DE621922C - Circuit arrangement for starting up amplifiers to be switched on in signal or telephone lines - Google Patents

Description

GERMAN EMPIRE

ISSUED ON NOVEMBER 15, 1935

REICH PATENT OFFICE

PATENT LETTERING

CLASS 21a ³ GROUP 57

General Electricity Society in Berlin *)

amplifiers to be switched on

Patented in the German Empire on October 11, 1931

In signal and telephone systems, there are often amplifier tubes in the receiving stations arranged, which the currents transmitted on the transmission line, which are intended for the receiving station concerned, strengthen. With amplifiers of this type, the input tubes were always kept in To keep operation if the receiving station in question is always ready to receive should. In the event that the amplifiers do not need to be permanently operational, one has already created facilities in which the commissioning with the help of preparatory power surges.

While the known devices with constantly operational amplifiers the Had the disadvantage that the life of the amplifier tubes is very short, they have known devices with remote-controlled activation of the amplifier tubes have the disadvantage, that special receiving devices for receiving the unamplified inrush currents required are. The main disadvantage of this device is that continuous operation of the Transmission system is not possible.

The invention consists in that the hot cathode of the input tube in regular recurring sequence is brought to their emission temperature and the preparatory current surge is so long that during its duration the hot cathode reaches its emission temperature at least once. As soon as it does, speak the input tube on, and it is excited, for example by an anode current Relay, the hot cathode heating switched on, until the signal or voice transmission is finished. After the completion of the transmission it will revert to the intermittent one Heating of the hot cathode passed over until there is a new distant signal and a new transmission process. That Ratio of the heating duration of the hot cathode to the duration of the interruption can Chosen at 1: 5 or 1: 10 without difficulty will. This significantly increases the service life of the input tubes.

Some embodiments of the invention are and are described below shown schematically in the drawing. Fig. Ι a relates to long-distance transmission of a signal. Fig. Ib is a diagram showing the operations of the Fig. Ι a included relay can be easily followed. Fig. 2 shows a circuit arrangement for the entrance tube of a tele-

*) The patent seeker stated that the inventor was:

Dr.-Ing. Ernst Sommerfeld in Berlin-Tempelhof.

Talking station, Fig. 3 also shows a circuit arrangement for a telephone station, whereby it is presupposed that, in addition to the one shown in Fig. 3a, there are several other stations in the system that are to be called optionally. Fig. 3b shows 10 after the in fig. 3 a shown station transmitted dial pulses and the corresponding pre-signal in Fig. ι. a represents the input tube 11, a circumferential contact device, each of which includes every 8 seconds for 1 second heating circuit of the hot cathode. a and B two relays, the excitation windings of which are connected to the anode circuit of the tube 10. A ' is a self-holding winding for the relay A. E and C are two delay relays, of which the first has a response delay, the second a release delay, as shown in the drawing a wing attached to the armature and an arrow in the direction of the delayed armature movement is indicated, the arrangement of the contacts of these relays and e Another relay D can be found in the drawing. The signal receiving apparatus is denoted by 12.

As long as no signal or distant signal is transmitted on the long-distance line, the contact device 11 closes the heating circuit of the hot cathode for 1 second every 8 seconds. However, there is no change in the excitation of relays A to D and consequently in the position of their contacts. When the apparatus is in the idle state, the contacts are in the position shown in Fig. 1 a; the position shown in dotted lines applies to the contacts e _i} e _2. If a signal transmission is to take place after the station, a current surge is transmitted on the long-distance line, which has about the duration of the period of the hot cathode heating. In Fig. 1 b, the course of the heating current over time is shown on the top horizontal line. The heating takes place every 8 seconds and lasts 1 second each time. On the second horizontal line, the pre-impulse of 8 seconds duration is shown. He may begin in the heating pause once then the contact device 11 includes the so-heating circuit, namely at time t _x, flowing in the anode circuit of the tube 10 current and the relays A and B are excited. The relay A closes its normally open contact a _lt which the contact device 11 over-55 ^{: bridges.} The hot cathode heating therefore remains switched on as long as the contact Cf _{1 is} closed, even if the contact device 11 opens again. Relay B , which responds at the same time as relay A , closes its normally open contact b _± , which causes relay C, which is equipped with drop-out delay j, to respond; it also opens its normally closed contact b ₂ , which is initially irrelevant as the excitation circuit of the Relay D at contact C ₁ is still open anyway. Furthermore, the relay B closes its normally open contact b ₃ in the actuation circuit of the signal receiving device 12. However, this is of no significance since this circuit is _{open at the contact d 2.} The last contact of relay B, the normally closed contact b ₄ , opens the excitation circuit of relay E, which has a response delay of 4 seconds, as shown on the third horizontal line in Fig. Ib, but no drop-out delay. The _{normally open contact a 2} closes the circuit of the self-holding winding A ', which is routed via the normally closed contact B _{1 of} the relay E. Its normally closed contact e _{x also} closes at the time t _lt so that the self-holding winding A'_ of the relay A contains current. The closure of the normally closed contact e ₂ is also initially of no significance. At the end of the pre-signal, ie at time t ₂ , relay B drops out, relay A remains energized via its self-holding winding A '. Relay B opens its normally open contact b _lt relay C however, only drops with a certain delay as to the lowermost horizontal line of Fig. Shown b1. Contact C ₁ accordingly remains closed beyond time t ₂ and may not open _{until time i 3.} The normally closed contact b ₂ is already _{closed at Zeitt 2} , so that the relay D is energized, which in turn holds itself via its normally open contact d _± and via the normally closed contact e _{2 of} the relay E. The excitation of the relay D at time t _{2 also} causes the normally open contact d ₂ to close, which, however, initially also does not cause the signal reception to be actuated in front of device 12, since contact b _{3 has} already been opened again at time t _2. By closing the normally closed contact Zj ₄ , the relay E is energized and its delay time starts again. The closing of the contact device 11, which occurs again at the time t _s , is of no significance, since the contact device is bridged _{by the normally closed contact O 1.} At time i ₄ , the transmission of the current impulses intended for controlling the receiving device begins on the long-distance line. At the time i ₄ , the relay B is excited again, _{the normally open contact O 1} and the normally closed contact & o are closed or opened. The closure of contact b _t causes relay C to respond again; however, the closure of its normally open contact C _{1 has} no effect on the energized state of relay D , since on the one hand the idle

contact b _{2 is} opened and on the other hand the relay D is already excited via its normally open contact (I ₁ and the normally closed contact e _2. The normally open contact d _{2 of} the relay D is and remains closed. By closing _{the normally open contact b 3} , the receiving device 12 a current surge is supplied, the duration of which, as shown on the second horizontal line in Fig. 1b, may be ίο 10 seconds. At time t ₅ the current surge is ended, the normally open contact b _s opens again, and the receiving device 12 is de-energized. It now shows the transmitted signal. At the same time the normally open contact b _lt opens again and the normally closed contact b ₂ closes. For the reasons already mentioned above, this again has no effect on the relay D. By closing the normally closed contact b _i , the delay relay E is excited again, so that after its delay time has elapsed, namely at Zeit.i ₀ , the normally closed contacts e _t and e _{2 are} opened When the former is opened, the holding winding A 'of the relay A is de-energized, so that the normally open contact O ₁ is opened again and there is again a transition to the intermittent heating of the hot cathode. By opening the normally closed contact e ₂ , the hold circuit of the relay D is interrupted, so that this relay drops out again. This means that all contacts are in the position they were in before the distant signal began.

In Fig. 2, which shows a telephone station that is only connected to a single remote station, the input tube and the contact device in the heating circuit is again designated by 10 and 11, respectively. A relay arranged in the anode circuit is designated with F, its normally open contact with f ± . In addition, the primary winding of a telephone transmitter 13 is switched into the anode circuit, the secondary winding of which leads directly or indirectly to the hearing microphone. The excitation winding of a bell 14 is connected _{in series with the normally open contact Z 1} and a contact A ₁ , which latter may be closed as long as the handset rests on the cradle of the telephone set, i.e. as long as the called station has not yet answered. The contact device 11 is a contact A ₂ parallel, which is also attached to the fork of the telephone set and which bridges the contact device as soon as the receiver is picked up. As long as the telephone station is not called, the contact device 11 intermittently closes the heating circuit, but provided that no voltage is supplied to the grid of the tube 10, the relay F remains de-energized. If the station is to be called, voltage is applied to the remote line at the opposite station, and when the contact device 11 is next closed, current flows in the anode circuit of the tube 10 and the relay F is energized. By closing its _{normally open contact Z 1} , the bell 14 is actuated as long as the contact device 11 is closed. After the contact device 11 is opened, relay F drops out and the bell signal disappears until the contact device 11 closes the heating circuit again. If the receiver is now lifted in the called station, the normally closed contact A _{1 is} opened and thus the circuit of the bell 14 is interrupted and the contact h _{2 is also} closed and thus the hot cathode of the tube 10 is continuously switched on. The speech streams arriving on the long-distance line are now, after they have been amplified in the input tube 10, directly or indirectly fed to the ear microphone via the transmitter 13. If the speech currents cause a short-term or permanent excitation of the relay F , the bell does not sound because the _: fork contact A ₁ interrupts the excitation circuit of the bell during the call. When the receiver is replaced, contact A _{1 is} closed and contact Ji _{2 is} opened. This goes back to intermittent heating of the input tube; the telephone station can then only be called again by a new pre-pulse of the corresponding length.

In the circuit according to Fig. 3a it is assumed that, in addition to the telephone station shown, there may be other stations in the system which, in addition to the one shown, can optionally be called _1O o. The input tubes and the contact device are again designated by 10 and 11, respectively. In the anode circuit of the input tubes, the relays A and B are as in Fig. IA and the transformer 13, as in Fig. 2 _lt> 5 discussed. There are again a self-holding winding A 'and two relay E and C is present formed from similar reasons as in the device according to Fig. 1 a, further comprises a bell 14 undeinTelephoniewähler 15 whose no rotary magnet by the relay C. A relay D is connected in a contact of the selector 15.

As long as the telephone station in question has not been called, all relay contacts are in the position shown in Fig. 3a. For contacts e _t to e ₃ of relay E , the position shown in dotted lines applies. The relay E is namely energized via the normally closed contact b _{± of} the relay B when the apparatus is idle. Through the contact device 11, the heating circuit is the

Input tube closed again intermittently. If one of the stations of the entire telephone system is to be called, voltage is applied to the long-distance line to which all stations are connected. In each station, as soon as the contact device 11 closes the next time, the relay A and the relay B are energized. The excitation of the relay B causes the opening of the RÜhekontakt b _x , the relay E drops out and closes its break contact e _± in the circle of the self-holding winding A '. The relay E also opens its normally open contact e ₂ and closes its normally closed contact _{e z} . While the opening of the contact e ₂ and the closing of the normally closed contact e _{a is} initially irrelevant, the closing of the normally closed contact e _{± completes} the circuit for the self-holding winding Ä so that the relay A initially remains energized via this self-holding winding. Closing the normally open contact b ₂ causes the rotary magnet C for the selector 15 to be excited. This is set up so that the selector arm does not move when the rotary magnet armature is tightened, but that this movement only comes about when the rotary magnet is de-energized Anchor falls off again. This is the case at the end of the pre-pulse, i.e. at time t ₂ (Fig. 3b). At this point in time, the normally closed contact b _t is closed again and thus the relay E is energized again. The actuation of its contacts, that is to say the opening of the normally closed contact e _x and the closing of its _{normally open contact e 2} , however, only takes place after the delay time has elapsed. Before this has expired, the first selection pulse, which may last _{from time i 3} to i _{4, is transmitted on the long-distance line.} At time i ₃ , the normally closed contact b _{t is} opened and the _{normally open contact Zb 2 is} closed. When the contact b _t is opened, the relay E drops out again. By closing the contact Zb ₂ , the rotary magnet C of the selector 15 is excited, so that at the time i ₄ the selector arm is moved from the first to the second contact. At time i ₄ , contact b _t is closed again. Its closure causes a new excitation of the relay E. However, before its delay time has elapsed, a new selection pulse begins, so that contact ^ closed, e ₂ remains open. Assuming that selection pulses are transmitted on trunk line 4 in this way, the voter arm reaches contact 5 of the voter at time t _s. As a result, an excitation circuit for the relay D is formed, which responds with a certain small delay and closes its working contacts d _t and d _2. The normally open contact d _x is in the actuating circuit for the bell Ί4, in which there is also an interruption device 16. The bell 14 is accordingly actuated, to be precise in the cycle given by the interruption device 16. The closure of the normally open contact d ₂ creates a self-holding circuit for the relay D, in which, in addition to this contact, there is also a contact A ₁ , which is located on the cradle of the telephone set and is closed as long as the receiver rests and also the normally closed contact e _{3 of} the relay E.

If the receiver is lifted at the signal of the bell 14, the contact A _{1 is} opened, the relay D is de-energized by opening the contact Zi ₁ , and the bell signal disappears because the _{normally open contact ^ 1 of} the relay D also opens. _{Another contact A 2} is located on the cradle of the handset, which is connected in parallel to the contact device 11 and is closed as soon as the called station answers, ie at the same time as contact A _{1 is opened} . In addition, when the receiver is picked up, a contact h _{3 is also} closed, which causes the rotary magnet C to be returned to the position shown in Fig. 3a. This is done in such a way that a contact n attached to the grooved disc 17 of the selector 15, which is closed as long as the selector arm is not in the position shown, forms a circuit for the rotary magnet C , in which a circuit shown in Fig 3 a is not with the drawn contact that is actuated with each armature movement of the rotary magnet. Accordingly, the selector 15 immediately returns to its starting position when the handset is picked up. Whether the relay E runs through its entire stroke and the contact e _x and the contact e _s opens and the contact e ₂ closes, depends on whether the telephone currents during a time that is longer than the response delay of the relay E on a value which is below the response sensitivity of relay B will decrease. If this is the case, the self-holding circuit of relay A is interrupted, that of relay D would have already been opened by lifting the receiver at contact A ₁ . If this is not the case, relay A remains energized via its self-holding contact, and contact device 11 remains bridged by contact Ji _{2 for the duration of the conversation.} However, if the called station does not answer, the contacts A ₁ to Zi ₃ remain in the position shown in Fig. 3a. The bell only sounds until the response delay of relay E, which in contrast to the device according to Fig. I a

about a minute has passed. The normally closed contact e _u then opens so that relay A is de-energized, and the normally open contact e ₂ closes so that the selector 15 returns to its initial position in the manner described. The normally closed contact e _s is also opened, so that the self-holding circuit of the relay D is interrupted and the bell signal disappears.

If more or less than four pulses arrive after the distant signal, the voter arm comes to rest on one of the unoccupied contacts of the voter 15. The bell 14 is then not actuated, and after the delay time of the relay E to the normally open contact e ₂ is closed, so that the selector. "Position runs back in its start. The relay D is because of its response delay when passing the Kpntaktes 5 part of the voter arm not actuated.

The circuits shown in the figures are only exemplary consider. For example, it may be necessary in addition to the input tube 10 to switch on several amplifier tubes, especially if it is a high-frequency telephone station or one with loudspeaker reception. Furthermore, the transmitter is when the receiver is lifted to put the called station into operation. The involvement of these facilities, namely the switching on of the heating of the hot cathode tubes contained in them, is also conveniently controlled by contacts on the cradle of the telephone set are attached, or of a relay, the response of which is made dependent on whether the selection device accrued to a specific contact, which is assigned to the relevant station is.

The maximum time that can lie between the start of the call to the transmitting station, ie between the beginning of the distant signal and the beginning of the bell ringing of a receiving station, is apparently equal to the pause in the hot cathode heating. In order to keep this time as short as possible and still make the relationship between heating time and interruption time as favorable as possible, it is advisable to work with a short heating system and a correspondingly short break. For example, with the device described in Fig. 1 a, in which the heating is 1 second and the pause is 7 seconds, a device would be preferable in which the heating is only ¹ Z ₂ seconds and the pause is accordingly 3V ₂ seconds. Such a dimensioning can be carried out more easily when using hot cathode tubes with direct heating than when using hot cathode tubes with indirect heating. Furthermore, it is advisable to use tubes with red glow cathodes, since in tubes with pure tungsten filament the possibly occurring recrystallization in turn results in a shortening of the tube life and accordingly counteracts the purpose pursued by the invention.

Claims (8)

Patent claims: 1. Circuit arrangement for commissioning of amplifiers to be switched on in signal or telephone lines, whose input tube is not permanently in Heating circuit is, but only in case of need by a preparatory So Current surge 'is switched on continuously, characterized in that the hot cathode the input tube to its emission temperature in a regularly recurring sequence is brought and the preparatory current surge is so long that the hot cathode during its duration at least once their emission temperature is reached for the purpose of actuating switching means which ensure permanent closure the heating circuit for the duration of the signal or voice transmission. 2. Device according to claim 1, characterized in that a permanent working contact device (it) supplies the heating circuit with power intermittently. 3. Device according to claim 1 and 2, characterized in that the contact device (11) is a device influenced by the receiving device, during the duration of the signal or voice transmission and possibly during the duration of a selection call sign, closed contact ( O ₁ , Zz ₂ ) is parallel (Fig. Ι to 3). 4. Device according to claim 1 to 3, characterized in that a contact (e _t ) is provided whose actuation xio causes the opening of the contact (a _± , A ₂ ) lying parallel to the intermittently closed contact device after the signal or voice transmission has ended . 5. Device according to claim 1 to 4, characterized in that a self-holding relay (A) is provided after its response, which causes the bridging of the intermittently closed contact device (Fig. 1 and 3). 6. Device · according to claim ι to 5, characterized in that the switching changes necessary to cancel and restore the intermittently acting glow wire heating of contacts Qi ₁ , h ₂ ) on the fork of the telephone set, which are actuated when lifting the handset, is made dependent (Fig. 2 and 3). 7. Device according to claim 1 to 6, characterized in that the provision an election device and the further switching measures required to establish a connection, preferably the switching on of further hot cathodes, are effected in that either the handset of a telephone station is lifted or the dialing device runs on a specific contact assigned to the relevant station. 8. Device according to claim 1 to 7, characterized in that hot cathode tubes with direct heating, preferably those with a red-hot cathode will. 1 sheet of drawings