SU1309093A1 - Control device for inductive load - Google Patents

Abstract

The invention relates to electrical engineering and can be used in pulsed switching of inductive loads, such as electromagnets of printing apparatus. The goal is to increase reliability by monitoring the control key and the inductive load. The device contains a generator 1, a control signal (US) from which opens the key 2. A current flows through inductive load 3, which, after removing the US through the optocoupler 7, enters the D input of the trigger 9 and, delayed by element 14, for the time of load current reduction arrives at the C-input trigger 9. Counter 12 records its passage. If there is no current through Zener diode 4 due to a key 2 failure or an interturn lock in winding 3, counter 10 remembers triggering of trigger 9. Display unit 15 operates if counter 10 dials a predetermined number of pulses, and counter 12 sends a reset pulse to counter 10, counting out a certain number of CSS, it changes the accuracy of the control, which allows the malfunction to be detected promptly. 1 il. 00 about CD О О 00

Description

The invention relates to electrical engineering and can be used in the case of multiple pulses of inductive loads, such as electromagnets of printing apparatus.

The goal is to increase reliability by monitoring the health of the control key and the inductive load.

The drawing shows the functional diagram of the device.

The device contains a generator 1 control pulses connected to the input of the transistor switch 2, the output of which is connected to one of the outputs of the inductive load 3, the second output of which is connected to the Zener diode 4, to the initial installation signal generating unit 5 and to the voltage source, and the second output the zener diode 4 is connected to a resistor 6, the second output of which is connected to the LED of the optocoupler 7, the second output of the LED is connected to the output of the transistor switch 2, and the photoreceiver of the optocoupler 7 is connected to the input of the threshold device 8, The output of which is connected to the D-input of the trigger 9, the output of which is connected to the counting input of the first counter 10, the reset input of which is connected to the output of the first element OR 11, the second input of which is connected to the output of the second counter 12, and the first input of the element 11 - to the reset input the counter 12, with the second input of the second element OR 13 and the output of the unit 5 of the initial installation, and the first input of the element 13 is connected to the counting input of the second counter 12, to the input of the delay element 14 and to the output of the generator 1, and the output of the delay element 14 is connected to C trigger trigger input 9, the R-input of which is connected to the output of the second element OR 13, in addition, the output of the counter 10 is connected to the display unit 15.

The control of the operation of the switch 2 and the inductive load 3 is based on the fixation of the current pulse arising from the self-induced EMF when the switch 2 switches to the cut-off area after removing the control signal.

The device works as follows.

When the power is turned on, the initial setup signal from block 5 enters the counter 12, through the OR 11 element — to the counter 10, and through the OR 13 element — to the R input of the trigger 9, sets them to the initial zero state. When a control signal is applied from the generator 1 to the input of the switch 2, a current begins to flow through the inductance 3, while the LED circuit of the optocoupler 7 is de-energized. After the control signal is removed, a current flows through the LED and, from the photodetector of the optocoupler 7, through the threshold device 8, the signal arrives at the D input of the trigger 9.

The falling edge of the control signal, delayed by element 14 for a time equal to the duration of the load current decrease, arrives at the C input of the flip-flop 9 and confirms the state of the flip-flop. Counter 10 does not change its state, counter 12 changes state by one, fixing

passing one control signal. If the current does not pass through the Zener diode 4 (due to the failure of the key 2 or this pulse has become shorter due to the inter-turn short circuit in the winding 3), the trigger 9 is switched by the delayed falling edge of the control signal. Counter 10 remembers one trigger trigger. The next control signal trigger 9 through the element OR 13 returns to its original state, the counter 12 counts each control signal. The display unit 15 is activated if the counter 10 dials a predetermined number of pulses. Counter 12

sends a reset pulse to the counter 10, counting a certain number of control signals.

Thus, the presence of the first counter eliminates an accidental indication of a malfunction, for example, in the event of a pulse of interference through the power supply network. And the presence of a second counter allows to vary the accuracy of the control. If, for 100 control signals (counter 12), there are, for example, four pulses with

trigger 9, the control accuracy is 96%; if you change the counting ratio of the counter 10 from four to two, the control accuracy is 98%.

The device allows you to quickly identify the malfunction. Operational control

reduces the level of information loss due to the operator’s fault, since the operator has the ability to timely detect faulty actuators of the information output device, which is how the invention is achieved.

Claims (1)

Invention Formula A device for controlling an inductive load, a circuit consisting of a Zener diode and a resistor connected in parallel with it, a transistor switch connected in series with the load, connected by an input to a pulse generator, and a threshold element, characterized in that and loads, additionally introduced a display unit, a setup block, a delay element, two counters, a D-flip-flop, two OR elements and an optocoupler, the LED of which is included in series with a lithron and a photodetector is connected to the D-flip-flop D-input through a threshold element, the C-input of which is connected to a pulse generator through a delay element, the R-input to the output of an OR element whose inputs are connected to a pulse generator and initial setup block, output D -trigger connected to the counting input of the first counter, the output of which is connected to the display unit. 1309093 34 and the reset input - with the output of the OR element, the counting input of which is connected to the gene-connected inputs to the unit with the initial pulse generator, and the reset input - from the installation and the output of the second meter, the initial installation unit.