DE194722C - - Google Patents

Description

IMPERIAL

PATENT OFFICE.

PATENT LETTERING

- M 194722 - CLASS 21 a. GROUP

Patented in the German Empire on December 23, 1905.

The invention relates to telephone systems equipped with main and branch exchanges according to the so-called final sign system, in which one is placed on the office Battery is only used to power the final sign and, similar to central battery systems, one on the Auxiliary relay at the main station, fed by a local circuit, at the MeI-dung the main office makes the final sign on the office disappear. The help relay is also used for the aforementioned purpose In the present invention, this is also the case when the telephone is attached to the extension to bring the final signal to appear again on the office. According to the invention this is achieved by the auxiliary relay when the main unit is switched on to the exchange line initially via the normally closed contacts to switch on the extensions Serving switching devices is energized and then up to the notification of the extension about his armature is kept energized, however after reporting the extension in known Way is de-energized and thereby a bridge containing a final symbol over a in the forms a voice line, impermeable to direct current, so that At the end of the conversation, a current flows through the armature of the auxiliary relay, which brings the final sign to appear on the office.

In the drawing, an embodiment of the new circuit is shown.

The cord system of office A has a battery a, an induction coil b and terminating characters d, d ¹ bridged by a capacitor c . The call sign e is in the bridge between the trunk lines ι, 2 and is switched off when the plug is plugged.

The main unit B is equipped with five push-button switches f, g, h, i, k , of which f to connect the main unit and office, g to switch on the interrogator g \ h to switch on the inductor h ^l and i, k to switch on the auxiliary units C, D serves. The main station also has a terminator m, an auxiliary relay n, a battery o, a capacitor ρ and the call signs A \ C \ D ¹ assigned to the office A or the branches C, D. The microphones of the interrogator g ¹ and the extensions C, D are fed by special local batteries. The extensions are switched in such a way that in the idle state

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Electricity can flow through them during the Conversation, however. The circuit of the other devices is shown in the drawing.

For example, if exchange A wishes to connect to extension C, the plug q is inserted into the jack r, so that current flows in the following way: free pole of a, d, neck of q, long spring of r , i, / ⁵ , / *, A \ / ³ , / ² , 2,

ίο short spring of r, tip of q, b, earth pole of a. The signal A ¹ responds. This alerted the officer to switch / and g on main office B, connecting the main office to the office through the former and at the same time switching off signal A ¹ , and switching on her interrogation apparatus g ^{l through the latter.} When the switch / is turned, its springs / ⁷ , / ^{8 come} into contact so that the auxiliary relay η receives current in the following way: Free pole of 0, n, / ⁸ , f, 3, V, ■ i ⁸ , k \ k ^s , earth, earth pole of 0. The two armatures n ^l and w ^{2 of} the relay η are thus attracted. By flipping the switch / the circuit of the office battery a specified above is interrupted. From the line 1 there is now a ^{direct current connection via / V / 6} to the final character m ; however, its other pole is without a connection ^{in the working position of n 1.} The final character d on the office disappears.

After the officer of main office B has learned that a connection with extension C is to be established, she puts switch g back, switches h and i and, by turning inductor h ^1, calls extension C by means of current h ^l , left-hand side Springs from / z ⁵ , z ' ^e , z ⁵ , C, z' ² , i ¹ , /? ⁴ , right-hand springs from / z ⁴ , h ^l on, so that the alarm clock sounds on this. By flipping the switches h and i , the contacts h ⁷ , h ^s in, and the contacts z ' ⁷ , z' ^{8 come} out of contact. As a result, the above-mentioned circuit of the auxiliary relay η is interrupted, but it remains live in the following way: Free pole of 0, n, n ¹ , 4, h ^s , h ⁷ , 5, M ² , earth, earth pole of 0, see above that the anchor n ^{ remains in the working position and the final character d cannot appear again on the office. Even after the switch h is back, the relay η remains energized via n ¹ , 4, h ^ä , h *, i ^[ , z ² , extension C, z ' ⁵ , z' ^e , 5, n ² , except for Extension C of the remote receiver is removed from the hook switch and this intercom is locked against direct current. Now the auxiliary relay η drops its armature; but even now he cannot do the final character d on the office

seem, because there is no direct current path from line 4 to trunk line 2 or to earth. Rather, this is only formed when the remote receiver is hung back on extension C after the call has ended. Current then flows in the following way: Free pole from a, d, neck from q, long spring from r, i, / ⁵ , / ⁶ , m, n \ 4, h ^s , h \ i \ i \ C, z ⁵ , z ^e , 5, 6, f ¹ , / ² , 2, short spring of r, 70 tip of q, b, earth pole of a. The final character m appears on the main point B and at the same time the final character d on the office A.

The extensions C, D call the main unit B by means of their inductors C ² , D ² , whereupon the signals C ¹ and D ¹ appear, and the main unit B calls the exchange A after flipping the switch g and / via the contact springs / ⁶ , / ⁵ , / ² , f ¹ and the lines 4, i, 2, 6 by means of the inductor g ² , whereupon the signal e appears. The resulting currents as well as the course of the speech currents in the various connections are readily apparent from the drawing; therefore, and because they are irrelevant to the essence of the present invention, they should not be specified in more detail. It should only be noted that the inductors g ¹ , C ² , D ² are set up in a known manner in such a way that they are usually open and only switch on when the crank is turned. If one of the extensions C, D or the main office B is connected via the exchange A , the 95 speech currents take their way via the capacitor ρ of the main office B and the capacitor c of the exchange A.

Of course, any number of extensions can be connected to main office B. ioo

Claims (1)

Patent claim: Circuit for telephone systems according to the closing signal system with main and secondary units, in which an auxiliary relay located on the main unit and fed by a local current makes the closing signal disappear when the main unit reports a call from the office, characterized in that the Auxiliary relay (s) when connecting the main unit (B) to the _{exchange line r} (i, 2) initially via normally closed contacts (i ⁷ ; i ^s , k "", k ^B ) of the switching devices used to connect the auxiliary units (C, D) (i, k) is excited and then via its two attracted armatures (n \ n ² ) and the connected, but still in the idle state of secondary place remains excited, while in a known way it is de-energized again when the latter is reported and thereby forms a bridge containing a final character (m) over an organ (p) which is in one voice line (i, 4) and is impermeable to direct current, so that after termination of the call by the extension of the available on the exchange office (a) battery (a) (d, m) is a current flow through the clearing signal takes on the office and the main office concluded. 1 sheet of drawings.