SU1675955A1 - Driving electromagnet control device - Google Patents

Description

The invention relates to devices for controlling drive electromagnets, mainly drive electromagnets of braking devices, and most effectively can be used in electric drives to lift conveyor machines.

The purpose of the invention is to increase functional reliability.

FIG. 1 is a block diagram of the device; in fig. 2 - graphs illustrating the operation of the device; where voltages and currents are represented on the corresponding elements.

The device consists of an adjustable power source 1, to the output of which the winding of the driving electromagnet 2 is connected, the meter 3 of the current connected to the motor core of the mechanism (not shown), the threshold element 4 and the differentiating unit 5 whose inputs are connected to the output of the meter 3 polarity, the input of which is connected to the output of the differentiating unit 5, and the output - to the input S of the mode switch 7 (RS-flip-flop), the time delay element 8, the output of which is connected to one of the inputs of the IL-9 element and to the input m R switch 7, element And 10, one of the inputs of which is connected to the output of the element OR 9, and the output - with one of the inputs of the element And 11, the second input of which is connected to the output of the threshold element 4, and the output with one of the inputs of source 1 whose second input is connected to the output of the switch 7 and to the input of the element NO 12, the output of which is connected to the second input of the element OR 9, the input of the element 8 and the second input of the element 10

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Connected to the control signal source y (not shown), the output of element 10 is connected to the power source (not shown) of the electric motor core.

FIG. 2a is a control signal (voltage at the inputs of elements 8 and 10); b - voltage at the output of element 8; c is the voltage at the output of element 10; g - change in current in the electric motor core circuit; - change of current differential in the electric motor core circuit; e is the change in voltage at the output of element 11; g is the change in voltage at the output of element 7; and - voltage variation at the output of power supply 1. The dashed lines show the graphs of changes in the parameters during failure of the disinhibition.

The device works as follows.

When the control signal Uy is applied, the outputs of the time delay elements 8, OR 9 and And 10 appear logical 1. Logical 1 from the output of element 8 sets the mode switch 7 to the initial state, logical 1 is set at its output, NOT 12 at the output of the element -logical O. Logic 1 at the output of element 10 permits the switching on of the engine power supply (not shown) and the supply voltage is applied to the electric motor. With an intact motor in the circuit of its core, a current appears (fig. 2d) and when it reaches the value determined by the threshold of element 4, a logical 1 is established at its output, which causes the appearance of logical 1 at the output of element 11 too. Regulated source 1, having two logical 1s at its inputs, applies the generated voltage (FIG. 2i) to the coil of the driving electromagnet 2, as a result of which the electromagnet’s measles moves, the motor disinters. The beginning of the movement of the motor core is accompanied by a decrease in the current in the core circuit to a value determined by the moment of resistance of the mechanism. When the core current decreases, a voltage appears at the output of the differentiating unit 5 (Fig. 2e) and through the polarity determiner 6 is fed to the input S of the switch 7, and logical O appears at its output. Under-action of this signal, the power supply source 1 reduces the voltage on the drive electromagnet to a value sufficient to hold the electromagnet core in the retracted position. At the output of the element NOT 12, a logical 1 is established at this time, which is fed to the input of the element OR 9, thereby eliminating further state changes at its output.

depending on the state of the time delay element 8. The switching off of the electric motor and electromagnet occurs when the control signal Uy is removed. If the release of the brake is incompetent (due to faults in the braking device, due to an open circuit of the coil of the electromagnet, etc.), the current in the motor circuit will not decrease, the current differential will be equal to 0

the output of the element 12 is preserved logical O and after a time, determined by the electromechanical constant mechanism, which the delay element is configured for, at the inputs and output of the element

9 a logical O is established, as a result of which the outputs of elements 10 and 11 are also set to logical O and with the electric motor core; and the supply voltages are removed from the coil of the electromagnet. The motor is braked. To bring the circuit to the initial state, it is necessary to disconnect the control signal source Uy.

Application of the proposed device

allows you to increase the functional reliability of the electromagnet control by eliminating the possibility of engine disinhibition with a faulty main circuit, eliminating prolonged

engine underflow, turning the braked shaft and destroying the brake linings after a failed brake brake.

Claims (1)

Formula of the invention A device for controlling a driving electromagnet containing an adjustable power source, a mode switch, a current meter, a differentiating unit, a polarity determining unit, a terminal for connecting a control signal source, two AND elements, an OR element, a delay element, and the mode switch is connected by its output To the control input of a regulated power supply supplying power to the winding of the driving electromagnet, the output of the current meter is connected to the input of a differentiating unit, the output of which is connected to the input of the polarity determining unit, the output for connecting the control source and one of the inputs of the first element And, different 5 by the fact that, in order to increase the functional reliability, a threshold element, an element NOT, an output for connecting the drive control unit of the drive, and the output of the delay element connected to one of the inputs of the mode switch, the other input of which is connected to the output of the polarity determiner, and with one of the inputs of the OR element, the other input of which is NOT connected to the output of the mode switch through the element, the output of the OR element is connected to another input of the first element and, the output of the first AND element is connected to one of inputs of the second element And, another input is connected to the output of the threshold element and with a terminal for connecting the drive motor control unit, the output of the second element I is connected to the second input of the regulated power source, the input of the threshold element is connected to the output of the current meter included in the drive motor core circuit. Exercise Digo / Gel i- / y -1 T. Scht Koryu engine 1