SU1256192A1 - Electronic telegraph relay - Google Patents

Abstract

The invention relates to a pulsed electronic technology. It can be used in the output devices of data transmission equipment and telegraph equipment. The purpose of the invention: no increase in reliability. A device containing a bipolar transistor 1-4, a switching signal source 7, an inverter 8, information input 9, a load of 10 KS type, current sensor 11, Schmitt trigger 12, logic elements 13 and 14, diodes 15 are inserted into the device. -21, capacitor 22, third resistor 23. When overloaded (as well as with counter-inclusions), the device begins to work in the relaxation mode. At the same time, transistor switches 24-27 are closed most of the time and unlocked only for a short period of time, determined by the recharging time of the capacitor 22. The average current and power dissipation of transistor switches 24-27, even when overloaded, are relatively small, which increases the reliability of the device. 1 il. g (L

Description

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The invention relates to a pulsed electronic technology and can be used in the output devices of data transmission equipment and telegraph equipment.

The purpose of the invention is to increase reliability by transferring the device to the relaxation mode and additional protection of the switching transistors during overloads and on-line switching of telegraph devices.

The drawing shows a circuit diagram of the device ..

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The electronic telegraph relay contains the first 1, second 2, third 3, fourth 4 bipolar transistors, the bases of transistors 1 and 2 are connected respectively through the first 5 and second 6 resistors with the positive pole of the source 7 switched. signal, the emitters of transistors 3 and 4 are combined, the inverter 8, the input of which is connected to the information input 9, the load 10 RC-type. A current sensor 11, a trigger 12 UJMHTTa, the first 13, the second 14 logic elements AND, the first 15, the second 16, the third 17, the fourth 18, the fifth 19, the sixth 20, the seventh 21 diodes, the capacitor 22, the third resistor 23 are entered into the device. The first output of current sensor 11 is connected to the emitters of transistors 3 and 4 and to the anode of diode 15, the cathode of which is connected via a resistor 23 to the Jmitt trigger 12 and to the first output of a capacitor 22, the second output of which is connected to the second output of current sensor 11 and with a negative pole source 7 switched signal. The input of the inverter 8 is connected to the first input of an AND 13 logic element, and the output of the inverter 8 is connected to the first input of an AND 14 logic element, the second input of which is connected to the output of Schmitt trigger 12 and to the second input of a logical element And 13 and 14 are connected to the bases of transistors 4 and 3, respectively. The anodes of diodes 16 and 17 are connected to the positive pole of the source 7 of the switched signal, and the cathodes to the collectors of transistors 1 and 2, respectively; diode anode and 18, a cathode, koto -

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connected to the base of the transistor 1 and the anode of the diode 20, the emitter of the transistor 2 is connected to the second output terminal 10 and the anode of the diode 19, the cathode of which is connected to the base of the transistor 2 and the anode of the diode 21, the cathodes of the diodes 20 to 21 are connected respectively with collectors of transistors 3 and 4.

10 The switching part of the device contains four transistor switches 24-27, connected by a bridge circuit, in one diagonal of which the switching signal source 7 is switched, 15 and in the FRIEND 5TO - the load 10.

 The device works as follows.

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In the rated current mode, the voltage drop across the current sensor 11 does not reach the trigger threshold of Schmitt trigger 12, and a high potential is detected at the trigger output that allows switching of logic elements And 13 and l4. When a high potential (logical 1) arrives at information input 9, the signal from the logical output element And 13 unlocks transistor switches 24 and 27, and transistor switches 25 and 26 remain closed. In this state, the positive pole of the source 7 is connected to the first load terminal 10, and the negative pole of the source 7 is connected to the second load terminal 10. If a low potential (logical O) is applied to the information input 9, the transistor switches 24 and 27 are locked and the signal , coming through the inverter 8 and the logical element And 14, unlocks the transistor switches 25 and 26, which connect the positive pole of the source 7 with the second output of the load 10, and the negative. with the first output of this load.

In the event of an overload, the switched current increases sharply, the voltage on the current sensor 11 increases, and as the capacitor 22 is charged, the voltage at the Schmitt trigger 12 rises. As soon as this voltage reaches the trigger threshold, trigger 12 switches, its output potential decreases, prohibiting bridging logic gates And 13 and 14. As a result, all transistor switches 24-27 are locked and the current in load 10 ceases.

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At the same time, the voltage drop across the current sensor 11 decreases, the diode 15 closes and the capacitor 22 begins to discharge through the Schmitt trigger 12 input circuit. As a result, the trigger returns to its original state, allowing switching the logical elements AND 13 and 14. At the same time, the two transistor switches 24 and 27 or 25 and 26 are closed, providing a current in the load 10. If the overload persists, the Schmitt trigger 12, switches again and the process repeats.

Thus, when overloaded (as well as with counter-inclusions) the device begins to work in a relaxation mode. In this case, the transistor switches 24-27 are closed most of the time and unlocked only for a short period of time, determined by the recharging time of the capacitor 22 through the low-impedance input resistance of Schmitt trigger 12. The average current and power dissipation of the transistor switches 24-27, even when overloaded, are relatively small, which increases the reliability of the device. In turn, diodes 16-21 prevent electrical breakdown of transistors i-4 with counter-inclusions in the source line 7.

Putting the device into a relaxation mode of operation and an additional diode protection of the switching transistors during overloads and on-line switching of telegraph devices increases the reliability of the electronic telegraph relay.

Claims (1)

Invention Formula An electronic telegraph relay containing four bipolar transistors, the bases of the first and second transistors are connected respectively via the first and second resistors to Editor I. Shulla Compiled by A.Sidorov Tehred A. Kravchuk Order 4836/57 Circulation 816 Subscription VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Production and printing company, Uzhgorod, st. Project, 4 561924 the positive pole of the source com-. the mutated signal, the emitters of the third and fourth transistors are combined, the inverter, whose input is connected to the information input, a load, characterized in that, in order to increase reliability, a current sensor, a Schmitt trigger, two logical elements And, seven diodes 0 capacitor, the third resistor, the first output of the current sensor is connected to the emitters of the third and fourth transistors and the anode of the first diode, the cathode of which is through the third resistor 5 is connected to the Schmitt trigger input and the first capacitor terminal, the second pin of which is connected to the second current sensor pin and to the negative pole of the source of the switched signal, the inverter input is connected to the first input of the first log-. And the inverter output - with the first input of the second logical element And, the second input of which is connected to the output of the Schmitt trigger and with the second input of the first logical element And, the outputs of the first and second logical elements And connected to the bases 0 of the fourth and third transistors, the anodes of the second and third diodes are connected to the positive pole of the source of the switched signal, and the cathodes are respectively with collectors the first and second transistors, the emitter of the first transistor connected to the first output of the load and the anode of the fourth diode, the cathode of which is connected to the base of the first transistor Q and with the anode of the sixth diode, the emitter of the second transistor is connected to the second output terminal and the anode of the fifth diode, the cathode of which is connected to the base of the second transistor and the anode of the seventh diode, connected to the collectors of the third and fourth transistors, respectively. Proofreader M. Pojo