SU928655A2 - T flip-flop - Google Patents

Description

(5) TRIGGER WITH COUNTABLE INPUT

one

The invention relates to a pulse technique and can be used in all parts of the national economy in telecontrol and control systems, as well as in computing technology. .

According to the main auth. N 520710 is a trigger with a counting input, consisting of electromagnetic relays with switching and control groups of contacts, a capacitor, a discharge and a limiting resistor l.

The known trigger with a counting input does not have a sufficient degree of reliability of converting clock single-pole pulses from one input to two different-valued outputs, because at the time of closing and opening the control and switching contact of the relay, a self-induction inductive and capacitive load occurs between the relay coil and capacitor, due to the presence of combined power circuits. These unsteady transients destroy the relay contacts and significantly affect the duration of the input and output pulses. This is especially true when changing the duration of control pulses that do not coincide with the rate of discharge and charge time of the capacitor.

The purpose of the invention is to increase the reliability of converting control clock pulses from one input to two outputs.

To achieve the goal of a trigger with a counting input, containing two electromagnetic relays with switching and control groups of contacts, a capacitor and a discharge and limiting resistor, the moving contact of the switching contact group is connected to the power bus, the moving contact of the control contact group is connected through a common capacitor bus, which is connected to one output winding of the relay and one output once. , 39 random resistor, the other output of which is connected to the switching contacts of the switching and control groups, contacts, the closing contact of the switching group of contacts through the limiting resistor is connected to the closing contact of the control group and through the auxiliary relay coil with the second output of the relay, two diode keys are inserted -, the first output of one of which is connected to the limiting resistor, the middle point - with the closing contact of the control group, and the second output - with the output winding of the additional relay, second key included iody-parallel relay windings. To ensure a constant discharge time of a capacitor, its capacitance is subject to the condition of aperiodic discharge RW, where R is the resistance of the winding of the relay (taking into account losses in the magnetic system); L - relay inductance. The limiting resistor limits the amplitude of the second control pulse and its resistance is determined by the value of the constant charging time of the capacitor. R. s with where T is the time constant of the circuit in a row, T is the duration of the controlling Impulse, C is the capacitance of the capacitor. In the drawing, an image is shown in principle on a trigger circuit with a counting input. A trigger with a counting input contains electromagnetic relays 1, a switching group of 2 contacts and a control group of 3 contacts, a capacitor A, a discharge resistor 5 and a limiting resistor 6. The trigger again The two-diode key 7, the input connected to the limiting resistor 6, and the output with the start of the relay 1 and the midpoint through the moving contact of the control group 3 with the capacitor i, and the other two diode key 8, with the shunt winding of the relay 1, are output. Trigg p works as follows. The control pulse enters the trigger input, and the capacitor 4 is charged through the closed contacts of the switching group 2 and the control group 3. At the end of the control pulse, the moving contact of the control group 3 closes the discharge circuit of the capacitor 4 through the middle output of the diode key 7 at the beginning of the relay coil 1. Under the action of the aperiodic discharge current of the capacitor k, the relay 1 pulls its core and the movable contact of the switching group 2 closes the circuit to the resistor 6. The switched on diode in the switch 7 prevents the falling of the discharge current into the control circuit. The discharge of capacitor k on relay 1 continues until the second control pulse arrives at the input of the trigger and then through the contact of the switching group 2, the limiting resistor 6 to the input of the switch 7 and from the middle point of the switch 7 through the closed contact of the control group 3 to the capacitor k, The discharged capacitor C shunts the windings of the relay 1. In the windings of relay 1, a self-induced EMF occurs and the induced current in the windings of relay 1 is closed along a separate circuit, created by the bridged leads of the key 8 and self-induction connected to the EMF and key 7. These keys separate the shunt charge of the capacitor k and the current circuit of the EMF self-induction windings of the relay 1, which, having sustained a slowdown to the cost of the shunt action of the key 8, release their core and open the moving switches and control contacts of groups 2 and 3 to the starting position. The capacitor 4 is discharged to the resistor 5 during the interval. With the arrival of the third control pulse, the trigger works in a similar way. The presence of separate capacitive and inductive load circuits eliminates the occurrence of unsteady transients between them and increases the service life of the relay contacts. The use of EMF of self-induction windings for self-deceleration of both relays by one separate

Claims (1)

Claim Trigger with counting input No. 5207U, characterized in that, in order to increase the reliability and durability of the trigger, two two-diode keys are inserted into it, the first output of one of which is connected to the limiting resistor, the middle point - with the closing contact of the control group, and the second "output - with the output of the winding additional relay, the diodes of the second switch are turned on in parallel to the relay windings.