulses into sound waves that correspond with those caused by the person that speaks into the transmitter.

The transmitter of Figure 9 that has a cone shaped diaphragm 82 is similarly constructed as the diaphragm of Figure 6. In addition, however, there are lacquered fibres or bristles or horse hair, that is lacquered, or other delicate means B3 of certain stiifness and flexibility, that are secured to the part of `the diaphragm that vibrates the most vigorously, which is the part between the apex 33 and the frame 3|, and which means are adapted to translate the vibrations of the diaphragm 82 upon the metallic membrane 84, which does not need to be of steel, but of any other suitable metal, as for instance silver, copper or brass. The ends of these fibres etc. 83, that touch the metallic membrane, should advantageously be provided with an insulating material, so as to prevent electric energy to deteriorate or burn the fibres etc. and also the diaphragm, because the metallic membrane forms a connection of an electric circuit. Behind the metallic membrane 84 there is metal Wool 85 placed which should touch the metallic membrane and also the conducting plate or part 86. Instead of the metal wool there might be granules of carbon or graphite or charcoal employed although the metal wool, preferably of a good conductor, is preferable on account of its better conductivity and flexibility. To the metallic membrane 84 is connected the wire 87 which leads to one of the ends of the primary winding of the transformer, which is not shown, but since the mouth piece shown in Figure 9 is supposed to be of the character of thecmouth piece shown in Figure 11, which is detachable from the part that embraces the transformer, reference is therefore had to that particular arrangement, shown in Figure 11, which has been described previously. Referring again to Figure 9 the wire 88 that is connected to the plate 88 leads to the battery which in Figure 11 is indicated by 89. The wire indicated by 84 in Figure 11 leads then to the other end of the primary winding ,to which it is connected.

Referring to the Figure 10 the diaphragm 99, shown also in Figures 7 and 8, is flatly mounted on the frame 9|, and the latter is insertable in the hull 42. The diaphragm 90 may have also the iron filings 3 as it is with the diaphragm of the receiver, but only for synchronizing purposes, as has been explained previously.

At the interior side of the diaphragm 99, and centrally located, there is a part 92 secured that must be very light and which could consist of the marrow of some plants or of cork and the free end should be covered with insulating material. A Very ne leaf spring 93 is secured with its one end at 94, Where it is insulated from other parts, but a conductor 95 is electrically connected thereto. The free end partrslightly touches the insulating material on the part 92 and the free end part of another fine leaf spring 96 touches also slightly the leaf spring 93. Leaf spring 98 is'secured with its other end to the plate or wall 9'! which is in electrical connection with the primary winding 98. The latter has also at its other end a conductor 99 which leads to the right side of the battery |99. To the left side of that battery is connected the wire 95. To the secondary winding |9| is connected the wire 52, while the wire 5| is not directly connected to the other end of that winding. There is a push button |02 of any convenient character with which an electrical connection and disconnection between said other end of the secondary winding |9| and the wire 5| can be made. This switching device |02 might chiefly serve when the insert of the transmitter is inserted in the guide channels at home, but no conversation is intended. The push button thus will remain in circuit disconnecting po-I sition. Even with connecting contacts 45 (guide channels) at other places than the home, the push button will be handy for interrupting communication until the right moment is at hand. In order to restore the push button |02 to noncontacting position, in which it interrupts the electrical connection between the wire 5| andthe secondary winding ,|0|, after it had been pushed in to contacting position, there is another push button |03 arranged at the opposite side of the hull and a partly curved rod |94 is secured to it and also to the push button |82. If then the push button |02 will be pushed in, the push button |03 will then be pushed out, and the push button |02 is then in contacting position. By pushing then the push button |03 in again the push button |02 will thus be pushed out by the rod |04 and will make said disconnection between the wire 5| and the secondary winding |0| Looking now at Figure 4 it will be seen that the bulby |95 will light up when the circuit will be closed that comprises the battery |00, because the wire 54 also shown in Figure 10 is in electrical connection with the secondary winding |0| whose other end is grounded at 58. The operator at the connecting station may then connect after any known kind of announcement including the voice of the caller, the contact (switch plug) I1 with the contact I6 and thus establish an electric connection with the bell I8 and with the receiver of Figure 3 or Figure 5 or both.

In Figure 11 the main purpose of the construction consists in reducing still more the weight of the transmitter, so that the latter may be carried easily in the pocket of any person .or in the hand bag of a lady, including also the receiver of Figure 3 which is also the one shown in Figure 5, or it may be the receiver shown in Figure 6.

The transmitter of Figure 1l vdistinguishes itself greatly from the transmitter of Figure 10. The diaphragm |01 is similar to the diaphragm and is also similarly mounted on the frame |08. At the center of the interior side of the diaphragm |01 there is a light part |09 secured, in which is inserted bristle H0. The right side end of the wire or bristle ||0 abuts against a steel membrane or one o-f any other suitable metal, such as silver, copper etc. This membrane closes up a vessel ||2 of glass or porcelain ,or of any other suitable insulating material that should have an opening |3, that can be tightly closed by a stopper or the like means lill.

conductor ||5 that is secured to a plate H8, which may be of copper .or of any other suitable metal.y The conductor H5 is extended into the cord ||1 and is insulated therefrom. Likewise is also a conductor H8 extended into the cord ||1 and insulated from both the latter and the conductor H5. Conductor I8 is secured to the metal membrane at a part that is nearest to the outer edge thereof, and the other end of that conductor forms the insert extension ||9 that is insulated from the insert extension |20. The latter is the end formation of the conductor ||5.

Into the vessel ||2 will be introduced the gas or vapor that is known to be a good electricity conductor and which is also adapted to correctly transform the vibrations of the membrane into electrical impulses when an electric-current is passed through it. It is therefore important that said gas or vapor has the correct density and that only then the closing means` I4 should close up the vessel I |2.

Any gas that does not explode or expand too heavily will be suitable, and in such category may be ranged lighting gas although others may be even better. Among the vapors, that could a very fine but stiff wire or Atthe center of thev right side wall of the vessel 2 penetrates a.

6 be used, must be ranged first the fumes of mercury.

Instead of fumes or gas there might be liquids o-r semi-liquids filled in the vessel H2, which again might contain suitable ingredients. One of these semi-liquid means might consist of paste in soft condition or any suitable kind of jelly having carbon or charcoal dust or powdered graphite, iron, silver or copper or brass mixed therein in certain proportion.

Ifl the insert extensions IIS, |20 are inserted into the guide channels of the stationary connecting part 51` the electric circuit will be closed that comprises the following conductors: the battery 68, the wire 64, the primary winding 6I of the transformer 63 the wire E5, the walls of the guide channel in which is inserted the insert |20, the wire II5, the plate I I6, the gas or fumes or liquid or jelly etc. in the vessel I I2, the membrane I, the wire IIS., the insert extension IIS, the'walls of the guide channel in which the eX- tension II9 is inserted, the wire I2I that is connected at the left side of battery 68.

The person speaking against the diaphragm |01 brings the same thereby into vibration and these vibrations are transmitted to the metallic membrane III by means of the wire or bristle I |0. The gas or fumes or other mentioned matter contained in the vessel II2 takes up the vibrations made by the metallic membrane I I I and since electric current flows at the same time through the metallic membrane II I and through the fumes or gas or liquids etc., the Vibrations will thus be rendered into electric impulses, which the plate II 6 takes up and imparts to the primary winding 6| through the wires II5, II8, the insert extensions H9, |20 and the contacts in the connecting part 61, the battery 68 and the

wires

64, 65. The secondary winding 62 still more clarifies the impulses and if the connector |23 is in closed position, conversation can then be had with the connecting station and when the operator cc-nnects with the number that is demanded, conversation will then be had with the party whose telephone is thus connected.

The secondary winding 62 is in electrical connection with the connecting station shown in Figure 4 or Figure 15 or Figure 16 and has similar `connections as has been explained in connection with the Figure 10.

In order to make the mouth piece of Figure 11 as light as possible so that it can be carried4 in the pocket of its owner, the connector is not incorporated with the mouth piece, but is brought in connection with the conductor |22 and is indicated by |23. For connecting the mouth and ear piece at such places that are remote from the home or olce the conne-ctor will not be needed, since electric connection will be established with the connecting station at the moment the inserts are inserted in the guide channels.

Having described the details of some preferable types of the receivers and transmitters it is to mention that the non-metallic diaphragms are greatly advantageous for the transmission and reception of the amplified voice. This permits again the installation of amplifiers of the radio type at the connecting stations (see Figures 4, 15 and 16) where the electric impulses coming over the wire will then be amplified upon request. Various forms are thus adaptable. In one form shown in Figure 4, the operator at the connecting station disconnects the contact I1 from the contact I6, but closes the switches |32 and |33. Through this action the wire 54 or |22' will be brought into electrical connection with the amplifier B andthe wire I3 will be electrically connected to the amplier C. If the caller at the transmitter that is connected to the wire 54 or |22 requests that the operator connects the amplifier and tunes it up to the desired volume, the electric impulses set up in the wire I3 and the secondary winding of the transformer, that is in electrical connection with the wire I3, thus will be amplified in the amplifier C, and in such state the electric impulses will be impressed uponY the wire 54 or |22 and consequently the electromagnet 4, 5 or 34, 35 of the receiver'vibrates the diaphragm in .such degree that the voice produced thereby is in intensity above the voice that is derived from electrical impulses that did not receive amplification. On the other hand the wire 54 or |22 that is in electrical connection with the amplifier B might also have the electrical impulses amplified if it will be so requested from the party at the receiving end of the wire. If no such request will be made, then the amplifier B will be tuned only to such degree in which the electrical impulses originated by the transmitter in connection with the Wire 54 or |22' and the respective secondary winding thereof of the transformer will be transferred without amplification upon the wire I3 and the electromagnets 4, 5 or 34, 35 in about the same degree as they are produced in the wires 54 or |22. The circumstance, that the party listening at the receiver at the end of wire I3 will hear its own Voice amplified, makes it the-n necessary to cover the front side of the ear piece, in any suitable way, while transmitting, that is, speaking into the transmitter; or the ear piece may be simply held away from the ear.

This inconvenience, which is caused by the amplication of the electric impulses set up in the wires 54 or |22 and transferred through the amplifier B to wire I3 and the receive-r at the other end, can be remedied when a special wire |34 (see Figure 15) will be connected to the secondary winding of the transformer of the transmitter T, whereby the wire 54 will be connected to the receiver R. only.

By separating the amplifier D completely from the wire 54 and connecting the wire |34 to the amplifier D by means of the switch |32 amplification will be had in the receiver RI, over the wire I3. If the party at the receiver R wishes to have also amplification of the words coming over the wire, the operator, when thus informed, disconnects then the contact l1 from the contact I6 and closes the switch |33'. The Words spoken into the transmitter TI will be amplified by the amplifier E and in such amplification will be had at the receiver R. In order that the own words will not be heard in the receivers by the person speaking into the transmitter T or T', the `switches |34', |35 should be opened.

A simplification of the system, shown in Figure 16, is that only one wire leads from the receiver R2 and the transmitter T2 to the connecting station F and also only the wire |3" from the receiver R3 and the transmitter T3 to said connecting station F. In order to avoid that the own words will be heard at the receiver by a person speaking into the transmitter not to say the amplified voice, there is a system of 'very sensitive relays employed that act at the slightest electrical impulse that energizes the cores of said relays. For simply connecting the telephones of two parties that wish to have conversation with each other the contact (the insert or switch plug) is to be inserted into the contact |6. The party using the receiver R2 and the transmitter T2, wishing to have the words amplified that come from the connected phone with the receiver R3 and transmitter T3, order so from the operator at the connecting station F. The operator pulls then the switch plug |1'out of the contact I6 and closes the switch |31. Electric connection is thus established between the receiver R3 and transmitter T3, on the one hand and the amplifier G, on the other. It must be remembered that the armature |43 normally is in its dropped position in which it contacts with the contact |44. The amplified electric impulses are impressed upon the winding of the relay |39 by the wire |38. 'Ihis relay attracts thereby its armature |40 and the latter becomes thus disengaged from the contact |4| of the lead |42 that leads to the amplifier H. The amplied electric impulses thus cannot ow to the amplier H and are forced to concentrate -on the receiver R2 and the secondary winding of the transformer |45 that is grounded at |46. The electromagnet 4, 5 (or 34, 35) in the receiver R2 vibrates the diaphragm 3, 30), commensurate with the degree of the electric impulses, which it receives, and sin-ce they are then amplied, the voice, created by the vibrations of the diaphragm, is then also commensurately amplied.

. multaneously with the The armature |40, being thereby disconnected y from the contact I4|, no sound, that was spoken into the transmitter T3, will be heard amplified at the receiver R3.

The party at the telephone with the receiver R2 and transmitter T2 must also be able to communicate (speak) with the party at the phone with the receiver R3 and transmitter T3; therefore, as soon as the armature |40 drops electric connection is established with said party at the right, namely the phone with the receiver R3 and the transmitter T3. The electric connections, include the wire |42, the amplifier H, which, however, is tuned only to the degree which will produce a sound at the receiver R3 that equals that which is obtained when no amplification will be had, that is, when the contact |1 is simply connected to the contact I6. The relatively weak electrical impulse is adapted to energize sufficiently the core of the relay |49 so that the armatures |43 and |50 will be attracted and an electric connection with the receiver R3 and the secondary winding 62 of the transformer 63 is established, whereby said secondary winding is grounded at |55.

If the party at the telephone of the receiver R3 and transmitter T3 wishes to get also amplification and noties the operator at the connecting station F, the operator simply tunes up the amplier H to the desired volume. The amplication will be impressed upon the lead |48, the winding of the relay |49 and since the armatures |43 and |50 are attracted thereby connection with the ampliiier G and conductors associated therewith will be severed, but electric connection with the receiver R3 and the secondary winding 62 and ground |55 (transmitter T3) established. The party at the phone of the latter receiver and transmitter will thus have amplification in the desired degree without having its own words amplified at the receiver R3 that are spoken into the transmitter T3.

A still greater simplication consists, in using only one amplifier, as for instance'the one indicated by G. In this event ;the switch plug (contact) I1 is to be contacted with the wire |52 or directly with the proper contact of the amplifier G. A wire is then to be connected to the wire |38 and to the winding of the relay |49. Amplification, however, will be had at the receiver siown words spoken in the transmitter.

The system illustrated in Figure 15 might vbe advantageous with connections in which relatively little wire will be needed as, for instance, when it deals with an installation that is limited to the home, an estate or to a factory or to some not too far distanced or neighboring buildings only. The system contemplated in Figure 16, however, is more adapted for longer distances and long distance calls, since only one wire is needed to connect the receiver and transmitter with the connecting station, the central station, respectively. There is at least one great advantage in connection with the ampliiiers that are situated at the connecting station only, because the necessary care and correct handling and better protection of the same is thus assured and not many amplifiers might be needed.

Referring to the transmitter of Figure 11 there is also a standard |31 contemplated that is indicated by dotted lines. Since the structure and shape of the mouth piece differs from that of Figure 10 a method is therefore adaptable in which by means of hooks 38, |39 the mouth piece will be held in vertical position, which is the position in which the diaphragm is also vertical. A spring |40 will urge the hook |39 against the hull 29 and the springy part |4| will pull the hook |38 and consequently the upper part of the hull 29 against the standard |31, permitting at the same -time the separation of the hook |38 from the hull 29 and the latter from the hook |39 and then of the standard |31. The latter may also have al1 the improvements which are, for instance, known with standards of microphones.

Referringto Figure 12 the scheme employed might nd as well use with the disclosure of Figure 9 or even with that of Figure 10. It consists of placing carbon granules |43' or graphite or charcoal or a mixture of these ingredients-in the space, situated between the metal membrane |44' and the metallic wall |45', which is in electrical connection with the primary winding of the transformer, shown only in Figures 10 and 11. The membrance |44' will be Vibrated by the diaphragm |46', its attached part |41', respectively, whereupon the granules |43 transform the Vibrations into electrical impulses. In connection with some of the receivers, especially those that have cone shaped diaphragms, as, for

instance, shown in Figure 6, the pole ends of the cores of the electro-magnetl may consist of two or more branches when it deals with cores that must be close to parts of the diaphragm that vibrate the most violently. One branch 8 end may thus face the part of the diaphragm that is half Way between the outer frame and the center point, the apeX of the diaphragm, and the other somewhat nearer to the apex, as also shown in Figure 6. The former may, however, suflice in this case.

summarizing the invention, first, the diaphragms of the receivers as well as of the transmitters are contemplated to be of other materials, chiefly fibrous materials, than of all metal, because the atomic structure of metals is not so favorable for giving the membranes, made of metal, the relatively wide range of vibration which is, however, inherent with the materials contemplated in the present invention. The means for coating the diaphragms, of which lacquer, or a certain kind of varnish is contemplated, protect the diaphragm as it gives also the vibrating quality to it when in dry condition.

Therefore, through the addition of iron filings in the lacquer that covers said non-metallic material of the core of the diaphragm of the receiver and especially the side of the core and only the area that faces the poles of the electromagnet, the electromagnetic impulses will be transformed into sound vibrations.

Further, a system is created in which thanks to the non-metallic diaphragm, being adapted to increase the sound vibrations and thus increase the volume of the voice caused by the electrical impulses sent over the wire, the decrease of the size and weight of the ear and mouth piece is thus permitted.

Furthermore, the forming of the ear and mouthA pieces as detachable parts that can be used as the personal ear and mouth piece and which are adapted to be carried in the pocket or in a hand bag, when not in use, is one of the results.

Furthermore, the ear and mouth piece (the receiver and transmitter), through their wider range of vibrating movement, permit the ampliiication of the electric impulses set up and the commensurate amplification of the sound with the receiver, the ear piece.

Furthermore, since amplification should be made only when so ordered, the system comprises therefore such connections and apparatus that permit amplification only for the party, asking for it, whereby amplification will be had in the desired volume for all, that is the two parties speaking together over the telephone, if so rdered and the connections are made.

Furthermore, thanks to the proper arrangements of the electric connections and certain other means of one simplified embodiment, the words spoken into the transmitter by a person will not be heard in amplified volume in the receiver to which listens that person.

Furthermore, the system comprises also such other electric connections in which the words will not be heard at the receiver at which the person listens that speaks them into the transmitter.

Furthermore, such simplified electric connections are also devised which, however, amplify the words spoken into the receiver if such ampliiication is demanded, whereby the words spoken into both transmitters will be heard in amplified volume at both receivers.

Furthermore, the fact that the transmitter and receiver can be detached and carried on the person that possesses them, permits the installation of contacts with electric connections leading to the connecting station, whereby these contacts do not need to be confined solely in telephone booths, in which, however, they may be arranged also.

Furthermore, the creation of new means for the transformation of the sound vibrations into electrical impulses favor the clear and voluminous transmission of the voice and favor also the amplification thereof.

Furthermore, the addition to the diaphragm of the transmitter of iron filings for synchronization with the diaphragms of the receivers.

Furthermore, the creation of the cone shaped diaphragm and of the fiat diaphragm.

Furthermore, the creation of a handy dish-like part on which the light and handy ear and mouth pieces can be placed so as to be ready for the use at any time.

, Furthermore, the use of liquid and semi-liquid or jelly like means for the transformation of the sound vibrations into electrical impulses.

Furthermore, the use of metal wool for the transformation of the sound vibrations into electrical impulses.

Furthermore, the arrangement of fine springs for the transformation of the sound vibrations into electrical impulses.

Furthermore, the transmission of the vibrations of the non-metallic diaphragm upon a metallic membrane.

Furthermore, the disconnection of the battery, the primary and the secondary windings of the transformer from the transmitter, thus permitting the latter to be very light and adapted to be carried on the person when not in use, and coni sequently the confining of said battery and transformer at the places with the stationary contacts or at the connecting station whereby only few batteries and transformers will be needed for a large number of stationary contacts, that offer the contacting of said transmitter as well as the receiver and therethrough the electric connection with the connecting station.

Furthermore, electro-magnets having cores, the pole ends thereof may be branched.

What is claimed is:

1. A telephone transmitter and a receiver, the latter associated with an electro-magnet, both. the transmitter and receiver, having a diaphragm of non-metallic material, the diaphragm consisting of a core held by stretching means in such position that it assumes the shape of a cone, and both cores of the diaphragms lacquered and at least the diaphragm of the receiver having iron filings embedded in the lacquer at the parts of the diaphragm only that are distant from said stretching means and facing the poles of said electro-magnet.

2. A telephone transmitter having a non-metallic diaphragm, a part secured to the latter and touching a metallic electrical conducting part of flexible property, and other metallic means of flexible property touching said metallic electrical conducting part, and both said metallic electrical conducting part and said other metallic means adapted to vibrate in unison with said diaphragm, and said metallic means in connection with an electric circuit, transforming the vibrations into electrical impulses.

3. A telephone transmitter, a diaphragm of non-metallic material, comprised in said transmitter, the diaphragm lacquered and iron particles embedded in said lacquer, a membrane of metal, a stiff and light part secured to said diaphragm and having an end, the latter normally touching slightly the membrane of metal and impulses and impress the latter upon other-electrical conductors inclu ng a transformer. i

4. A telephone transmitter, a diaphragm of non-metallic material comprised in said transmitter, the diaphragm lacquered, a membrane of metal, a light means secured to said diaphragm and touching lightly said membrane of metal and adapted to transfer the vibrations of said non-metallic diaphragm upon said membrane of metal, the latter connected in an electric circuit, a vessel of insulating material, said membrane covering part of said vessel, the latter containing gaseous matter that is adapted to take up the vibrations of said membrane of metal and impress them upon other electrical conductors, including a plate and a transformer, in form of electrical impulses.

5. A telephone receiver and transmitter, adapted to be carried in be connected and disconnected from contacts that are in connection with the stationary circuit connections of the connecting station, a dish-like part permitting the placing upon it said receiver and transmitter, a standard adapted to hold said transmitter and a standard to hold said receiver in the vertical positions.

6. A telephone receiver and transmitter, a dishlike part adapted to receive said receiver and transmitter for the handy handling thereof, said dish-like part having a part consisting of electrical contacts and the latter included in an electrical circuit that includes also a means for announcing a call, one of said electrical contacts adapted to disconnect itself from the other when said receiver is taken from said dish-like part, thus opening the circuit in for announcing is included, same in its function.

7. A telephone receiver and transmitter, stationary circuit connections of a telephone system, including electrical connecting parts at various locations and some including a cord with electrical conductors, the transmitter having electrical connecting parts and adapted to be electrically connected to said electrical connecting parts that include the conductors in said cord, a push button adapted to stay in the pushed-in position and thus make an electrical connection that closes the circuit in which said transmitter is included, and another push button for pushing the rst mentioned push button out and in circuit disconnecting position.

8. Stationary circuit connections and a connecting station of a telephone system including electrical connecting parts at various points, a telephone receiver and transmitter having connecting means for the electrical connection with said electrical connecting parts and adapted to be electrically connected to said electrical conparts every time a telephone call is to and likewise to be detached from said electrical connecting parts every time the telephone call is finished and adapted to be carried in a pocket or in a hand bag, the transmitter comprising circuit closing and opening switch means, said switch means adapted to let the calland thus stop the er make electrical connectionl with said connecting Vstation at anytime after circuit connections;

9.Y A telephone a predeterminedvalue is inserted. Y l

10. A telephone system comprising a connecting station with an in the electro-magnet of that receiver, and said electric impulses may be amplified by an amplifier at said connecting station.

11. A telephone ing station and electric conductors leading theretro-magnets into sound, increasing and decreasing it in intensity commensurate with the insys/tem comprising a connecting statlon and electric conductors leading to vari-vV lring station and means crease and decreaseA of the electric impuls-es set up in the conductors that are in electrical connection with said electro-magnets, an amplifier at said connecting station, electrical conductors leading from every transmitter to said connectfor connecting them to said amplifier, separate electrical conductors leading from said receivers to said connecting station and means for connecting them to said amplier, in such way, as to receive the output of the amplified electric impulses set up in the electrical conductors oi said transmitters, means for electrically connecting the electrical conductors of one of said receivers and of one of said conductors that will be at hand at any of said points and thus permit'the connection by means of known contacts of two telephones of parties that want tov have conversation together without said' electrical conductors being then in electrical connection with said amplifier and consequently. without amplification of the sound produced by the transmitter.

12. A telephone system comprising a connecting station and electric conductors leading therefrom to various points including also telephone booths, receivers and transm'tters at said points and electric contacts for the insertion of contacts ofY detachable receivers and transr'nitters',A the receivers' comprising electro-magnets and diaphragms, the latter adapted to transform the' magnetic impulses, setY up in said electro-mag-r nets, into' sound, commensurate with the intensity of said magnetic impulses,` an amplier at said connecting station and connecting meansfor simply electrically connecting two of saidY electrical conductors,r connecting means for connecting one of said electrical conductors with said amplier and a relay the winding of which is in electrical connection with the electrical conductors that receive the output of said amplifier, a contact of said relay and an' armature thereofV normally contacting with said contact, another amplifier, said contact electrically'connected-with. said other amplifier another relay, the winding of the latter electrically connected with said other amplier and adapted to interrupt at times' one of said electrical conductors and at the same time to establish electrical connection with said other amplier and with the receiver and transmitter in 'connection'Y with said last mentioned electrical conductor, so that the output of said other amplifier. reaches the last mentioned receiver.

HEINRICH KARL.