JP3444074B2 - Operating state monitor of machine powered by motor and abnormality diagnosis method of machine powered by motor - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an operating state monitor device for monitoring the operating state of a machine which uses a motor as a power source, and an abnormality diagnosis method for diagnosing the state of the machine. Regarding

[0002]

2. Description of the Related Art Conventionally, as a method for diagnosing whether or not there is an abnormality in a machine having a motor as a power source, it has been disclosed in Japanese Patent Laid-Open Nos. 6-304800 and 63-33398. As described above, there are a vibration method, an ultrasonic method, a stress ultrasonic method, etc., and measuring devices are commercially available.

[0003]

The application range of such a conventional diagnostic method and the measuring device therefor is a stationary rotating machine such as a fan of a pump or an intake / exhaust device, or a vacuum device, a pressure vessel, or a motor unit. It is for detecting an abnormality of a machine that rotates at a relatively high speed, and is suitable for diagnosing such a machine.

However, in a complex motion machine in which the rotational motion of the motor is converted into a reciprocating motion, intermittent motion is performed, and shock load is applied, the load, displacement, speed, acceleration, etc., change sequentially. It was not possible to detect the presence or absence of an abnormality in the entire machine and diagnose it by simply managing the displacement amount trend.

Therefore, an object of the present invention is to detect an abnormality in a machine that uses a motor as a power source, and in particular, to detect an abnormality in a composite operation machine having a reciprocating operation part and to estimate the location of the abnormality. It is an object of the present invention to provide a monitoring device that monitors the operating state of the above, and also provide an abnormality diagnosis method for detecting the presence or absence of such a machine abnormality and estimating the location of the abnormality.

[0006]

In order to achieve the above object, the present invention according to claim 1 uses a motor as a power source and transmits at least a rotary motion by the motor,
An operation state monitoring device for monitoring an operation state of a machine having a movement direction changing means for changing the rotation movement of the rotating shaft into a reciprocating movement and an operation portion connected to the movement direction changing means for reciprocating movement. There is a rotary axis movement amount measuring means for measuring the movement amount of the rotary shaft, a motor power consumption measuring means for measuring the power consumption of the motor, and a movement part movement amount measuring means for measuring the movement amount of the movement part. A motor power consumption storage unit that stores the power consumption of the motor measured by the motor power consumption measurement unit; and an operation amount storage unit that stores the operation amount of the operation part measured by the operation part operation amount measurement unit; The power consumption of the motor measured by the motor power consumption measurement means is stored in the power consumption storage means at regular intervals of the rotation axis movement amount measured by the rotation axis movement amount measurement means. , And the operation amount of the operating locality of the operation site operation amount measuring means for measuring at regular intervals the rotation axis operation amount which the rotary shaft operation amount measuring means measures, is stored in the operation quantity storage means, it has been stored Obtained from the measurement results
The power consumption of the motor with respect to the movement amount of the movement part
Is a control means for displaying the change in the above condition together with a predetermined diagram, and an operating condition monitoring device.

According to a second aspect of the present invention, in the operation state monitoring device according to the first aspect, the machine is a press machine transporting apparatus, and holds the work by the reciprocating motion part. It is an operating condition monitoring device characterized by the above.

In order to achieve the above object, the present invention according to claim 3 uses a motor as a power source and converts at least a rotary shaft for transmitting a rotary motion by the motor and a rotary motion of the rotary shaft into a reciprocating motion. A motion direction changing means, and a motion part connected to the motion direction changing means for reciprocating motion;
An abnormality diagnosis method for diagnosing the state of a machine having, wherein the operation amount of the rotating shaft is measured, and the power consumption of the motor is measured at regular intervals of the measured operation amount of the rotating shaft, The waveform of the power consumption of the motor obtained by the measurement is
The rotation is measured when it is determined that the machine has an abnormality when the power consumption is out of a predetermined power consumption range according to the upper limit waveform and the lower limit waveform, and the motor power consumption when the abnormality is determined is measured. From the operation amount of the shaft, the operation point operating at the operation amount of the rotating shaft is obtained from the operation diagram of the predetermined operation point, and it is estimated that the obtained operation point is abnormal. An abnormality diagnosis method characterized by the above.

A fourth aspect for achieving the above object
According to the present invention described above, a motor is used as a power source, at least a rotary shaft for transmitting rotary motion by the motor, a motion direction changing means for converting the rotary motion of the rotary shaft into a reciprocating motion, and a connection to the motion direction changing means. A reciprocating motion part, and an abnormality diagnosis method for diagnosing a state of a machine having, wherein the operation amount of the rotating shaft is measured, and at a constant interval of the measured operation amount of the rotating shaft, The power consumption of the motor and the operation amount of the operation part are measured and obtained by the measurement .
Power consumption waveform of the motor which is the upper limit of the waveform and lower wave
If deviated from a predetermined power range by the shape, it is determined that there is an abnormality in the machine, the operation amount of the rotary shaft, wherein the motor power consumption was measured when it is determined that there is the abnormality, An abnormality diagnosing method characterized in that an operation portion operating at the operation amount of the rotation axis is obtained from the operation amount of the measured operation portion, and that the obtained operation portion has an abnormality. .

According to a fifth aspect of the present invention, in the abnormality diagnosing method according to the third or fourth aspect, the predetermined power consumption range is one rotation of the rotating shaft as one measurement. The measured motor power consumption is sequentially stored, the frequency distribution of the measured motor power consumption is determined for each operation amount of the rotating shaft based on the memory, and the power consumption range is determined from the determined frequency distribution. It is a method for diagnosing abnormalities that is characterized by:

Further, the present invention according to claim 6 provides the invention according to claim 3.
The abnormality diagnosis method according to any one of claims 1 to 5, wherein the machine is a press machine conveyance device and holds a work by the reciprocating motion part. Is.

[0012]

The present invention constructed as described above has the following effects for each claim. According to the present invention as set forth in claim 1, the power consumption of the motor is measured, and the measurement result is stored at a constant interval of the rotary shaft motion amount for transmitting the rotary motion of the motor, and the rotary shaft motion amount is stored. The amount of movement of the moving part is stored at regular intervals, and the stored measurement results
The motor with respect to the movement amount of the movement part obtained from
The change in power consumption of the
Since the display is made, the relationship between the change in power consumption and the operation position of the operation part can be known with reference to the operation amount of the rotating shaft.
Therefore, even in a complex motion machine in which the load, displacement, speed, acceleration, etc., change sequentially, for example, the location of the motion part is estimated when the motor power consumption changes due to some abnormality in the machine. It becomes possible to do.

According to the second aspect of the present invention, in the press machine transporting apparatus, similarly to the first aspect of the invention, the power consumption of the motor is measured and the measurement result is used as the rotary shaft operation amount. Since it was decided to memorize at a fixed interval of,
The relationship between the position where the power consumption has changed and the operating position of each operating part of the press machine transport device is known, and the same effect as the effect of the invention according to claim 1 is obtained.

According to the third aspect of the present invention, the power consumption of the motor is measured on the basis of the operation amount of the rotating shaft, and the measured power consumption waveform is within a range predetermined by the upper and lower limit waveforms. If there is an abnormality, it is determined that there is an abnormality, and the operation site at that time is determined from the operation diagram that is determined in advance based on the operation amount of the rotating shaft, and it is assumed that this is an abnormal site. Even for complex motion machines in which the speed, acceleration, etc. change sequentially, it is possible to detect abnormalities such as machine failures and malfunctions at an early stage, and even estimate the location of the abnormality. Work efficiency can be improved.

According to the fourth aspect of the present invention, the power consumption of the motor and the operation amount of the operating portion are measured with reference to the operation amount of the rotating shaft, and the measured power consumption waveforms are the upper and lower limits.
If the waveform deviates from the predetermined range, it is judged that there is an abnormality, and the operating part at that time is calculated from the operating amount of the operating part measured based on the operating amount of the rotation axis, and this is estimated as the abnormal part. Since it was decided to do so, even in the case of a compound motion machine in which load, displacement, speed, acceleration, etc. change sequentially, the occurrence of an abnormality such as a machine failure or malfunction will occur early, and even the estimation of the location of the abnormality will occur. This makes it possible to improve the efficiency of machine maintenance and inspection work.

According to a fifth aspect of the present invention, in the abnormality diagnosing method according to the third or fourth aspect, a criterion for determining whether or not there is an abnormality is to store measured motor power consumption and obtain it from its frequency distribution. As a result, the changes over time of the machine,
When the work handled by the machine is changed, the change in the motor power consumption due to a factor different from the machine abnormality such as the change in the motor power consumption caused by the change in the load applied to the machine is not considered abnormal. Therefore, more efficient abnormality diagnosis can be performed.

According to the present invention described in claim 6, by applying the invention described in any one of claims 3 to 5 to a conveying device for a press machine, a composite device such as a conveying device for a press machine is obtained. It is possible to efficiently perform abnormality diagnosis of the operating machine.

[0018]

DETAILED DESCRIPTION OF THE INVENTION Referring to the accompanying drawings,
An embodiment of the present invention will be described.

FIG. 1 is a block diagram for explaining an operation state monitor device (hereinafter, simply referred to as a monitor device) to which the present invention is applied, and FIG. 2 monitors the operation state by this monitor device. FIG. 3 is a perspective view showing a work transfer machine of a transfer press machine for diagnosing whether or not there is any abnormality. In addition, the same code | symbol was attached | subjected about the member which has the same function.

This monitor device includes a power measuring device 11 (motor power consumption measuring means) for measuring power consumption of a motor 51 of a machine to be monitored, and a rotation angle measuring device 12 (rotating shaft operation) for measuring a rotation angle of a rotary shaft 53. Quantity measuring means), operating part 5
5 receives signals from the motion amount sensor 13 (motion part motion amount measuring means), the power measuring device 11, the rotation angle measuring device 12, and the motion amount sensor 13 that measure the motion amount of the motor 5, and the power consumption of the motor 51 and the motion region 55. Is stored in the storage device 15 (motor power consumption storage means and operation amount storage means) on the basis of the rotation angle of the rotary shaft 53, and includes a monitor device main body 14 (control means) for performing statistical processing and the like. The power consumption of the motor 51 and the operation amount of the operation portion 55 are stored in the storage device 15 for each predetermined rotation angle of the rotation angle of the rotation shaft 53 measured by the rotation angle measuring device 12 by the operation of the device body 14. It

As the monitor device main body 14, for example, a personal computer is used, and the display 1 for displaying the monitor result.
6 and a printer (not shown) are provided. Also,
The storage device 15 is preferably a hard disk, a magneto-optical disk (MO), a magnetic tape or the like when it is necessary to store data for a long time, but a floppy disk or any other storage medium is used. Well,
It is not particularly limited.

Next, an abnormality diagnosing method using this monitor device will be described. Here, the work transfer machine of the transfer press machine shown in FIG. 2 (hereinafter, simply referred to as a transfer machine) to be diagnosed. The outline of is explained.

In the transfer machine, the driving force of the motor 51, which is a power source, is transmitted to the rotary shaft 53 through the speed reducer 52, and the rotation of the rotary shaft 53 is converted into reciprocating motion by the crank / cam mechanism 60, and the feed is performed. The bar 70 is in operation (the motor 51 is shown as a symbol because it is not in the position shown in this drawing).

The motor 51 is a three-phase AC motor and is a low-speed rotation motor having a rotation speed of 300 RPM or less. The motor 51 is provided with a power meter 11 for measuring its power consumption. In addition, the power of the motor 51 is reduced by the speed reducer 52.
The rotary shaft 53 that transmits through the rotary shaft 53 is provided with a rotary angle measuring device 12 such as a pulse encoder for measuring the rotary angle of the rotary shaft 53 as an operation amount.

The crank / cam mechanism 60 includes a crank 61.
The cam 62 converts the rotational motion of the rotary shaft 53 into a reciprocating motion to intermittently reciprocate the feed bar 70, and also causes the crank 63, the cam 64, and the subsequent operating mechanism to move up and down (vertical reciprocating motion). Then, one rotation of the rotary shaft 53 causes one cycle of the operation of the feed bar 70. Further, each crank is provided with a damper 65 using pneumatic pressure or a hydraulic cylinder so that the feed bar 70 operates smoothly.

The feed bar 70 is the operating portion in FIG. 1, and is provided with a cross bar 71 bridging both feed bars 70, and each work piece 75 is vacuum-sucked to each cross bar 71. A vacuum cup 72 is provided, and the work 75 sent from the work pickup device 80 is sequentially transported on the moving bolster 90 by the operation of the feed bar 70. The feed bar 70 is provided with a movement amount sensor 13 for measuring the movement amount,
The amount of reciprocating motion and the amount of vertical motion are measured. As the movement amount sensor 13, for example, the feed bar 7
A limit switch for measuring the output limit and the limit limit of the damper 65 provided on each crank for operating 0, a sliding resistance whose resistance value changes following the movement of the feed bar 70, and the like.

In the abnormality diagnosis of the transport machine, first, the rotation angle of the rotary shaft 53 is measured by the rotation angle measuring device 12 under the control of the monitor device main body 14, and every time the measured rotation angle becomes 0.5 degrees. That is, the power consumption measured by the power meter 11 and the operation amount of the feed bar 70 measured by the operation amount sensor 13 are stored in the storage device 15 at intervals of 0.5 degrees of the rotation shaft 53.

Normally, when an abnormality occurs in the operation of the machine, an extra load is applied to the operating part, and conversely, the load applied to the part that has been loaded up until now is removed. The power consumption of the motor changes.

Here, an important point is that the power consumption and the operation amount are stored with reference to the rotation angle of the rotation shaft. In this way, if the rotation angle of the rotation shaft is used as a reference, it is possible to correlate the movement amount (motion position) in one cycle of the feed bar 70 corresponding to the rotation angle from the rotation angle.
The abnormal portion can be estimated from the change in power consumption as described later.

However, the power consumption of the motor constantly changes in accordance with the movement of the operating part in the complex operating machine in which the load, displacement, speed, acceleration, etc., change sequentially, so whether it is a normal change or an abnormal condition. It is unknown whether the change is due to the occurrence of. Therefore, a standard for determining whether the operation is normal is necessary.

Therefore, in the present embodiment, one cycle of the feed bar 70, that is, the measurement during one rotation of the rotary shaft 53 is stored as one measurement in the storage device 15, and the stored measurement result is stored. Is used as a reference by statistically processing.

FIG. 3 is a graph showing the measurement results of the power consumption of the motor. As shown in the figure, the power consumption is stored in 0.5 degree increments for each measurement.
Then, a frequency distribution of the stored power consumption is obtained for each rotation angle, and an upper limit and a lower limit are determined. For example, the frequency distribution at a certain angle A is shown in FIG. Such a frequency distribution table is created for every rotation angle in increments of 0.5, and values such as σ and 3σ are determined as upper and lower limits for each rotation angle . The upper and lower limits thus determined
The limit is shown as a waveform as shown in FIG. 5, and a range in which the variation in the normal state is taken into consideration is determined.

If the power consumption of the motor is within the range of the upper and lower limits (FIG. 5) thus obtained, it can be diagnosed that the machine has no abnormality.

Next, the estimation of the location where the abnormality has occurred will be described.

FIGS. 6 and 7 show waveforms (power waveforms) of the power consumption when there is an abnormality for each rotation angle of the rotation axis, and the operation amount of the feed bar 70 for each rotation angle that is simultaneously collected at this time. It is the drawing which plotted. The operation amount is plotted separately in the feed direction and the vertical (lift) direction.

First, as can be seen from FIG. 6, an angle of about 13
An abnormal waveform of power consumption is seen from around 5 degrees to 270 degrees. Then, at this portion, the feed bar 70 is not operating in the feed direction or the lift direction, and the cam is in the idle state. Therefore, as the abnormal point,
A portion not related to the operation of the feed bar 70 itself, for example, a gear in the speed reducer 52 or a gear for transmitting power from the rotary shaft 53 to the crank / cam mechanism 60 or an abnormality on the cam surface is estimated.

Next, in the case shown in FIG. 7, the angle is about 27.
An abnormal waveform of power consumption is seen from 5 degrees to 315 degrees. At this portion, the feed bar 70 is intruding in the feed direction and descending in the lift direction, so it is presumed that there is some abnormality in the intruding operation or the descending operation. That is, the beginning of the descending operation in the lift direction and the beginning of the abnormal waveform of the power consumption are almost the same. Therefore, it can be determined that there is a high probability that there is an abnormality in the descending motion. That is, in this case, it can be presumed that the occurrence of galling in the sliding portion during the lowering operation of the feed bar 70, the abnormality in the gear portion for performing the lowering operation, and the like.

Then, as shown in FIGS. 6 and 7,
When no abnormality is found in the operation of the feed bar 70 itself, these abnormalities cannot be easily discerned from the operation of the transport machine itself. Anomalies can be found and the location of anomalies can be estimated.

In the present embodiment described above, the operation of the feed bar 70, which is the operating part of the machine, is measured by the sensor and is superposed on the motor power consumption, so that an abnormality occurs when there is an abnormality. I estimated the location,
Not limited to this, for example, the operation of the operation part may not be actually measured, and the design of the operation diagram may be simply superimposed on the measurement result of the motor power consumption to estimate the location of the abnormality as described above.

Further, when measuring the power consumption of the motor, the rotation angle of the rotary shaft is used as a reference. For example, instead of the rotation angle of the rotary shaft, the rotation angle or the rotation speed of the motor itself is used as a reference. Good.

[Brief description of drawings]

FIG. 1 is a block diagram for explaining a monitor device to which the present invention is applied.

FIG. 2 is a perspective view showing a work transfer machine of a transfer press machine.

FIG. 3 is a diagram showing a result of measuring motor power consumption by the monitor device.

4 is a drawing showing a frequency distribution at an angle A in FIG.

FIG. 5 is a diagram showing upper and lower limits of motor power consumption, which is a criterion for abnormality diagnosis to which the present invention is applied.

FIG. 6 is a diagram showing an example of an abnormality diagnosis result to which the present invention is applied.

FIG. 7 is a diagram showing another example of the abnormality diagnosis result to which the present invention is applied.

[Explanation of symbols]

11 ... power meter, 12 ... Rotation angle measuring device, 13 ... Motion amount sensor, 14 ... Monitor device body, 15 ... Storage device.

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuya Seo 2 Takara-cho, Kanagawa-ku, Yokohama, Kanagawa Nissan Motor Co., Ltd. (56) Reference JP-A-6-304800 (JP, A) JP-A-8 -1384 (JP, A) JP 6-349261 (JP, A) JP 6-331507 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G05B 23/02 B21D 43/00 B30B 15/28

Claims (6)

(57) [Claims] 1. A motor as a power source, a rotary shaft for transmitting at least a rotary motion of the motor, a motion direction changing means for converting the rotary motion of the rotary shaft into a reciprocating motion, and the motion direction changing means. And reciprocating motion parts,
An operating state monitoring device for monitoring an operating state of a machine having: a rotating shaft operating amount measuring unit for measuring an operating amount of the rotating shaft; and a motor power consumption measuring unit for measuring power consumption of the motor. An operating part operating amount measuring means for measuring an operating amount of the operating part; a motor power consumption storing means for storing the power consumption of the motor measured by the motor power consumption measuring means; An operation amount storage unit that stores the measured operation amount of the operation part, and a constant interval of the rotation axis operation amount that the rotation axis operation amount measurement unit measures the power consumption of the motor measured by the motor power consumption measurement unit. A rotation axis movement amount stored in the power consumption storage means and measured by the rotation axis movement amount measurement means for the movement amount of the movement portion measured by the movement portion movement amount measurement means At regular intervals, is stored in the operation quantity storage means, the measurement results from the obtained of the operation site is stored
The change in the power consumption of the motor with respect to the operation amount is determined in advance.
An operating condition monitoring device comprising: a control means for displaying together with a diagram which is set . 2. The operating state monitor device according to claim 1, wherein the machine is a transporting device for a press machine, and holds the work by the reciprocating motion part. 3. A motor as a power source, a rotary shaft for transmitting at least a rotary motion of the motor, a motion direction changing means for converting the rotary motion of the rotary shaft into a reciprocating motion, and connected to the motion direction changing means. And reciprocating motion parts,
An abnormality diagnosis method for diagnosing a state of a machine having, wherein the operation amount of the rotating shaft is measured, the power consumption of the motor is measured at regular intervals of the measured operation amount of the rotating shaft, The waveform of the power consumption of the motor obtained by the measurement is the upper limit.
It is determined that the machine has an abnormality when it is out of the power consumption range determined in advance by the waveform and the lower limit waveform, and the motor power consumption at the time of determining that there is the abnormality is measured for the rotary shaft. From the operation amount, the operation point that is operating at the operation amount of the rotation axis is obtained from the operation diagram of the predetermined operation point, and it is estimated that the obtained operation point is abnormal. Characteristic abnormality diagnosis method. 4. A rotary shaft that transmits at least a rotary motion of the motor using a motor as a power source, a motion direction changing means for converting the rotary motion of the rotary shaft into a reciprocating motion, and the motion direction changing means. And reciprocating motion parts,
An abnormality diagnosing method for diagnosing a state of a machine, comprising: measuring the operation amount of the rotating shaft, and measuring the power consumption of the motor and the operation at regular intervals of the measured operation amount of the rotating shaft. The amount of movement of the part is measured, and the waveform of the power consumption of the motor obtained by the measurement is the upper limit.
It is determined that there is an abnormality in the machine when the power consumption deviates from the power consumption range determined in advance by the waveform and the lower limit waveform, and the motor power consumption when the abnormality is determined is measured in the rotary shaft. Abnormality characterized by obtaining from the operation amount the operation portion operating at the operation amount of the rotation axis from the operation amount of the measured operation portion and estimating that the obtained operation portion has an abnormality Diagnostic method. 5. The predetermined power consumption range is such that one rotation of the rotary shaft is measured once, and the measured motor power consumption is sequentially stored, and the operation of the rotary shaft is based on the stored memory. The abnormality diagnosis method according to claim 3 or 4, wherein a frequency distribution of the measured motor power consumption is obtained for each amount, and the power consumption range is determined from the obtained frequency distribution. 6. The machine according to claim 3, wherein the machine is a transfer machine for a press machine, and holds the work by the reciprocating motion part. Abnormality diagnosis method.