JP2005237093A - Method and apparatus for inspecting ac servo motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and an apparatus for inspecting an AC servo motor wherein a malfunction can be grasped and quality can be determined quickly and accurately based on an encoded serial communication signal outputted from an encoder. <P>SOLUTION: When rotational position information and abnormal state information are inputted as an encoded signal in accordance with the RS422 standard from the encoder 13 on an AC servo motor 10 to the analyzing portion 31 of a signal analyzer 30, the analyzing portion 31 converts them into digitalized information, and displays a numeric value on a display portion 32. Therefore, the grasp of a malfunction and the determination of quality can be quickly and accurately carried out. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an inspection method and an inspection apparatus for an AC servo motor used for, for example, an industrial robot.

  Conventionally, AC servo motors (DC brassless servo motors) used for driving industrial robots and various processing machines do not require an origin return operation, so they are absolute for detecting the absolute rotational position of the rotor relative to the stator. Those equipped with a type encoder are widespread.

  Such an encoder not only outputs pulse data (incremental pulse signal) for detecting the position during one rotation, but also information on the absolute rotation position of the rotor (position and number of rotations during one rotation). In addition, there is known one that outputs information for notifying its own abnormal state as serial communication data.

  For example, when a failure occurs in an AC servo motor equipped with such an encoder at a factory site, or when there is a suspicion of failure, the incremental Paris signal or serial communication data is generally visually checked with an oscilloscope or a communication monitor. Checks are performed to identify defects and determine whether the product is good or bad after maintenance.

  However, in the conventional AC servo motor inspection method, it is relatively easy to check the incremental Paris signal, but serial communication data is a coded signal. There is a problem that it occurs or takes time for the determination.

  The present invention has been made in view of the above points, and based on the serial communication coded signal output from the encoder, an AC servo capable of quickly grasping a defect and determining whether it is good or bad It is an object of the present invention to provide a motor inspection method and inspection apparatus.

In order to achieve the above object, in the inspection method of the invention according to claim 1,
An encoder (13) that detects the rotational position of the rotor (12) that can rotate with respect to the wound stator (11) and outputs the detected position information and information on the abnormal state as a coded signal is provided. An inspection method for an AC servo motor (10),
An information conversion step (S101) for converting the coded signal output from the encoder (13) into digitized information;
And a display step (S106) for displaying the digitized information converted in the information conversion step.

  According to this, in the display step (S106), not only the position information but also information relating to the abnormal state can be displayed as numerical information. Therefore, it is possible to quickly grasp the defect and determine whether the product is good or not with high accuracy.

  In the inspection method according to the second aspect of the present invention, the digitized information is numerically displayed in the display step (S106).

  According to this, the display is extremely easy, and the display means (32) can be simplified.

  The inspection method of the invention described in claim 3 is characterized in that the information conversion step (S101) is executed while rotating the rotor (12) by the external rotation driving means (40).

  According to this, in the display step (S106), it is possible to display information relating to the abnormal state of the encoder (13) alone as numerical information.

  In the inspection method according to the fourth aspect of the invention, the information conversion step (S101) is performed while feeding the windings (11a, 11b, 11c) of the stator (11) and rotating the rotor (12). It is characterized by that.

  According to this, it is possible to display information regarding the abnormal state as information obtained by quantifying the relationship between the rotational position of the rotor (12) and the encoder (13).

  In the inspection method according to the fifth aspect of the invention, the information conversion step (S101) is performed while rotating the rotor (12) by the external rotation driving means (40), and then the winding ( 11a, 11b, and 11c), and the rotor (12) is rotated and executed.

  According to this, first, information regarding the abnormal state of the encoder (13) alone is displayed as numerical information, and after checking the abnormal state of the encoder (13), the rotational position of the rotor (12) and the encoder (13) are displayed. Thus, the information regarding the abnormal state can be displayed as numerical information, and the abnormal state corresponding to the rotational position of the rotor (12) can be confirmed.

  In the inspection method according to the sixth aspect of the invention, in the information conversion step (S101), the encoded signal output from the encoder (13) in accordance with the RS422 standard is converted.

  According to this, it is possible to quickly and accurately inspect the AC servo motor (10) including the encoder (13) that outputs serial communication data of the RS422 standard that is excellent in transmission speed and transmission distance.

Moreover, in the inspection apparatus of the invention according to claim 7,
An encoder (13) that detects the rotational position of the rotor (12) that can rotate with respect to the wound stator (11) and outputs the detected position information and information on the abnormal state as a coded signal is provided. An inspection apparatus for an AC servo motor (10),
Information converting means (31) for converting the coded signal output from the encoder (13) into digitized information;
It is characterized by comprising display means (32) for displaying the digitized information converted by the information conversion means (31).

  According to this, the inspection method for an AC servo motor according to claim 1 can be performed.

  In the inspection apparatus according to the eighth aspect of the present invention, the display means (32) displays the digitized information numerically.

  According to this, the inspection method for an AC servo motor according to claim 2 can be performed.

  The inspection apparatus according to claim 9 further includes an external rotation driving means (40) for rotating the rotor (12) when a coded signal is output from the encoder (13). It is said.

  According to this, the inspection method for an AC servo motor according to claim 3 can be performed.

  In the inspection apparatus according to the tenth aspect of the present invention, when the encoded signal is output from the encoder (13), power is supplied to the windings (11a, 11b, 11c) of the stator (11) and the rotor is supplied. A drive circuit (50) for rotating (12) is provided.

  According to this, the inspection method for an AC servo motor according to claim 4 can be performed.

In the inspection apparatus according to the eleventh aspect,
An external drive means (40) for rotating the rotor (12) when a coded signal is output from the encoder (13);
A drive circuit (50) for supplying power to the windings (11a, 11b, 11c) of the stator (11) and rotating the rotor (12) when a coded signal is output from the encoder (13); It is characterized by that.

  According to this, the inspection method for an AC servo motor according to claim 5 can be performed.

  Further, as in the inspection apparatus according to the twelfth aspect of the invention, the drive circuit (50) can have a relatively simple configuration including a DC power source (51), a relay (52), and a sequencer (53). .

  In the inspection apparatus according to the thirteenth aspect of the invention, the information conversion means (31) has a function of inputting an RS422-standard coded signal output from the encoder (13).

  According to this, the inspection method for an AC servo motor according to claim 6 can be performed.

  In addition, the code | symbol in the parenthesis attached | subjected to each said means is an example which shows a corresponding relationship with the specific means as described in embodiment mentioned later.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a block diagram illustrating a schematic configuration of main parts of an inspection apparatus for an AC servomotor 10 according to the present embodiment. FIG. 2 is a schematic diagram showing a connection state of a drive motor 40 that rotationally drives the rotor of the AC servo motor 10 from the outside. FIG. 3 shows a schematic configuration of a drive circuit 50 that drives the AC servo motor 10. It is a schematic diagram.

  An AC servo motor 10 that is an object to be inspected in the present embodiment is used for a robot, an NC machine tool, or the like, for example. As schematically shown in FIG. 3, the AC servo motor 10 includes a stator 11 having coils 11 a, 11 b, and 11 c wound so as to form three phases (U, V, and W phases), respectively. A rotor 12 having a permanent magnet formed with multiple poles (8 poles in this example) and rotating in the stator 11 and an encoder 13 as a rotational position detecting means of the rotor 12 are provided.

  The encoder 13 according to the present embodiment is a so-called absolute type encoder, and is connected to the rotating shaft 12a (see FIG. 1) of the rotor 12. The encoder 13 detects the absolute rotational position of the rotor 12, and detects the detected rotational position information and the The abnormal state information (information on failure etc.) is output.

  Information from the encoder 13 is output as a rotation pulse signal (A phase and B phase signals having a predetermined phase difference so that the rotation direction can be detected) and a high-speed serial communication signal. This high-speed serial communication signal is output at a rate of 1 bit / μs as a coded signal of the Electronic Industries Association (EIA) RS422 standard, which is excellent in terms of transmission speed and transmission distance, and is rotated once every 84 μs. The rotational position data, the rotational speed data, and the status data (abnormal state data) are output as two data (1st data and 2nd data).

  Next, the AC servo motor inspection apparatus according to the present embodiment includes the pulse counter 20, the signal analysis apparatus 30, the drive motor 40 shown in FIG. 2, and the drive circuit 50 shown in FIG.

  The pulse counter 20 receives a rotation pulse signal output from the encoder 13 of the AC servomotor 10. The pulse counter 20 checks the number of pulses per motor rotation based on the input signal, and the count unit 21. And a display unit 22 for displaying the count numbers of the A phase and the B phase checked. The pulse counter 20 also includes an output terminal unit 23 that outputs a count value and pulse waveform data to a data recorder and a waveform observation device.

  On the other hand, the signal analysis device 30 receives a high-speed serial communication signal output from the encoder 13 of the AC servo motor 10. The signal analysis device 30 includes an analysis unit 31 including a CPU that analyzes the input signal, and an analysis unit 31. And a display unit 32 as display means including an LCD or the like for displaying the analyzed data.

  The drive motor 40 is a servo motor as an external rotation driving means for rotating the rotor 12 (see FIG. 3) from the outside without supplying power to the stator 11 (see FIG. 3) of the AC servo motor 10. When rotating, the rotating shaft 40 a is connected to the rotating shaft 12 a of the AC servomotor 10 via the coupling 41.

  The drive circuit 50 includes a DC power source 51 as a power supply, a relay 52 for switching a current from the DC power source 51, and a sequencer 53 as a control unit for switching operation of the relay 53. The sequencer 53 sequentially controls the relay 52 to control the energization waveforms to the coils 11 a, 11 b, 11 c of the stator 11, and the rotor 12 performs a predetermined rotation operation on the stator 11.

  Next, the operation of the inspection apparatus of the present embodiment will be described based on the above configuration.

  When inspecting the AC servomotor 10, first, as shown in FIG. 2, the rotary shaft 40a of the drive motor 40 and the rotary shaft 12a of the AC servomotor 10 are connected, and the drive motor 40 is operated to perform AC servo. The rotor 12 (see FIG. 3) of the motor 10 is rotated under a predetermined condition. At this time, the coils 11a, 11b, and 11c (see FIG. 3) of the stator 11 are not energized.

  In this way, the output from the encoder 13 is input to the pulse counter 20 and the signal analyzing device 30 to check the display contents of the display unit 22 and the display unit 32, thereby confirming whether the encoder 13 alone is abnormal or not. To do.

  If there is no abnormality in the encoder 13, the connection between the rotary shaft 40a of the drive motor 40 and the rotary shaft 12a of the AC servo motor 10 is then released, and the drive circuit 50 is connected to the stator 11 as shown in FIG. The coils 11a, 11b, and 11c are connected to operate the sequencer 53, and the rotor 12 is caused to perform a predetermined rotation operation.

  In this way, the output from the encoder 13 is input to the pulse counter 20 and the signal analyzer 30 to check the display contents of the display unit 22 and the display unit 32, and the rotor 12 displayed on the position monitor of the drive circuit 50 (not shown). And the presence or absence of abnormality in the entire AC servo motor 10 is confirmed.

  In short, first, the encoder 13 is inspected alone, and if it is normal, the absolute rotational position reference of the encoder 13 and the rotational position reference of the rotor 12 are then combined, and the AC servomotor 10 Inspect for any abnormalities.

  The operation of the analysis unit 31 of the signal analysis device 30 that inputs the high-speed serial communication signal from the encoder 13 when the AC servomotor 10 is inspected in the above procedure will be described. FIG. 4 is a flowchart showing a schematic operation of the analysis unit 31.

  As shown in FIG. 4, the analysis unit 31 first inputs a high-speed serial communication signal, converts the serial communication coded signal, and converts each bit information into a numerical signal (step S101). Next, the digitized signals are sequentially taken into an internal shift register. The analysis unit 31 incorporates a 16 MHz bit clock, and can accurately read bit information.

  The analysis unit 31 returns to step S101 until 1st data is detected in the shift register. When the 1st data is detected in the shift register (step S102), the 1st data is latched in the storage area (step S103).

  After step S103 is executed, the process returns to step S101 until 2nd data is detected in the shift register. At this time, steps S102 and S103 are not executed. When 2nd data is detected in the shift register (step S104), the 2nd data is latched in the storage area (step S105).

  The analysis unit 31 displays data on the display unit 32 based on the pair of 1st data and 2nd data latched in steps S103 and S105 (step S106).

  For example, as shown in FIG. 5, the display section 32 displays numerically the rotational position data during one rotation in the position data display area 33 and numerically displays the accumulated rotational speed data in the rotational speed data area 34. Furthermore, status data (abnormal state data) is numerically displayed in the status data area 35 with “0” and “1”. Examples of display items include system down, overflow, battery error, preset signal, count error, and the like.

  Step S101 is an information conversion process in the present embodiment, and step S106 is a display process in the present embodiment. The analysis unit 31 is information conversion means in the present embodiment.

  According to the above-described configuration and operation, the display unit 32 of the signal analysis device 30 can numerically display the rotation position data during one rotation, the rotation speed data, and the data related to the abnormal state. Therefore, it is possible to quickly grasp (for example, about 2 minutes) and with high accuracy in understanding the defect and determining whether the product is good or bad.

  Moreover, since the display part 32 should just be able to numerically display digitization information, the display part 32 can be made simple. Further, the drive circuit 50 can be a simple one constituted by a DC power source 51, a relay 52 and a sequencer 53.

  Therefore, the inspection apparatus according to the present embodiment can be made relatively small. For example, the inspection apparatus is transported to a place where the AC servo motor is installed at a factory site to quickly inspect the AC servo motor. be able to.

  Further, since the signal analyzing apparatus 30 supports RS422 standard high-speed serial communication, the AC servomotor 10 including the encoder 13 that outputs RS422 standard serial communication data that is excellent in transmission speed and transmission distance can be quickly and easily inspected. It can be performed with high accuracy.

(Other embodiments)
In the above embodiment, the signals input from the encoder 13 to the analysis unit 31 of the signal analysis device 30 are a pair of signals composed of 1st data and 2nd data of the RS422 standard. However, coded signals are input. If it is a thing, it will not be limited to this. For example, an RS232C standard signal may be used, or only one or three or more data may be combined to form an information unit.

  In the above-described embodiment, the entire inspection of the AC servo motor 10 is performed after performing the single inspection of the encoder 13. However, the present invention may be applied to only one of them.

  In the above embodiment, the object to be inspected is a three-phase 8-pole AC servo motor. However, the number of phases and the number of poles of the object to be inspected are not limited thereto.

It is a block diagram which shows the principal part schematic structure of the test | inspection apparatus of AC servomotor 10 in one Embodiment to which this invention is applied. 2 is a schematic diagram showing a connection state of a drive motor 40 that rotationally drives a rotor of an AC servo motor 10 from the outside. FIG. 2 is a schematic diagram showing a schematic configuration of a drive circuit 50 that drives an AC servomotor 10. FIG. 5 is a flowchart showing a schematic operation of the signal analysis device 30 analysis unit 31. It is a figure which shows the example of a display of the signal analysis apparatus 30 display part 32. FIG.

Explanation of symbols

10 AC servo motor 11 Stator 11a, 11b, 11c Coil (winding)
12 rotor 13 encoder 30 signal analysis device 31 analysis section (information conversion means)
32 Display section (display means)
40 Drive motor (external rotation drive means)
50 drive circuit 51 DC power supply 52 relay 53 sequencer S101 information conversion process S106 display process

Claims (13)

An encoder (13) that detects the rotational position of the rotor (12) that can rotate with respect to the wound stator (11) and outputs the detected position information and information on the abnormal state as a coded signal is provided. An inspection method for an AC servo motor (10),
An information conversion step (S101) for converting the coded signal output from the encoder (13) into digitized information;
An AC servomotor inspection method comprising: a display step (S106) for displaying the digitized information converted in the information conversion step.   2. The AC servo motor inspection method according to claim 1, wherein in the display step (S106), the digitized information is numerically displayed.   3. The AC servo motor inspection method according to claim 1, wherein the information conversion step (S101) is executed while rotating the rotor (12) by an external rotation driving means (40).   The information conversion step (S101) is performed while feeding the windings (11a, 11b, 11c) of the stator (11) and rotating the rotor (12). 2. The inspection method for an AC servo motor according to 2.   The information conversion step (S101) is performed while rotating the rotor (12) by the external rotation driving means (40), and then supplying power to the windings (11a, 11b, 11c) of the stator (11). 3. The AC servo motor inspection method according to claim 1, wherein the inspection is performed while rotating the rotor (12).   The said information conversion process (S101) converts the said coded signal output by the RS422 standard from the said encoder (13), It is any one of Claim 1 thru | or 5 characterized by the above-mentioned. AC servo motor inspection method. An encoder (13) that detects the rotational position of the rotor (12) that can rotate with respect to the wound stator (11) and outputs the detected position information and information on the abnormal state as a coded signal is provided. An inspection apparatus for an AC servo motor (10),
Information converting means (31) for converting the coded signal output from the encoder (13) into digitized information;
An AC servo motor inspection apparatus comprising: display means (32) for displaying the digitized information converted by the information conversion means (31).   8. The AC servo motor inspection apparatus according to claim 7, wherein the display means (32) displays the numerical information as a numerical value.   9. The external rotation drive means (40) for rotating the rotor (12) when a coded signal is output from the encoder (13). AC servo motor inspection device.   A drive circuit (50) for rotating the rotor (12) by supplying power to the windings (11a, 11b, 11c) of the stator (11) when a coded signal is output from the encoder (13). The AC servomotor inspection apparatus according to claim 7, further comprising: An external drive means (40) for rotating the rotor (12) when a coded signal is output from the encoder (13);
A drive circuit (50) for rotating the rotor (12) by supplying power to the windings (11a, 11b, 11c) of the stator (11) when a coded signal is output from the encoder (13). An AC servomotor inspection apparatus according to claim 7 or 8, characterized by comprising:   12. The AC servo motor inspection apparatus according to claim 10, wherein the drive circuit includes a DC power source, a relay, and a sequencer.   The information conversion means (31) has a function of inputting a coded signal of the RS422 standard output from the encoder (13), according to any one of claims 7 to 12. The inspection apparatus for the AC servo motor as described.

Images