KR100758469B1 - Apparatus for detecting loose contect of resist volume in cpc potention-meter - Google Patents

Abstract

The present invention compares the resistance value of a potentiometer with a direct current motor moving a photosensor and checks the resistance value of the potentiometer for outputting an error signal if the resistance of the potentiometer does not change when the direct current motor is driven. The present invention relates to a resistance volume contact failure detection device. The present invention relates to a potentiometer resistance volume contact failure detection device of a center position control device, comprising: an electric motor driving detection unit for detecting an output value of a DC motor and determining whether to drive the same; The potentiometer input storage unit for reading and temporarily storing the output value of the resistance and the resistance value by comparing the output value of the current potentiometer with the previous value stored in the potentiometer input storage unit while the motor is being driven as a result of the determination of the motor operation detection unit. The comparison determination unit for determining whether or not the value changes, and the result of the comparison determination unit, the setting range is different from the resistance value of the potentiometer An error detection unit outputs an error detection signal when a phase change occurs.

Center position control (CPC), potentiometer, resistance volume, DC motor, photosensor,

Description

Resistive volume contact failure detection device of CPC potentiometer {APPARATUS FOR DETECTING LOOSE CONTECT OF RESIST VOLUME IN CPC POTENTION-METER}

1 is a detailed configuration diagram of a CPC apparatus according to the present invention.

2 is a diagram illustrating a terminal internal connection connecting a PC potentiometer and a control device.

Figure 3 is a block diagram showing a CPC potentiometer resistance volume contact failure detection apparatus according to the present invention.

4 is a detailed circuit diagram of the apparatus shown in FIG.

5 is a timing diagram illustrating an error detection state of a CPC potentiometer contact failure detection device applied according to the present invention.

6 is a block diagram illustrating a control device of a PC potentiometer to which a contact failure detection apparatus according to the present invention is applied.

* Description of the symbols for the main parts of the drawings *

1: Motor operation detection unit 2: Potentiometer input storage unit

3: potentiometer signal comparison determination unit 4: error detection unit

11 motor output detection unit 12 voltage level recognition unit

13, 34: comparison unit 14: chattering prevention circuit unit

15: delay time set volume unit 16: signal conversion unit                 

17: De-flip-flop circuit part 18: DC motor digital output 1 part

19: DC motor digital output part 2 21: potentiometer noise reduction circuit part

22: potentiometer temporary memory circuit 1 part 23: potentiometer temporary memory circuit 1 part

31: potentiometer deviation value comparison circuit section 32: signal amplification circuit section

33: Potentiometer final output unit 35: Potentiometer deviation comparison value setting unit

41: end gate logic circuit 42: error detection lamp unit

43: error detection relay unit

The present invention relates to a center position control (CENTER) to control the steel sheet to the center position on the table, more specifically, the potentiometer for detecting the current position of the steel sheet for the center position control The present invention relates to a resistance volume contact failure detection device of a CPC potentiometer, which detects a case in which a resistance contact failure does not operate normally and reduces an error in the center position control.

In general, the center position control CPC device adjusts the degree of inclination or tilting of a strip, which is a rolled material, and passes the strip between the sensors combined with the emitter and the receiver. When this occurs, the equipment reads out the values of the receivers and shifts the rolls in the opposite direction of the pull by using the cylinder by the deviation of the pulled direction so that the strip is always positioned at the center position at the exit side.

At this time, in order to control the degree of deflection of the strip, a light receiver photo-sense is installed. The photoelectric sensor is moved in the width direction of the steel sheet, and a small DC motor is used to read the moving distance value from the motor moving the photo sensor. The device applied as a control signal is a potentiometer.

Figure 1 shows a part of the general CPC device, ㉮ is a DC motor, ㉯ is a coupling portion, ㉰ is a potentiometer for measuring the travel distance by the DC motor (㉮), ㉱ is a V-belt Is an intermediate terminal box for inputting and outputting a control signal, is a photosensor for receiving light irradiated from the bottom to the top, and is the strip.

The potentiometer (㉰) is composed of an internal resistance coil in a reduced form, and each time the photoelectric sensor (㉳) shifts left and right by rotating the DC motor (㉮), the resistance coil part is scratched at a predetermined pressure. It is to read the changed resistance value.

However, when the resistance coil part of the potentiometer is scratched or the self-resistive coil shell is deteriorated, the resistance value cannot be read consistently. There is a problem that the position control becomes unstable.

The present invention has been proposed to solve the above-described problems, and an object thereof is to compare a driving signal with a resistance value of a potentiometer when a direct current motor moving a photosensor in a CPC device is operated when the direct current motor is driven. It is to provide a resistance volume contact failure detection device of CPC potentiometer that outputs an error signal if the resistance value of the meter does not change.

In addition, another object of the present invention is the resistance volume of the PC potentiometer to maintain the center position control by forcing the CPC device to perform the center position control without detecting the current position of the strip when the error of the potentiometer is detected. It is to provide a contact failure detection device.

In order to achieve the above object, the present invention in the potentiometer resistance volume contact failure detection device of the center position control device,

A motor driving detection unit detecting an output value of the DC motor to determine whether to drive the motor;

A potentiometer input storage unit configured to read and temporarily store the potentiometer output value;

A determination unit determining whether the resistance value is changed by comparing the previous value stored in the potentiometer input memory unit with the output value of the current potentiometer when the motor is being driven;

As a result of the comparison determination unit, it is characterized in that it comprises an error detection unit for outputting an error detection signal when a change in the resistance value of the potentiometer more than the set range.

In the above, the motor operation detection unit includes an output detection unit for detecting an output signal of the DC motor, a chattering prevention circuit unit for preventing chattering in the output signal, an operation delay unit for delaying the output signal of the DC motor for a predetermined time, and It consists of a signal converter for converting the output signal of the direct current motor output from the operation delay unit into a signal indicating the motor drive.

The potentiometer input memory unit removes noise from the output signal of the potentiometer to obtain a high quality resistance signal, and two memories for temporarily storing the potentiometer's previous resistance and the current resistance. It consists of a circuit part.

In addition, the potentiometer value comparing unit converts two resistance values output from the signal amplifying circuit unit into an absolute value and a signal amplifying circuit unit amplifying a current resistance signal and a previous resistance signal respectively stored in the potentiometer input memory unit. The circuit section includes a potentiometer deviation value setting section that sets a comparison reference value of the potentiometer, and an error determining section that compares the difference between the current resistance value converted into the absolute value and the previous resistance value out of the reference range to determine an error. .

The error detection unit AND logic processes the motor driving signal output from the motor driving detection unit and the error determination signal of the potentiometer comparison unit to drive the motor and output an error signal when the resistance value deviation is out of the reference range. A gate circuit portion, a ramp portion driven by an error signal output from the AND gate circuit portion, and a relay output portion are formed.

Hereinafter, with reference to the accompanying drawings will be described in detail the configuration and operation of the apparatus according to the present invention.

Figure 3 is a block diagram showing a resistance volume contact failure detection device of the CPC potentiometer according to the present invention, largely the DC motor output detector (1), the potentiometer input detector (2), and the comparison determination unit ( 3) and an error detector (4). At this time, a drive signal of a DC motor connected to one shaft is applied to the DC motor output detector (1), and the potentiometer input detector (2) is applied. Is applied to the potentiometer resistor output.

At this time, the signal extraction is performed in the terminal connection shown in Fig. 2 in the lines A1 and A2 for applying the drive signal to the DC motor and in the output signal application lines B1 and B2 of the potentiometer. Withdraw.

That is, as shown in Fig. 6, the CPC apparatus performs circuit wiring so that the input signal of the DC motor is drawn out and the output signal of the potentiometer is drawn out. In FIG. 6, the block 10 to which the input drawing signal of the DC motor and the output drawing signal of the potentiometer are applied is a potentiometer resistance volume contact failure detection device according to the present invention.

In the above, the motor driving detection unit 1 is the motor output detection unit 11, voltage level recognition unit 12, comparison unit 13, chattering prevention circuit unit 14, delay time set volume unit 15, signal conversion A unit 16, a de-flip-flop circuit unit 17, a DC motor first digital output unit 17, and a DC motor second digital output unit 18 are constituted.

Referring to the operation of the motor operation detection unit 1, the motor output value is read from the DC motor terminal A1 of the CPC receiver drive and inputted to the motor output detection unit 11.

The DC motor signal is compared with the setting value of the voltage level recognition unit 12 in the comparing unit 13, and outputs a signal indicating the motor driving state when the predetermined reference level (for example, DC 12 volts) or more. do. The output signal of the comparison section 13 passes through the chattering prevention circuit section 14. Here, a delay time set volume section 15 is provided for setting the chattering delay time of the chattering prevention circuit section 14 to an appropriate value. That is, the chattering prevention circuit part 14 finally outputs the motor drive signal when the output signal of the comparator 13 is maintained for a predetermined time in order to prevent the noise state from being recognized as the driving state.

Then, the motor driving signal is passed through the chattering prevention circuit unit 15 and the signal conversion unit 16 in which the photocoupler is installed, and the final actual DC value of the DC motor is converted into a digital signal recognizable by the logic circuit.

When a digital signal indicating that the direct current motor is in operation is generated by the above-described serial processing, the signal is introduced into the de-flip-flop circuit section 17, and the direct current motor is stopped and then restarted and stopped again. Whenever the repetitive operation is performed, the de-flip-flop circuit 17 performs flip-flop processing to the first digital output unit 18 and the second digital output unit 19.

Then, the potentiometer input memory section 2 is composed of a noise removing circuit section 21, first and second temporary storage sections 22, 23, and functions as follows.

At the terminal B1 of the potentiometer drive of the PC receiver, the resistance value of the potentiometer is taken out and input to the potentiometer input storage unit 21.

The potentiometer input signal is first filtered by the noise canceling circuit 21 to introduce clear signals.

The potentiometer input signal from which the noise is removed is input to the first and second temporary memory circuits 22 and 23, respectively.

Here, the first and second temporary memory circuits 22 and 23 respectively correspond to the first and second output signals 18 and 19 outputted from the de-flip-flop circuit part 17 of the motor driving detection unit 1, respectively. Connected to each other, the signal is switched to the first output unit 18 and the second output unit 19 of the de-flip-flop circuit unit 17 each time the DC motor is operated / stopped. The temporary memory circuits 22 and 23 alternately receive signals and store the potentiometer output signals at different time zones.

This makes it possible to compare the signal value when the DC motor is stopped with the signal value when the DC motor is stopped at every operation, thereby determining whether the potentiometer is disconnected and detecting the instantaneous resistance volume contact failure. will be.

The comparison determination unit 3 includes a first comparison unit 31, a signal amplifier circuit unit 32, a final output unit 33, a second comparison unit 34, and a deviation comparison value setting unit 35. Each block acts as follows.

The first comparator 31 is configured to compare the deviation of the signal values output from the first and second temporary memory circuits 22 and 23 of the potentiometer input memory 2. Since the potentiometer output deviation values generated at the first comparator 31 at the time of stop and operation are very minute, they are amplified by the signal amplification circuit part 32 because there is a need to amplify the signal.

Then, after comparing the output deviation of the potentiometer, the logic unit to amplify and finally hold the deviation signal is the final output unit 33.                     

In order to compare the output deviation of the potentiometer outputted from the final output section 33, the reference value, which is a reference, is set in the potentiometer deviation comparison value setting section 35.

The comparison unit 34 compares the reference value with the output deviation of the potentiometer and determines whether the output deviation is greater than or equal to the reference range.

The comparator 34 outputs the error generation signal when the potentiometer output deviation is less than the set value of the potentiometer deviation comparison value setting unit 35.

Finally, the error detection unit 4 is composed of an AND gate logic circuit unit 41, an error detection lamp unit 42, and an error detection relay unit 43, and the AND gate logic circuit unit 41 is the comparison unit. When an error detection signal is generated at 34, a high level signal is output when the error signal and the output of the signal converter 16 of the motor output detector 1 are simultaneously satisfied. This is to handle the error occurrence signal of the potentiometer only when the DC motor is operating.

When the output signal of the AND gate logic 41 is generated, an error of the potentiometer is generated. The signal is installed in the field so as to be immediately recognized in the field by the signal and connected to the output of the AND gate logic 41. The lamp 42 is turned on, and the relay section 43 is operated so that this potentiometer error signal can be used for control by another external control device.

In this way, the relay unit 43 may be used for the existing CPC device or facility control, or may be used in conjunction with an interlock of another control facility.

Fig. 4 shows an embodiment of the apparatus according to the present invention described above, which is a detailed circuit configuration diagram operating as described above.

FIG. 5 is an operation timing diagram of an apparatus according to the present invention, in which each output record is connected to four channels on the horizontal axis to determine whether the configuration of error detection logic according to an actual driving situation is suitable for the current situation. The detection status graph is shown.

That is, the error monitoring channel 200, the output terminal of the error detection relay, the motor output monitoring channel 201 in which the output signal of the signal conversion unit 16 is displayed, and the first temporary memory circuit unit 22 of the potentiometer 22. The display is divided into a channel 202 connected to the output terminal and a channel 203 connected to the output terminal of the second temporary memory circuit 23 of the potentiometer.

In the vertical axis of the graph, reference numerals 100, 101, and 102 denote operating sections of the DC motor.

Here, in the first section 100 and the second section 101, it can be seen from the channel 3 and the channel 4 that the output value of the potentiometer is normally changed as the motor repeatedly runs and stops.

However, in the third section 102, it can be seen from the channels 3, 4 (202, 203) that the motor is operating normally but the output value of the potentiometer is held unchanged.

The reason is that there is no signal change due to the contact resistance of the internal resistance volume of the potentiometer or the disconnection, etc. The DC motor is being operated while the potentiometer is operated for the same reason as above. You can't recognize it.

Therefore, at this time, as shown in the channel 1 (200), the relay and the lamp operates.

The use of the error detection relay 43 may be used, for example, in a PCC control device, so that the PC may be configured to be forcibly moved to a center position by a signal of the relay 43 when the potentiometer is defectively detected. Can be.

Therefore, in the present invention, the center position control of the CPC is used to move the light receiver sense using a DC motor, the CPC which reads the DC motor movement signal with a potentiometer which is an annular resistor composed of a series of axes It is used in equipment.

 When DC motor is shifting to detect the center position, the potentiometer internally monitors the contact resistance of the annular resistance part of the potentiometer, so that a resistance contact failure occurs or the potentiometer input of the internal resistance coil is disconnected. In this case, the detection of this situation is recognized by the logic of the CPC potentiometer resistance volume contact failure detection device of the present invention so that the equipment is always operated at the CPC center position by using the detected error detection signal.

The present invention, which operates as described above, has the advantage of enabling precision control and error monitoring of the CPC by using the resistance volume detection error detection signal for CPC error control of an existing facility or by interworking with other sector interlocks.

Claims (5)

In the potentiometer resistance volume contact failure detection device of the center position control device, A motor driving detection unit detecting an output value of the DC motor to determine whether to drive the motor; A potentiometer input storage unit configured to read and temporarily store the potentiometer output value; A determination unit determining whether the resistance value is changed by comparing the previous value stored in the potentiometer input memory unit with the output value of the current potentiometer when the motor is being driven; The resistance volume contact failure detection device of the CC potentiometer, characterized in that it comprises an error detection unit for outputting an error detection signal when a change in the resistance value of the potentiometer as a result of the comparison determination unit. The method of claim 1, wherein the motor operation detector An output detector for detecting an output signal of the DC motor, A chattering prevention circuit section for preventing chattering in an output signal; An operation delay unit for delaying the output signal of the DC motor for a predetermined time; And a signal conversion unit for converting an output signal of the DC motor output from the operation delay unit into a signal indicating the driving of the motor. The method of claim 1, wherein the potentiometer input memory unit A noise filter circuit unit for removing noise from the output signal of the potentiometer to obtain a high quality resistance signal; And a resistance volume contact failure detection device of a CPC potentiometer, characterized in that the first and second temporary memory circuit units alternately temporarily store an output signal of the potentiometer input through the noise filter circuit unit. According to claim 1, wherein the potentiometer value comparison unit A signal amplifying circuit unit for amplifying an output signal during operation and an output signal at a previous stop stored in the potentiometer input memory unit, respectively; An absolute value converting circuit part for converting two resistance values outputted from the signal amplifying circuit part into an absolute value; A potentiometer deviation value setting section that sets a comparison reference value of the potentiometer, And an error determination unit for determining an error by comparing a difference between the current resistance value converted into the absolute value and the previous resistance value out of a reference range. The method of claim 1, wherein the error detection unit An AND gate circuit unit which performs an AND logic process on the motor driving signal output from the motor driving detection unit and the error determination signal of the potentiometer comparison unit to drive a DC motor and outputs an error signal when the resistance value deviation is out of a reference range; Resistive volume contact failure detection device of the CPC potentiometer, characterized in that consisting of a lamp unit and a relay driven by the error signal output from the AND gate circuit portion.

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