KR19980076031A - Apparatus and method for detecting abnormality of feedback signal line of servo motor encoder - Google Patents

Abstract

The error detection device of the feedback signal line of the servo motor encoder is to check the open / short of the feedback signal line of the open collector servo motor encoder, and the open collector equipped with the servo motor In the servo motor encoder of the Collector type, detecting the rotation order of the feedback signal generated by the encoder and detecting the rotation direction of the servo motor, and outputting an up / down pulse according to the detected result; Up / down counting up / down pulses, reading up / down counted up / down pulse data and feedback signals of the encoder to search for abnormality of a feedback signal line, and generating a beep according to the search result. The gist is that it consists of a corresponding device.

Description

Apparatus and method for detecting abnormality of feedback signal line of servo motor encoder

The present invention relates to a servo motor encoder, and more particularly, to an apparatus and method for detecting an abnormality of a feedback signal line of a servo motor encoder of an open collector system.

Hereinafter, a feedback signal line abnormality detection device of a line drive servo motor encoder according to the related art will be described with reference to the accompanying drawings.

Fig. 1 is a block diagram showing an apparatus for detecting a feedback signal line abnormality of a line drive servo motor encoder according to the prior art. The configuration includes a servo motor 1 driven in accordance with an input drive signal. The encoder 2 which encodes the rotational amount of the servo motor 1 and generates a feedback signal according thereto, and detects the rotation direction of the servo motor 1 by searching the input order of the generated feedback signal. A pulse generator 3 for generating an up / down pulse according to a detection result, a counter 4 for counting up / down the generated up / down pulses, and the encoder 2 A signal line searching unit 5 for logically calculating the generated feedback signal and searching for an abnormality of the signal line according to the logic operation result, and storing the signal output from the signal line searching unit 5 and controlling the corresponding signal. signal It has been composed of a control unit 6 for outputting.

The signal line search unit 5 connects the first to third exclude or gates IC-1 to IC-3 to the output terminals of the encoder 2, respectively, and the first to third exclude. The fourth exclusive OR gates IC-4 are connected to the OR gates IC-1 to IC-3, respectively.

The operation of the apparatus for detecting the presence or absence of a feedback signal line of a servo motor encoder of a line drive method according to the related art configured as described above will be described.

First, when a user drives the servo motor 1 using a keypad (not shown), the controller 6 outputs a control signal corresponding to the signal input from the keypad.

Then, the servo motor driver (not shown) drives the servo motor 1 according to the output control signal.

In addition, the encoder 2 encodes the amount of rotation caused by the driving of the servo motor 1 and thus is a feedback signal. , Prize, , Phase and, , Generate phase.

Here, the feedback signal generated , The phase indicates that the servo motor 1 is driven clockwise as an up count signal, , Phase (each , Phase and 90 ° phase difference) indicate that it is driven counterclockwise as a down count signal, , The phase represents the output of one pulse per revolution of the servo motor 1.

The encoder (2) is a line drive type encoder, which is generated by supplying 10V to a driving power source. , , Each phase is 5V, , , The phases are -5V each.

Accordingly, the pulse generator 3 is the generated feedback signal Prize, The rotation order of the servo motor 1 is detected by searching the input order of the phases, and an up / down pulse corresponding to the detection result is output.

remind , The phase is not used in the pulse generator 3.

The counter 4 then counts the output up / down count pulses and stores the up / down count data in an internal memory (not shown).

Meanwhile, the signal line search unit 5 is a signal fed back from the encoder 2. , Prize, , Phase and, , Logical operation of the phase is performed to search for abnormalities in the signal line according to the result of the logical operation.

That is, if the first to third exclusive or gates IC-1 to IC-3 of the signal line search unit 5 have no abnormality in the feedback signal line of the encoder 2, the feedback is performed. , Prize, , Phase and, , The high signal is output by performing logical OR of each phase.

The high signal output from each of the first to third exclusive or gates IC-1 to IC-3 may include a power supply Vcc input from the fourth exclusive or gate IC-4; Exclusive-OR is output as a low signal.

According to the output low signal, the controller 6 determines that the signal line of the encoder 2 is not open / short.

On the other hand, if there is an error in the search result feedback signal line, for example , If the upper signal line is open / disconnected, the first exclusive or gate IC-1 outputs a low signal.

In addition, the second and third exclusive or gates IC-1 and IC-2 output high signals as described above.

Therefore, a low signal output from the first exclusive or gate IC-1 and a high output from the second and third exclusive or gates IC-1 and IC-2. The signal is OR-excluded with the power supply Vcc input from the fourth exclusive or gate IC-4 and output as a high signal.

According to the output high signal, the controller 6 determines that the signal line of the encoder 2 is open / shorted.

However, the feedback signal line abnormality detecting device of the line drive servo motor encoder according to the related art uses a line drive type encoder, so a gate is added to detect an abnormality of the feedback signal line of the encoder. As a result, there is a problem that the manufacturing cost increases.

In addition, when using an open collector servo motor encoder, an inverted signal among feedback signals ( Prize, Phase and, Since the phase is connected to the ground of the encoder, there is a problem in that an abnormality of the feedback signal line cannot be detected.

Accordingly, the present invention has been made to solve the above problems, the feedback signal line of the servo motor encoder for checking the open / short of the feedback signal line of the open collector servo motor encoder. Its purpose is to provide an abnormality detection device.

Another object of the present invention is to provide a method corresponding to a feedback signal line abnormality detection device of a servo motor encoder for achieving the above object.

1 is a block diagram showing an apparatus for detecting a feedback signal line abnormality in a line drive servo motor encoder according to the related art.

2 is a block diagram showing an embodiment of an apparatus for detecting an abnormality of a feedback signal line of an open collector servo motor encoder according to the present invention.

FIG. 3 is a flowchart showing an operating state of the controller of FIG. 2.

Explanation of symbols for the main parts of the drawings

101: servo motor 102: encoder

103: pulse generator 104: counter

105: control unit

In order to achieve the above object, a feature of the apparatus for detecting an abnormality of a feedback signal line of a servo motor encoder according to the present invention is an open collector type servo motor encoder having a servo motor, which is generated by the encoder. A pulse generator for detecting a rotation direction of the servo motor by searching an input order of a feedback signal and generating an up / down pulse according to the detection result, a counter for up / down counting the generated up / down pulse, And a control unit which reads the up / down counted up / down pulse data and the feedback signal of the encoder to search for an abnormality of the feedback signal line of the encoder and generates an alarm sound according to the search result.

In order to achieve the above object, the present invention provides a method for detecting an abnormality of a feedback signal line of a servo motor encoder, in an open collector servo motor encoder having a servo motor. Searching the input order of a feedback signal to detect a rotation direction of the servo motor and outputting an up / down pulse according to the detection result, up / down counting the output up / down pulse, and counting the up / down count Reading out the up / down pulse data and the feedback signal of the encoder and searching for an abnormality of the feedback signal line and generating an alarm sound according to the search result.

Hereinafter, a feedback signal line abnormality detecting device of a servo motor encoder according to the present invention will be described with reference to the accompanying drawings.

FIG. 2 is a block diagram showing an embodiment of an apparatus for detecting an abnormality of a feedback signal line of an open collector servo motor encoder according to an embodiment of the present invention. The configuration is a servo motor driven according to an input drive signal. A rotation direction of the servo motor 101 by retrieving the input sequence of the encoder 101 and the encoder 102 for encoding the rotational amount of the servo motor 101 and generating a feedback signal according to the input signal; And a pulse generator 103 for outputting an up / down pulse according to the detection result, a counter 104 for counting up / down the output up / down pulse, and the up The control unit 105 reads down / down counted up / down pulse data and the feedback signal of the encoder 102 to search for an abnormality of the feedback signal line of the encoder 102 and generates an alarm sound according to the search result. There is off.

The operation of the apparatus for detecting the presence or absence of a feedback signal line of the servo motor encoder according to the present invention configured as described above will be described.

First, when a user drives the servo motor 101 by using a keypad (not shown), the controller 105 outputs a control signal corresponding to a signal input from the keypad.

Then, the servo motor driver (not shown) drives the servo motor 101 according to the output control signal.

In addition, the encoder 102 encodes the amount of rotation caused by the driving of the servo motor 101 and thus is a feedback signal. Prize, Phase and, Generate phase.

Here, the feedback signal Prize, Phases are each 1000 pulses per revolution of the servo motor 101, Phase is 1 pulse.

Here, the feedback signal generated The phase indicates that the servo motor 101 is driven clockwise as an up count signal, Phase (each Phase and 90 [deg.] Phase difference indicate that it is driven counterclockwise as a down count signal.

The encoder 102 is an open collector type encoder, and is generated by supplying 12V to a driving power source. , , Phase is connected to internal ground Prize, Phase and, Sangwa , , The voltage difference of the phases is + 12V, respectively.

Accordingly, the pulse generator 103 is the generated feedback signal Prize, Multiply the phase by four Prize, The edges of the phases are searched to determine the input order and output corresponding Up / Down pulses.

The multiplication of the above is to improve the accuracy, and the output range of the up / down pulse value output is 0 to 3995.

Above search results disparity If you come in before the statue, At the rising edge If the difference is LOW, the pulse generator 103 determines that the servo motor 101 is rotating clockwise.

In addition, the above disparity If you come in before the statue, At the rising edge If the difference is high, the pulse generator 103 determines that the servo motor 101 is rotated counterclockwise.

Then, the counter 104 counts the output up / down count pulses and stores the up / down count data in an internal memory (not shown).

In addition, the counter 104 counts the current count value when the servo motor 101 is rotated once by an external influence such as manual operation by the user when no power is input, and stores the current count value in the internal memory.

Accordingly, the controller 105 reads up / down count data counted by the counter 104 through a data bus and stores the up / down count data in an internal register (not shown).

Each time the interrupt is taken, the controller 105 reads the read. Prize, Up / down count data on the generated or On the basis of the award Detects abnormality of phase feedback signal line Prize, An abnormality of the phase feedback signal line is detected and a warning sound is generated according to the detection result.

After that, the control unit 105 is supplied with power. Prize, Phase or An interrupt for searching for an abnormal signal line is repeatedly performed every predetermined time.

According to the above interrupt Prize, Up / down count data on the generated or On the basis of the award Detects abnormality of phase feedback signal line Prize, With reference to the flow chart showing the operation state of the control unit of the servo motor encoder of Figure 3 attached to the process of detecting the abnormality of the phase feedback signal line will be described in detail.

First, the controller 105 Prize, Up / down count data on the generated or On the basis of the award Detects abnormality of phase feedback signal line Prize, In order to detect the abnormality of the phase feedback signal line, an interrupt is generated during power supply.

Subsequently, if the servo motor 101 has rotated once, the controller 105 sets the first variable Z_Pulse in the encoder 102. The second variable C_Count is initialized to the current count value of the counter 104 as the count value of the counter 104 when the phase is input once (S1).

After that, the controller 105 generates the On the basis of the award Prize, In order to detect an abnormality of the phase feedback signal line, it is searched whether the initialized first variable Z_Pulse is greater than the sum of the third variable Old_Z and the allowable margin (S2).

Here, the third variable Old_Z counts a current count value when the servo motor 101 is rotated once due to an external influence such as a manual operation of a user when no power is input from the counter 104, and thus the internal memory is counted. If the servo motor 101 is rotated more than one revolution by the value stored in, it is continuously set to the first variable P_Pulse, which is the previous value of the rotation speed, and the allowable margin is different for each system due to the system tolerance.

As a result of the search, if the first variable Z_Pulse is greater than the sum of the third variable Old_Z and the allowable margin, the controller 105 generates a warning sound to generate the warning sound. Prize, The abnormality is found in the feedback signal line of the image (S3).

If the first variable Z_Pulse is smaller than the third variable Old_Z and an allowable margin, the controller 105 determines that Prize, The interrupt is terminated by determining that there is no abnormality in the feedback signal line.

Next, the control unit 105 Prize, Based on up / down count data In order to detect an abnormality of the phase feedback signal line, the first variable Z_Pulse is set to the second variable Old_Z (S4).

In addition, the controller 105 subtracts the second variable C_Count from the first variable Z_Pulse and sets it to the fourth variable Z_temp (S5).

Thereafter, the controller 105 searches whether the fourth variable Z_temp is smaller than the allowable margin or larger than the allowable margin (S6).

That is, the controller 105 generates a warning sound when the fourth variable Z_temp is smaller than the allowable margin or larger than the allowable margin. It is informed that there is an error in the phase feedback signal line (S7).

If the fourth variable Z_temp is less than the allowed margin or not greater than the allowed margin, The interrupt is terminated by determining that the phase feedback signal line is intact.

The controller 105 interrupts every predetermined time and repeats the above process. Prize, Phase feedback signal line or The abnormality of the phase feedback signal line is detected.

Let's look at the above-described process in more detail.

First, if the servo motor 101 has rotated once, the controller 105 initializes the count value of the counter 104 to 3999 and the variable C_Count to 3999, the current count value of the counter 104, in the variable Z_Pulse. .

After that, the controller 105 generates the On the basis of the award Prize, In order to detect an abnormality of the phase feedback signal line, it is searched whether the first variable Z_Pulse is greater than the sum of the third variable Old_Z and the allowable margin.

Here, the third variable Old_Z is 3999 as the current count value when the servo motor 101 is rotated once due to an external influence such as a manual operation of a user when no power is input from the counter 104, and the servo motor ( When 101) is rotated more than one revolution, it is continuously set to the first variable P_Pulse, which is the previous value of the revolution number, and the allowable margin is 100 to 200 pulses as the system tolerance, but is different for each system.

At this time, the Prize, If the upper feedback signal line is open / short, the first variable Z_Pulse has a value greater than 3999 (for example, 4500).

Therefore, as a result of the search, the first variable Z_Pulse is larger than the sum of the third variable Old_Z and the allowed margin (45003999 + 100 to 200). Prize, This indicates that there is an error in the feedback signal line on the image.

Also, the Prize, If there is no error in the feedback signal line of the image, the first variable Z_Pulse has 3999.

As a result of the search, the first variable Z_Pulse is smaller than the sum of the third variable Old_Z and the allowable margin (39993999 + 100 to 200). Prize, The interrupt is terminated by determining that there is no abnormality in the feedback signal line.

Next, the control unit 105 Prize, Based on up / down count data In order to detect an abnormality of the phase signal line, the first variable Z_Pulse is set to the third variable Old_Z.

At this time, the Prize, If there is no abnormality in the feedback signal line of the image, the first variable Z_Pulse has 3999 and the third variable Old_Z has 3999.

In addition, the controller 105 subtracts the second variable C_Count from the first variable Z_Pulse (3999-3999) and then sets it to the fourth variable Z_temp.

Thereafter, the controller 105 searches whether the fourth variable Z_temp is smaller than the allowable margin or larger than the allowable margin.

That is, since the search result, the fourth variable Z_temp is not smaller than the allowed margin or greater than the allowed margin. The interrupt is terminated by determining that the phase feedback signal line is intact.

After that, the control unit 105 is supplied with power. Prize, Phase or An interrupt for searching for an abnormal signal line is repeatedly performed every predetermined time.

As described above, the apparatus for detecting an abnormality of the feedback signal line of the servo motor encoder according to the present invention detects an abnormality of the feedback signal line due to the open / short of the encoder feedback signal line and generates an alarm sound, thereby generating an abnormal input signal. There is an effect that can prevent the runaway (maximum RPM rotation of the servo motor) phenomenon of the servo motor.

In addition, since there is no need to add a gate or the like as in a line drive servo motor encoder, there is an advantage of reducing manufacturing costs.

Claims (8)

In the open collector servo motor encoder having a servo motor, A pulse generator for detecting a rotation direction of the servo motor by searching an input order of feedback signals generated by the encoder and generating an up / down pulse according to the detection result; A counter for counting up / down the generated up / down pulses; And a control unit which reads the up / down counted up / down pulse data and the feedback signal of the encoder to search for an abnormality of the feedback signal line of the encoder and generates an alarm sound according to the search result. Feedback signal line abnormality detection device. In the detection method of the feedback signal line abnormality of the servo motor encoder, Searching the input sequence of the feedback signal generated by the encoder to detect a rotation direction of the servo motor and outputting an up / down pulse according to the detection result; Up / down counting the output up / down pulses, reading up / down counted up / down pulse data and feedback signals of the encoder to search for abnormality of a feedback signal line, and generating a beep according to the search result. Method for detecting the presence or absence of feedback signal line abnormality of the servo motor encoder, characterized in that consisting of. The method of claim 2, The generating of the warning sound may include: counting up / down the output up / down pulse and outputting the up / down counted up / down pulse data by outputting the up / down pulse. Prize, On the basis of the phase And detecting the abnormality of the feedback signal line by searching the phase. The method of claim 3, remind Phase is a signal output from the encoder in accordance with the forward (clockwise) rotation of the servo motor, Phase is a signal output from the encoder according to the reverse direction when the servo motor rotates (counterclockwise), The phase is a feedback signal line abnormality detection method of the servo motor encoder, characterized in that the signal generated by the encoder when one rotation of the servo motor. The method according to claim 4, remind The phase is a feedback signal line abnormality detection method of the servo motor encoder, characterized in that one pulse per rotation of the servo motor. The method of claim 2, The generating a warning sound is a feedback signal generated from the encoder. On the basis of the award Prize, And detecting the abnormality of the feedback signal line by searching the phase. The method of claim 2, The generating of the warning sound may include comparing whether the counter value Z_Pulse of the counter when the servo motor rotates one rotation is greater than the sum of the allowance margin and the count value Old_Z that occurs due to external influences, such as by a user's operation. Steps; As a result of the comparison, when the count value Z_Pulse of the counter in one revolution of the servo motor is greater than the sum of the count value Old_Z and the allowable margin in one revolution due to external influences such as a user's operation, Prize, And detecting the abnormality of the phase feedback signal line, wherein the feedback signal line is abnormal. The method of claim 2, The generating of the warning sound may include comparing whether the value obtained by subtracting the count value (C_Count) of the current counter from the count value (Z_Pulse) of the counter at one rotation of the servo motor is less than an allowable margin or greater than an allowable margin. ; As a result of the comparison, if the value obtained by subtracting the count value (C_Count) of the current counter from the counter value Z_Pulse at one revolution of the servo motor is smaller than the allowed margin or larger than the allowed margin, And detecting the abnormality of the phase feedback signal line, wherein the feedback signal line is abnormal.