DE118874C - - Google Patents

Description

IMPERIAL

PATENT OFFICE.

PATENT LETTERING

- M 118874 CLASS 21 a.

connected telephone stations.

Patented igoo in the German Empire from March 8th.

In the patent specification 108993 a method for telegraphing between two by an exchange with interconnected telephone stations has been described, in which the current surges used for the formation of symbols through the magnetic inductor of the Telephone set. To prevent disruptions in the switching office, where the magnets of the call signs are provided with polarized anchors, special devices must be provided, by which 'only one-way telegraph currents sent over the telephone line can be.

According to the present invention, by using a local battery 'in connection with an inductorium for generating the current impulses used for telegraphing, the above-mentioned devices come in omission by then only the opening of a local circuit in the secondary electric circuit induce current surges, which because of the polarized armature of the call sign magnets in the central office can cause no disturbance, are strong enough to power the telegraph receiver to put into action. The induction role of the Microphones are used to generate the electricity necessary for telegraphing.

This arrangement is shown in the accompanying drawing. The microphone inductor is labeled 50, 51 is the telegraph inductor and 52 is the microphone and telegraph battery, 53 is one for moving two power switch levers 54 and 55 serving telegraph key. These two Stromschlufshebel 54, 55 are so with the Lever 53 connected so that they can be moved simultaneously by the same. Of the Lever 54 can in this way with one or the other of two Stromschlufsstücke 56, 57 and the lever 55 with one or the other of two Stromschluisstücke 58, 59 are brought into contact. The arrangement is such that the lever 54 can be Stromschlufsstück 57 does not go before the Stromschlufs has been interrupted at 59. The levers usually take those shown in solid lines in the drawing Layers.

The calling device can conveniently be placed on line 60. if now the subscriber 101 calls, the current from the call set takes the following course: Via lineöo, microphone inductor5o, contact 56, coils 9 and via the line to the Switching office o, which manages the calling of subscriber 102 in the usual way and establishes the connection between the two participants. When the subscriber 102 is called by subscribers 101 the call flow will proceed as follows: From the line through the Coils 9 of the alarm clock, via the contact 56 through the remote receiver, the secondary winding of the microphone inductor 50 and

tion 60 to earth. Here, of course, the alarm clock works as usual, and there while calling the anchors 16 for both the calling party and the called party is attracted, the local circuit is indeed via the telegraph receiver 67 kept closed as long as the calling lasts; but this does not result in any disturbing sign formation, since only a single closing and opening of the local circuit takes place.

If the called party (102) is absent, the calling party (ιοί) can accomplish the telegraphy by moving the key 53 back and forth without any other measures. When the key 53 is moved to the left and the electrical connection pieces 57 and 59 come into contact with the levers 54 and 55, the local battery 52 comes into effect, and, as can be seen, in such a way that the local current flows through the primary winding of the telegraph inductor 51 will go (52,73,72,55,59, 61,51,62,65,52). Both when this current is closed and when it is subsequently opened, a current is produced in the secondary winding of the telegraph inductor. As can be seen, these currents go from earth at caller 101 via 60, 51, 57, 54, 9, office, 9 to subscriber 102, via 54, 56, remote receiver, 50, 60 to earth at called 102 and from here to Caller 101 earth back. Of these induced Stromstöfsen the while Reasoning evoked known to be very weak and therefore exert a disturbing effect ^one from either the Vermittelungsamt nor the called party; the induced current surges produced when the local current is opened (in the opposite direction), on the other hand, are strong enough to attract the armature 16. This closes the contact 63, 64 and thus closes the local battery 52 via the telegraph apparatus 67. This local current has the following course: 52, 73, 72, 71, 64, 63, 16, 68, 67, 66, 65, 52.

So that the end of the telegraph ^{1 can} receive a copy of the dispatch, the coils 9 of the alarm clock are constantly switched on in the voice line, even when the receiver is lifted. This makes it possible for the end of the telegraph to hold his receiver to his ear even while the telegraph is being made, which can often be desirable. The switching arm 66 is used to switch off the receiver apparatus if the sender does not wish to receive a copy of the dispatch.

Instead of the alarm clock magnet it can be used as a normally open contact for the telegraph circuit also a special relay can be used, the armature and Stromschlufsfe'der very be designed to be easily movable and possibly housed in an empty container can be.

Claims (1)

Patent claim: Procedure for telegraphing between two through an exchange office with each other connected telephone stations, characterized in that, in order to avoid disturbances in the central office to be able to prevent such surges from being used for telegraphing, by means of a local battery and an inductorium in the secondary line "des the latter and in the telephone line, from which electrical surges as is well known, those who are induced when the local circuit is closed are very much are weak, so that they are neither in the switching office nor in the telephone of the person called Participant can exert an effect, while those current surges that occur during Opening of the local circuit are so powerful that they affect the receiving apparatus can put into action. 1 sheet of drawings.