SU892720A1 - Timer - Google Patents

Description

(54) RBLV TIME

one

The invention relates to a pulse technique and can be used in electronic switching devices and automation to obtain a given time delay.

Known time relay, containing the time setting. RC circuit, reference voltage divider and comparing device made in the form of a transistor analogue of a four-layer pnp switch, a source follower, the output and input of which are connected to the input and output, respectively, the time of the master RC circuit, and between the outputs the divider of the reference voltage and the source follower is turned on by comparing the device 111.

The disadvantage of this relay is low reliability. During operation, the relay contacts are closed and the discharge current of the capacitor flows through them, which causes the contacts to burn. Besides TorojCxeMa, the time relay is complex and contains many radio elements. For example, only electromagnetic relays - two.

It is known a time relay containing an RC driving circuit, the output of which is connected to the input of a comparison device on a field and bipolar transistors, while the output of the comparison device is connected to the input of an output device, an additional field-effect transistor The dimmer is applied to the resistor, and the gate is connected via an additional resistor to another terminal of 10 m in the setting resistor 2.

However, the relay has a low reliability. During operation, the relay contacts close and the discharge current of the capacitor flows through them, which causes the contacts to burn. Also when switching; contact systems of electromagnetic relays, vibrating fenders arise, and a place like a contact of pressure, tax, and contact contacts. The contact bounce causes more intense burning of contacts, and is also accompanied by 2S shortwave parasitic radiation, i.e. creating radio interference. In addition, the time relay circuit is complex.

The goal of 113 acquisitions1) is to increase trustworthiness.

To achieve this goal, the time relay contains the first field-effect transistor, the channel of which is connected in series with the time setting resistor and the parametric voltage regulator input, and the gate through the resistor is connected to the OTHER output time of the setting resistor, the time setting capacitor is one face of which is connected with the gate of the second field-effect transistor, the first bipolar transistor, the collector of which is connected via a resistor to the power supply bus, the base with the source of the second field-effect transistor, A second bipolar transistor connected in a circuit with a common emitter, connected by a base to the input terminal, a collector to the emitter of the first bipolar transistor, the collector of which is connected to the output terminal. At that, the drain of the second field-effect transistor is connected to the output of a parametric voltage regulator, the second plate the time of the driving capacitor is connected to the collector of the second bipolar transistor and through a resistor to the power source bus.

The drawing shows the electrical circuit of the time relay.

The device contains the time specifying the KS circuit, consisting of the capacitor 1, the time of the setting resistor 2, the field-effect transistor 3, the channel of which is connected in series with the resistor 2, and the gate through the resistor 4 is connected to another output of the resistor 2, the field-effect transistor 5, the gate of which is connected with one of the terminals of capacitor 1 and field-effect transistor 3, another output of capacitor 1 is connected to the collector of the second bipolar transistor 6, and the field-effect transistor 5 is connected between the output of the parametric voltage regulator 7 and the base A bipolar transistor 8, the emitter of which is connected to the collector of the bipolar transistor 6, the collector of the first bipolar transistor being connected via a resistor to a plug power source and its base connected to the input terminal 9. The output terminal 10 and the output 11 of the parametric stabilizer tension

The time relay works as follows

In the initial state, the field-effect transistor 5 is open by the voltage supplied to its gate from the output 11 of the parametric voltage regulator 7 through the time setting resistor 2 and the channel of the field-effect transistor 3, and the current enters the base of the bipolar transistor 8. But the emitter of the bipolar transistor 8 is connected to the collector of the bipolar transistor 6, which

is closed, and since there is no control signal at its input, at the output terminal 10 of the time relay the voltage is almost equal to the voltage E cct The drive capacitor 1 is charged and the voltage across it is equal to the voltage difference between the power supply. and ECT voltage output 11 of parametric voltage regulator 7.

For normal operation, the time relay must be met

The power supply of this state of the time relay can be indefinitely long.

With the arrival of the control signal at the input terminal 9, the transistor b opens and the field-effect transistor 5 closes with the voltage present at the time of the master capacitor 1. Since the field-effect transistor 5 closes, the bipolar transistor 8 closes and, not looking at the fact that the bipole The transistor 6 is open by the control signal, the voltage at the output terminal 10 of the time relay does not change. At the same time, the discharge of the set capacitor 1 through the time set resistor 2 and the channel of the field-effect transistor 3 begins.

The discharge of the capacitor 1 occurs in a constant current, this mode is provided by the active resistance consisting of the resistors 2 and 4 of the field-effect transistor 3.

The voltage from resistor 2 is applied through resistor 4 & the gate of the field-effect transistor 3 by the blocking potential proportional to the current flowing through the resistor 2. The source-channel resistance is linearly dependent on the gate-source voltage. Thus, the capacitor 1 is discharged by a constant current. As soon as the capacitor discharges and the voltage across it becomes less than the cut-off voltage of the field-effect transistor 5, the field-effect transistor 5 opens, the transistor 8 also opens, and since the transistor 6 is open, the voltage at the output terminal 10 drops to almost zero. ,

After the control signal disappears at the time input and the transistor 6 closes, the device automatically returns to its initial state, and a voltage appears at the output terminal 10. Thus, a time delay is performed, the value of which depends on the parameters of the RC circuit.

Due to the fact that the emitter of the bipolar transistor 8 is connected to the collector of the bipolar transistor 6, and the collector of the latter is connected through a resistor to the power supply bus, the voltage on which is higher than the parametric output voltage

Claims (1)

Claim A time relay containing a first field-effect transistor, the channel of which is connected in series with a time-resisting * resistor and with the input of a parametric voltage regulator, and the gate through a resistor is connected to the other output of the time-setting resistor, a time-setting capacitor, one lining of which is connected to the gate of the second field-effect transistor, the first bipolar trans15 through a resistor with a power supply bus, a base with a source of a second field-effect transistor, characterized in that, in order to increase reliability, a second beep is introduced into it a polar transistor connected according to the scheme with a common emitter, _ connected to the base of the input terminal, a collector to the emitter of the first bipolar transistor, the collector of which is connected to the output terminal, while the drain of the second field-effect transistor is connected to the output of the parametric voltage regulator, the second lining of the timing capacitor is connected to a bipolar transistor collector and a resistor with a busbar source. secondly