CS239528B1 - Circuit control for adjustable resistor control - Google Patents

Abstract

The circuit is intended for controlling variable resistors, which are used in various technological devices to provide long-term non-destructive memories of the analog type. The purpose is to improve the control of variable resistors so that the drive motor of the variable resistor block is always switched contactlessly to the maximum supply voltage. The purpose is achieved by connecting a circuit that consists of a control block, a comparator, two switching blocks, a power supply block and a variable resistor block.

Description

Controlled resistance control circuit wiring

The circuit is designed for control of adjustable resistors, which are used in various technological devices to ensure long-term non-destructive analog-type memories. The purpose is to improve the control of the controllable resistors so that the drive motor of the controllable resistor block is always contactless to the maximum supply voltage. The purpose is achieved by connecting a circuit consisting of a control block, a comparator, two switching blocks, a power block and a controllable resistance block.

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259 528

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BACKGROUND OF THE INVENTION 1. Field of the Invention

Adjustable resistors, formed as potentiometric motor-driven units, are used in various technological devices to provide long-term non-destructive analog-type memories. They are most often controlled by switching the driving motor by means of relay contacts. A DC motor controlled by DC amplifiers can also be used as a driving motor. Furthermore, a solution is known where the driving motor is a stepper motor. circuits.

The disadvantage of the first solution is especially limited switching speed and short contact life. · In case that a DC motor controlled by DC amplifiers is used to drive the adjustable resistor, the disadvantage of this solution is at low voltage levels where a large position error occurs. low voltage areas. The disadvantage of the stepper motor solution is the need to use special pulse sensors and complex evaluation circuits that are difficult to adjust and maintain.

These disadvantages are overcome by the wiring of the controllable resistance control circuit according to the invention.

The principle of the connection according to the invention is that the output of the control block is connected to the control input of the comparator, the first control output of which is connected to the control input of the first switching block and the second control output to the control input of the second switching block. The power input of the second switching block is then connected in parallel to the output of the power supply block and the power input of the first switching block when the output is connected to the first directional input of the controllable resistor block, the second directional input of which is output of the second switching block.

An advantage of the circuitry according to the invention is that the drive motor of the controllable resistor block is contactlessly switched to the maximum supply voltage, so that insensitivity does not occur with small changes in the control signal, and the service life and frequency is considerably higher.

The wiring of the controllable resistor is illustrated schematically by way of example in a block diagram in the accompanying drawing.

The controllable resistor control circuit according to the invention consists of a control block, such as a pushbutton switch, comparator 2, two switching blocks 2, 4, realized, for example, by a contactless switch, power supply block 6, which in this case is a 220 V / 24V transformer. The individual blocks 6 are then connected so that the output of the control block is connected to the control input and comparator 2, whose first control output e is connected to the control input b of the first switching block 4 and the second control output f to the control input c of the second switching block 2. The power input i of the second switching block 3 is connected in parallel to the output of the power block 6 and the power input d of the first switching block whose output is connected to the first directional input g of the resistor block 2.

The function of the controllable resistance control circuit according to the invention is as follows. The control input and comparator 2 receive a signal from the control block for controlling the position of the potentiometer, which is part of the adjustable resistance block 2. With respect to its polarity, the output signal from the comparator 2 is applied to the control input b of the first switching block 6 in the case of positive polarity and, in the case of negative polarity, to the control input c of the second switching block 2. It is part of the controllable resistor block 2, in one direction and the other of the control block 2 in the opposite direction, wherein the directional inputs h of the controllable resistor BL are always supplied with the maximum supply voltage from the supply block 6.

Claims (1)

SUBJECT OF THE INVENTION 239 528 Connection of a control resistor control circuit consisting of a control block, comparators, two switching blocks, a control resistor block and a power supply block, characterized in that the output of the control block is connected to the control input (a) of the comparator (2), e) is connected to the control input (b) of the first switching block (4) and the second control output (f) to the control input (c) of the second switching block (3), whose power input (i) is coupled to the power block output (6) and a power input (d) of the first switching block (4), the output of which is connected to the first directional input (g) of the resistor block (5), to the second directional input (h) of the second switching block (3) ) ·