SU1249489A1 - Device for checking parameters of operation of electromagnet - Google Patents

Abstract

The invention relates to instrumentation engineering and is intended for the control of electromagnets of direct current, which do not have their own contact groups. The aim of the invention is expansion. the functionality of the device- CTA by determining the speed of the return mechanism of the electromagnet. The device contains a power supply unit, a pulse generator, the first and second elements OR, the first and second triggers, and the first and second elements. The cops And, a current sensor, to the output of which an amplitude detector is connected via a key, a unit for changing the pulse period, the first, second, third and fourth switches and a series-connected differentiating element, a two-digit pulse counter, a standby multi-vibrator and a display element. The device provides a check of the current of the electromagnet operation, the establishment of the moment of reaching the speed limit of the return mechanism of the electromagnet and checking the stability of the electromagnet at the maximum speed. 1 hp ff, 4 ill. sl to 4 About “00 about

Description

one

The invention relates to instrumentation engineering and is intended to control DC electromagnets that do not have their own contact groups.

The aim of the invention is to expand the functionality of the device by determining the performance parameters of the return mechanism of the electromagnet.

Figure 1 shows the block diagram of the device; in fig. 2-4-diagrams of diagrams, which explain the principle of operation of the device.

The device contains a power supply unit 1, the first switch 2, the first element OR 3, the first 4 and second 5 input terminals, a current sensor 6, a differentiating amplifier 7, a limiter amplifier 8, the first 9 trigger, a bus 10 of resetting the device , amplitude detector 11, consisting of the third diode 12, capacitor 3, voltage follower 14, comparator 15 and shunt key 16, as well as key 17, second switch 18, pulse generator 19, first element I 20, block 21 following period changes pulses, fourth 22 and third 23 elements And, first 24 and second 25 pulse counters, bitwise comparison node 26, HE 27 element, second diode 28 third pulse counter 29, differential element 30, two-bit pulse counter 31, consisting of the first 32 and second (high) triggers 33 bits, the waiting multivibrator 34, the display element 35, the second element OR 36, the second element AND 37, the second trigger 38, the first diode 39, the third 40 and the fourth 41 switches.

The device works in a consistent manner. .

Before starting the test, a monitored object is connected to the input terminals 4 and 5 of the device (an electromagnet winding), and a short pulse is fed to bus 10 (Fig. 2a) to reset the device to its initial state. The falling edge of this pulse, the trigger 9, is set to one (fig.2d), and the signal from the output of this trigger closes the analog switch 17 by connecting the input of the detector 11 to the current sensor 6. In addition, for the duration of the pulse

five

The initial state closes the key 16, discharges the capacitor 13, sets the counter 29 to the zero state, sets the trigger 38 into the Sfg.Zh) state, and from its output the level of the logical unit goes to the second input of the And 20 element, preparing it opening. Having passed through the OR 36 element and the developing diode 39, the indicated pulse sets the counter 31 (fig.3m) and the counter 24 of the block 21 to the zero state, respectively. The power supply diode 28 in block 21 does not allow the impulse to reset the circuit to the input of the counter 25. The monitoring device provides for the operation of the circuit in three modes: the first mode of checking the magnet current of the electromagnet; The second mode is setting the moment of reaching the limit value of the response parameters (response speed j of the return mechanism of the electromagnet; emergency mode; test of the stability of the operation of the electromagnet with the limit values of the response parameters (speed) of its return mechanism i

In the first mode, when checking the magnitude of the current, the electromagnet is switched on the switch 18 (FIG. 2, time 42), and the voltage from the output of the power supply unit 1 through the OR element 3 goes to the device input terminal 4 and through the electromagnet winding (not shown) device input terminal 5 and current sensor 6. The current in the winding of the electromagnet increases according to a certain law (Fig.26). The voltage drop across the current sensor 6, proportional to the current, is differentiated in time by the differentiating amplifier 7 (Fig. 2BX Amplifier-limiter 8 isolates and amplifies a negative polarity pulse (Fig. 2d), at the falling front of which trigger 9 is set to the zero state ( figd), thereby opening the key 17 (figure 2, moment of time 43).

The capacitor 13 is charged to the amplitude value of the voltage corresponding to the current of the electromagnet (Fig. 2b, 1,). With a further increase in the current after the electromagnet triggers, the voltage on the capacitor 13 does not change,

0

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0

five

since the key 17 at time 43 (FIG. 2) opens, disabling the input of the detector I1. The constant voltage at the output of the repeater 14 (Fig. 2e) is proportional to the current of operation of the electromagnet, since

where Uflt ,, (- - output voltage

amplitude detector, corresponding to the maximum current on the site 42-43. (figure 2);

RC - sensor resistance,.

6 current.

In the second mode, to establish the moment of reaching and determining the limiting value of the response (speed) parameters of the return mechanism of the electromagnet, after setting the circuit to the initial state, all bits of the counter 25 of the block 21 are closed, then switches 2 and 40 are closed, and switch 18 is locked. P1 pulses from the output of the generator 19 (FIG. 3a) through element I 20 are fed to the input of block 21 and through element I 22 to the input of counter 24. After passing () pulses, all bits of counter 24 are set to one (T1 is NUMBER of bits of counter 24 pulses). When the counter 24 is filled, the output of the node 26 establishes the level of the logical unit, which opens element 23 and element 22 closes, since at the input signal from the output of the amplifier-limiting amplifier 8 a pulse is removed (FIG. 3l), due to the presence of a falling section in the current of the electromagnet arising from the movement of the moving system of the electromagnet

ka 26 enters through the element NOT 27, the falling edge of the first pulse, pro-40 when it is activated. Impulse with released through the element. And, 23, the stroke of the amplifier of the limiter 8 is set to 24 in 24, through the decoupling diode 28, to the zero state, and the number written to the counter 25 decreases by one. As a result, 45 at the output of block 26 the logical zero level is again set, and from the output of block 21 a pulse is removed (Fig. 3i) with a duration equal to the pulse following period from the output of the generator 19. The circuit of block 21 is restored to its initial state and 22 is open, and element 23 is closed, while the number recorded in the counter 25 is reduced 55 control pulses from the output of the block to one. After passing through 21 above the limiting value of the para-element AND 22 () pulses of the number, meters of response (speed) recorded in the counters 24 and 25, the return mechanism, the electromagnetic element OR 36 enters the input of the installation of the counter 31 to the zero state and sets it to zero state. As a result, the logical level zero is maintained at the output of the high bit of the counter 31. In addition, the pulse from the output of block 21 is recorded in counter 29.

If the return mechanism of the electromagnet does not have time during the pause between the pulses that control the operation of the electromagnet, return to its original state, i.e., the frequency

- ten

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49489.4

chats equal, as a result of which the output of node 26 again sets the level of the logical unit and forms a second pulse at an interval of 5 equal to (2 -2) periods of the pulse generator. Further processes are repeated in the same way. In this case, the interval between the following pulses. will be for the period of the generator pulses less than the previous I1 of the shaft (fig. Zi). The spreading diode 39 does not transmit pulses to the zero state of the counter 24 on the bus 10 to set the device to its initial state during the formation of pulses from the output of the block 21.

On the leading edge of each pulse from the output of block 2I, differentiating element 30 produces short or short pulses (FIG. 3k), which arrive at the counting input of counter 31. At the same time, the pulse from the output of block 21 through the element OR 3 goes to input terminal 4, and pass

25 through the electromagnet winding to the input terminal 5 and current sensor 6.

If the return mechanism of the electromagnet works rhythmically, and its speed has not reached the limit

The 30 values of the triggering parameters or the triggering parameters of it at the present moment of time have reached the limit value, after each triggering of the electromagnet from the output

35 amplifier limiter 8 is removed pulse (Fig.3l), due to the presence of a falling section in the current of the electromagnet, resulting from the movement of the moving system of the electromagnet

20

40 at his time. The impulse from the output of the limiting amplifier 8 through 45 50 55 pulses from the output of the block 21 is higher than the limiting value of the response (speed) parameters of the return mechanism electromagnetically activated. The pulse from the output of the amplifier-limiter 8 through the control of the pulses from the output of the block 21 above the limit value of the response parameters of the return mechanism of the electromagnet element OR 36 enters the input of the installation of the counter 31 to the zero state and sets it to the zero state. - the output of the high bit of the counter 31 is the logic zero level. In addition, the pulse from the output of block 21 is recorded in counter 29.

If the return mechanism of the electromagnet does not have time during the pause between the pulses that control the operation of the electromagnet, return to its original state, i.e., the frequency

so, then the pulse to the input of the installation in the zero state of the counter 31 does not arrive (Fig, 3l, time 44). In this case, the counter 31 is not set to the zero state and the first discharge of the counter remains with the logical 1, which is recorded on the leading edge of the next pulse from the output of block 21 (Fig. 3k). Upon the arrival of the next pulse (fig.Zi, time 45), the output of the high bit of the counter 31 appears logical 1 (fig.3m), which enters the input element elem; nta I 37 and prepares it for opening, as well as the waiting multivibrator 34 is started (FIG. 3H). In this case, the next impulse from the output of the generator (fig. Ze, time 46) goes to the first input of the element I 37 and opens it. Passing through the element I 37, this impulse (FIG., Sn) I at the trailing edge sets the trigger 38 to the zero state (FIG. ZJ). As a consequence, the element And 20 is closed, thereby interrupting the arrival of pulses at the input of block 21 and the formation of pulses from the output of block 21. At the same time, counter 29 records the number of pulses generated by block 21 per cycle, checks, and the output pulse of the waiting multivibrator 34 ( fig.Sn). An indication element 35 is turned on, which notifies of the end of the cycle of checks to determine the limit value of the response parameters. (speed) of the return mechanism of the electromagnet. At the end of the test, it opens. switches 2 and 40.

The last impulse, from which the electromagnet has yet triggered, will be t-2, where 2 is the number of pulses recorded in counter 31, and m is the number of pulses recorded in counter 29. The speed limit of the return mechanism of the electromagnet will be determined by the duration of the pause between two previous pulses from the output of block 21, into which a certain number of pulses are output from the generator 19 with a predetermined follow-up period.

In the third mode, to check the stability of the electromagnet with the limiting values of the response parameters (speed) of its return mechanism, the switches 2 and 41 are closed, and the switches 18 and 40 become darker, the Generator 19 begins to form square impulses. (figr), which through the element OR arrive at the input terminal 4, and passed through the electromagnet winding to the input terminal 5 and the current sensor 6. The parameters of the generator pulses are chosen based on the conditions of maximum speed of the return mechanism of the electromagnet, i.e. during the time of action of the pulse, the working electromagnet has time to work, and during the time of the pause, it returns to its original state with a minimum return time.

. On the leading edge of each pulse of the generator 19, the differentiating element 30 forms short pulses (Fig. 4c), which are fed to the counting input of the counter 31.

If the electromagnet is fixed and works stably (without failures) at the maximum speed of its return mechanism, then after each pulse received at the counting input of counter 31, its input is set to the zero state from the output of amplifier-limiter 8 through the OR 36 element a pulse arrives ( fig.4t), due to the presence of a falling section in the current of an electromagnet, arising from the movement of a moving system of an electromagnet during its operation; As a consequence, at the output of the higher bit of the counter 31, a logical zero voltage is maintained.

When a failure occurs in the operation of the return mechanism of the electromagnet, the pulse does not arrive at the input of the installation to the zero state of the counter 31 (FIG. 4t, time point 47) :. In this case, the counter 31 is not set to the zero state and in the first discharge of the counter there remains a logical 1, which is recorded on the leading edge of the generator pulse (Fig. 4c). Upon the arrival of the next pulse from the output of the generator 19 to the counting input of the counter 31 (FIG. 4c, time instant 48) at the output of the most significant bit of the counter 3J. a logical 1 appears (fig 4u), with which the waiting multivibrator 34 is started (fig 4f). The output impulse of the waiting multivibrator includes an indication element 35, which notifies of the malfunctioning of the return mechanism of the controlled electromagnet.

When the electromagnet is triggered (fig. 4t, time 49), the counter 31 is again set to the zero state and after the end of the pulse of the waiting multivibrator 34, the circuit returns to the initial state and the test continues as described above. When the switches 2 and 41 are opened, the test ends.

Claims (2)

Invention Formula 1 A device for controlling the operation parameters of an electromagnet, containing a power supply unit connected by an output through a first switch to a control input of a pulse generator, and through a second switch to a first input of the first OR element connected by an output to the first input of a device, serially connected differential amplifier and limiting amplifier connected by the output to the first input of the second OR element, and to, the installation input to the zero state of the first trigger connected by the installation input to the unit the state with the second input of the second element OR, with the setup bus of the initial state of the device and with the control input of the amplitude detector connected by the information input to the first information key of the key connected by the control trigger with the first output of the first trigger, and the second information output with the second input of the device, the input of the differentiating amplifier and the first level of the current sensor connected by the second output to the common bus, the differentiating element connected by the output to the counting input of the two-channel a pulse counter connected by a setup input to the output of the second element OR, and a higher-order output to the input of a waiting multivibrator connected by an output to the input of the display element, characterized in that, in order to expand its functionality determining the speed parameters of the return mechanism of the electromagnet, the first and second elements AND, the second trigger, the third and fourth switches and the change unit — the pulse following period, connected to the input of the differentiating element and the second input of the first element OR, the information input with the output of the first element And, and the setup input to the initial state with the device setup bus in the initial state and the setpoint input to the single state of the second trigger connected to the direct output m to the first input of the first element And, and the input of the installation to the zero state to the output of the second element I-, connected by the first input with the output of the higher bit of the two-bit pulse counter, and the second input with the output of the first element And connected by the second an input to the first output of the third switch connected by the second output to the output of the pulse generator and to the first output of the fourth switch connected by the second output to the second input of the first OR element, 2. The device according to claim 1, which means that the unit for changing the period of the following pulses contains the third and fourth elements AND, the element NOT, the first and second diodes, the first, second and third counters pulses and a bit comparison node, connected by inputs to the outputs of the first and second pulse counters, and output to the output of the unit and the counting input of the third pulse counter, connected by the installation input to the installation input of the unit in the initial state and the anode of the first diode connected by the cathode to the installation th entrance first pulse counter and to the cathode of the second diode connected by an anode with the counting input of the second pulse counter and the output of the third element AND connected by the first input to the code of the bit comparison node and the input of the element NOT, and the second input to the information input of the block and the first input of the fourth element I, connected to the second input with the output element is NOT, and the output with the counting input of the first counter,