SU1213472A1 - Device for controlling reversible mechanism - Google Patents

Description

The invention relates to automation and is intended to control a reversing mechanism, for example, an executive electric motor, and its automatic reversal by means of contact switches when exposed to drive mechanisms t

The purpose of the invention is to improve the SA, its efficiency and increase its reliability.

The drawing shows a schematic diagram of the proposed device.

The circuit contains a reversible magnetic starter with contactors 1 and 2, the power contacts of the first of which (not shown) connect the stator windings of the motor to a three-phase network for rotation in the forward direction, and the second for rotation, in the reverse direction, triacs 3 and 4, through which windings of contactors 1 and 2 are connected to the network (terminals 5 and 6), control buttons 7 and 8 for switching the electric motor on and off, button 9 or 10, path switches 11 and 12, resistor 13 and alarm - contacts 14-17 contactors. The path switches used in the device are, for example, reed switches with switching contacts, which are permanently affected by a permanent magnet mounted on the tool.

The device works as follows.

When the supply voltage is applied, if the path switches 11 and 12 are in a certain state, both triacs 3 and 4 are locked, because no current flows to their control electrodes through open contacts 7, 8 and I 4 and 1 5. Pressing the button 7 closes the circuit composed by the contacts 9, the resistor 13, the path switch 11, the button 7, the triac control electrode-cathode 3, the contacts 16 and the contactor I winding, and the current flows through it, which causes unlocking of the triac 3 and operation contactor 1. At the same time, the pins 14 of the contactor are closed, the button 7 is shunt, and each half period opening (at the beginning of the half period) triac 3 shunts its control circuit, reducing the current flowing through, contacts 9, 11 and 14 to

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current pulses, the amplitude of which does not exceed the current unlock the triac.

An electric motor (not shown) begins to rotate in the forward direction. By closing the contacts 14, the contactor I is kept on, and the triac 3 is unlocked and after the button 7 is opened. At the same time, by opening the contact 17, the contactor 1 breaks the power supply circuit of the winding of the contactor 2, excluding the simultaneous activation of them.

When under the action of an actuator driven by an electric motor, the contacts of the directional switch 11 are switched, the control circuit of the triac 3 provides c, and the contactor 1 is turned off. Its power contacts 14 are opened, and contacts 17 are closed. Through the closure of the pins 11 of the control, the triac electrode 4 is connected, through the resistor 13 to its aiode, and the triac 4 is triggered, causing the contactor 2 to turn on. This contactor G uses its own power contacts: it turns the electric motor on the countershaft. At the same time, the contacts 15 of the contactor 2 are closed, and it is turned on in the switched on position and after switching the contacts of the contacts 11. At the same time the contacts 16 of the contactor 2 open, excluding the operation of the contactor I.

When the trip switch 12 is triggered, the control circuit of the triac 4 is de-energized, and the control electrode of the triac 3 is connected to the terminal 5 of the network, the triac 4 is closed and the contactor 2 is turned off, and its contact 16 is closed. Further on, the operation of the circuit is repeated.

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Thus, the proposed device for controlling the reversing mechanism by an electric motor is characterized by simplicity, high sensitivity and output power, the use of simple low-current track sensors on reed switches in it, as well as reliable operation when installing path switches in aggressive environments. Through the contacts included in the control circuit of the triacs, current pulses pass, the amplitude of which does not exceed the opening current.

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triacs, which dramatically increases the durability and reliability of industry and rural jobs in various industries. The proposed device can be sold.

Claims (1)

(57 Device for controlling the REVERSE MECHANISM, containing two triacs, two contactors, the first winding of each of which is connected to the first terminal. AC networks, two directional switches and a resistor, disconnecting it from the fact that, in order to simplify I a * niya and improve reliability, the device contains connected in series disconnect contacts of the first and second directional switches and. make contacts' of control buttons with connected in parallel. they are made by the contactor contacts of the contactors connected to the control electrodes of the first and second triacs, respectively, which are connected to the first output of the resistor through the make-up contacts of the second and first direction switches, the second output of the resistor is connected to the anodes of the triacs, which are connected to the second terminal of the network, and the cathodes of the triacs are connected with the second terminals of the contactor windings.