JP7227436B1 - motor monitoring device - Google Patents

Abstract

A motor monitoring device according to an aspect of the present disclosure includes a rotation speed acquisition unit that acquires the rotation speed of a plurality of motors, an output value acquisition unit that acquires output values of the plurality of motors, and the rotation speed between the motors. and a deviation amount calculation unit that calculates the deviation amount of the output value, and a plurality of markers indicating the combination of the rotation speed and the output value for each motor, one axis for the rotation speed and the other axis for the output value. a graph display unit that plots the graph area in a graph area based on a plurality of time ratings of the motor with respect to an assumed combination of the rotation speed and the output value. a graph area setting unit that divides into a plurality of load areas having different load levels and displays the plurality of load areas in a distinguishable manner; a plotting unit that plots the plurality of markers in the graph area; and a connection line drawing unit that draws a connection line connecting the corresponding markers in different ways.

Description

The present invention relates to motor monitoring devices.

For example, in a motor such as a spindle motor of a machine tool, the load of which can change greatly, there is a risk of overheating due to accumulation of heat if the load continues to be large. Such motors can be set with various time ratings that allow them to run under certain conditions without overheating. As time ratings, for example, JIS-C4034-1 includes a continuous rating that allows continuous operation, a short-time rating that allows operation for a certain period of time (load time) from room temperature, and a certain period of time (load time) within a predetermined cycle time. A repetitive rating, etc., that allows operation for a period of time) is stipulated.

For example, in a machine tool, it is conceivable to grasp the actual operating state of the motor and adjust the set values such as the motor speed so that the margin for overheating can be reduced and the machining can be performed more efficiently. As a means to make it possible to grasp the current operating state of the motor, the current rotation speed and output of the motor are displayed on a graph that displays the lines indicating the above various ratings, with the rotation speed on one axis and the output on the other shaft. A load meter that plots values is known (see Patent Document 1, for example).

JP-A-10-90011

For example, there are devices that drive a plurality of motors under the same conditions, such as multi-spindle machine tools. In such a device, there is a possibility that the set values cannot be appropriately adjusted unless the states of the plurality of motors can be grasped.

A motor monitoring device according to an aspect of the present disclosure includes a rotation speed acquisition unit that acquires rotation speeds of a plurality of motors, an output value acquisition unit that acquires output values of the plurality of motors, and the rotation speed between the motors. and a divergence amount calculation unit that calculates the divergence amount of the output value; and a graph display for plotting in a graph area as a value, wherein the graph display unit plots the graph area based on a plurality of time ratings of the motor for possible combinations of the rotation speed and the output value. a graph area setting unit that divides into a plurality of load areas with different load levels and displays the plurality of load areas in an identifiable manner; a plotting unit that plots the plurality of markers in the graph area; a connection line drawing unit that draws a connection line connecting the markers that correspond in different manners.

According to the present disclosure, it is possible to easily grasp the states of a plurality of motors.

1 is a block diagram showing the configuration of a machine tool including a motor monitoring device according to a first embodiment of the present disclosure; FIG. 2 is a diagram illustrating a display by the motor monitoring device of FIG. 1; FIG.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. FIG. 1 is a block diagram showing the configuration of a machine tool 1 including a motor monitoring device according to the first embodiment of the present disclosure.

The machine tool 1 includes a numerical control device 10 which is an embodiment of a motor monitoring device according to the present invention, a plurality of spindle motors 20, a plurality of rotation speed detectors 21 for detecting the rotation speed of the spindle motors 20, a spindle It comprises a plurality of current detectors 22 that detect the current of the motor 20, a display device 30 that performs screen display according to the numerical controller 10, and an input device 40 that the user uses to input to the numerical controller 10.

Numerical control device 10 has a memory, a processor (CPU), an input/output interface, etc., and can be implemented by one or a plurality of computer devices that execute appropriate control programs. The components of the numerical control device 10 described below are categorized functions (operations of the processor) of the numerical control device 10, and may not be clearly classified in terms of physical configuration and program configuration.

The spindle motor 20 is typically a motor that rotationally drives a cutting tool or a work, and the load can vary depending on the machining conditions, regardless of the number of revolutions. The rotation speed detector 21 and the current detector 22 can each be configured by a well-known sensor.

The display device 30 is a well-known display that performs display according to signals input from the numerical control device 10 . The display device 30 may be configured integrally with the numerical control device 10 . The input device 40 is a device for a user to input information to the numerical control device 10, and may have a known configuration such as a keyboard and a mouse. The input device 40 may also be configured integrally with the numerical control device 10 . Also, the input device 40 may be configured integrally with the display device 30 . Specifically, the display device 30 and the input device 40 may be a single input/output device such as a touch panel.

In this embodiment, the numerical control device 10 includes a program storage unit 11, a motor control unit 12 that controls the operation of motors that drive the drive shaft of the machine tool 1 including the spindle motor 20, and a motor monitoring device according to the present disclosure. and a motor monitoring unit 13 that performs the functions of

The program storage unit 11 stores machining programs executed by the machine tool 1 . The machining program includes a plurality of blocks each designating a unit operation of the machine tool 1 . Each block contains one or more words each consisting of a combination of characters. Generally, each block is first assigned a sequence number to identify the block.

The motor control unit 12 executes the machining procedure described in the machining program by controlling the spindle motor 20 and the motors of the other drive axes of the machine tool 1 according to the machining program. Since the configuration of the motor control unit 12 is the same as that of a well-known numerical control device, detailed description thereof will be omitted.

The motor monitoring unit 13 includes a rotation speed acquisition unit 131, an output value acquisition unit 132, a divergence amount calculation unit 133, a graph display unit 134, a notification unit 135, a stop command unit 136, an override command unit 137, Prepare.

The rotation speed acquisition unit 131 acquires the rotation speed of the spindle motor 20 from the rotation speed detector 21 . The rotation speed acquisition unit 131 may acquire the rotation speed of the spindle motor 20 via the motor control unit 12 .

The output value acquiring unit 132 acquires output values such as a current value, a power value, and a torque value of the spindle motor 20 . In this embodiment, the output value acquisition unit 132 acquires the current value of the spindle motor 20 from the current detector 22, and uses the power value and torque value calculated from the current value as the output value. However, the output value acquiring unit 132 may be configured to use the detected value such as the current value as the output value. The output value acquisition unit 132 may acquire an output value or a value necessary for calculating the output value from the motor control unit 12 . Also, the number of types of output values acquired by the output value acquisition unit 132 may be one, or three or more.

The divergence amount calculator 133 calculates the amount of divergence between the rotational speeds and output values of the spindle motors 20 . The amount of divergence may be calculated as a deviation independently for each of the rotation speed and the output value, or may be calculated as a deviation of values obtained as a function of the rotation speed and the output value.

The graph display unit 134 plots a plurality of markers indicating a combination of rotation speed and output value for each spindle motor 20 in a graph area with rotation speed on one axis and output value on the other axis. The graph display section 134 has a graph area setting section 1341 , a plot section 1342 , a connection line drawing section 1343 , a reference setting section 1344 and a reference selection section 1345 .

The graph area setting unit 1341 displays on the display device 30 a graph area in which one axis is the rotation speed and the other axis is the output value. The graph area setting unit 1341 divides the graph area into a plurality of load areas and displays the plurality of load areas in an identifiable manner. More specifically, the graph area setting unit 1341 divides the graph area into a plurality of load zones with different load levels based on a plurality of time ratings of the spindle motor 20 for possible combinations of rotation speed and output value. Thereby, the user can easily grasp the degree of safety or danger of the operating state of the spindle motor 20 .

The graph area setting unit 1341 preferably displays a plurality of load areas by colors or patterns so that they can be identified. By adding colors or patterns, it is easy to identify which load area a combination of rotation speed and output value belongs to. can be grasped. In addition, by using colors or patterns, such as blue, yellow, and red, which are easy to intuitively recognize the height of the load level in the load area, the degree of risk of the operating state of the spindle motor 20 can be easily grasped.

If the combination of the rotation speed and the output value of the spindle motor 20 is set to the continuous rating or less, the load of the spindle motor 20 can be continuously operated without limitation. For this reason, the upper limit of the load zone with the lowest load level is preferably a curve representing the continuous rating.

The graph area setting unit 1341 sets one of the boundaries of a plurality of load zones, preferably the lower limit of the load zone with the highest load level, to a plurality of time ratings at the same rotation speed (for example, short-time ratings and load time rates with different load time rates). It is preferable to make a line connecting the maximum values of the repetition rate). A combination of rpm and power values plotted in the area beyond this line represents a dangerous power condition that can cause an immediate failure. Conversely, if this boundary is not crossed, it may not pose a problem for a short period of time.

The graph area setting unit 1341 may be configured to select the boundary of at least one of the plurality of load areas according to user input. Specifically, the boundaries of the load area can be selected from among the above continuous ratings, maximum values of multiple time ratings, multiple short-time ratings with different load times, and multiple repetitive ratings with different load time rates. can be configured. As a result, it is possible to set an appropriate load area in consideration of the details of machining to be performed in the machine tool 1, so that the degree of danger of the spindle motor 20 can be grasped more appropriately.

The plotting unit 1342 plots a plurality of markers corresponding to the spindle motors 20 on a one-to-one basis in the graph area. The plotting section 1342 preferably plots the markers in different manners for each corresponding spindle motor 20 . As an example, the plotting unit 1342 can plot the markers in a manner that allows the corresponding spindle motors 20 to be identified by differences in shape, color, pattern, or the like of the markers. In the example shown in FIG. 2, which of the three main shaft motors 20 is specified by the shape of the marker.

Also, the plotting unit 1342 may change the mode of the marker according to the state values of each spindle motor 20, such as the load level, temperature, estimated time until reaching the overheat temperature, and the like. In the example shown in FIG. 2, the load level of the corresponding spindle motor 20 is indicated by the pattern (hatching) of the marker. In this way, the plotting unit 1342 indicates the state values in the form of markers, so that the user can grasp the operating state of the spindle motor 20 from various aspects.

The connection line drawing unit 1343 draws a connection line that connects the corresponding markers in the plot area in different manners according to the amount of divergence. Specifically, the connection line drawing unit 1343 may draw the connection line in different manners depending on whether the amount of deviation exceeds the predetermined allowable amount of deviation. The connecting lines may be drawn in different manners depending on the As a form of the connection line that changes according to the amount of deviation, for example, it is conceivable that the user can grasp the magnitude of the amount of deviation by color, thickness, pattern, or the like. Thereby, the user can easily grasp the motor whose load state is significantly different from that of the other motors 20 .

The connection line drawing section 1343 preferably draws a connection line between the marker of one spindle motor 20 that serves as a reference and another marker. Especially when three or more markers are displayed, it is possible to relatively easily comprehend the states of all the spindle motors 20 by setting the spindle motor 20 as a reference, avoiding complicated display.

The reference setting unit 1344 sets the reference spindle motor 20 so that the number of other spindle motors 20 whose deviation amount is within a predetermined range is maximized. By setting the reference spindle motor 20 in this way, it is possible to clearly display the spindle motors 20 that are significantly different from the others in at least one of the rotation speed and the output value. can be discriminated.

The reference selection unit 1345 provides an interface that allows the user to select the reference spindle motor 20 . An appropriate reference can be set by selecting the spindle motor 20 that serves as the reference based on the user's judgment. For example, by using the spindle motor 20 that has been replaced with a new one as a reference, the degree of deterioration of the other spindle motors 20 can be comprehended relatively appropriately. Further, when there are a plurality of spindle motors 20 having the largest number of other spindle motors 20 whose deviation amount is within the predetermined range in the reference setting section 1344, the reference selection unit 1345 determines that the deviation amount is within the predetermined range. It may be used to allow the user to select a reference motor from among a plurality of spindle motors 20 having the largest number of other spindle motors 20 .

When the deviation amount exceeds a predetermined reported deviation amount, the reporting unit 135 reports to that effect. This makes it possible to inform the user of the possibility that one of the spindle motors 20 is in an abnormal operating state. The notification can typically be made by displaying a warning message on the display device 30, issuing an alarm, turning on a warning light, or the like.

The stop command unit 136 stops the spindle motor 20 when the deviation amount exceeds a predetermined stop deviation amount. As a result, it is possible to prevent the occurrence of defective products caused by an abnormality in one of the spindle motors 20, the spread of the abnormality to other components, and the like.

The override command unit 137 changes the rotation speed of the spindle motor 20 when the deviation exceeds the override deviation. Specifically, the override command unit 137 inputs an override command to the motor control unit 12 when the deviation amount exceeds a predetermined override deviation amount. The override command is a command to reduce the speed of the spindle motor 20 to a speed different from the speed specified by the machining program, for example, to the speed specified by the machining program to achieve a constant ratio of speed.

As described above, the numerical controller 10 according to the present embodiment displays the connection lines in such a manner that the amount of deviation can be determined, so that the user can relatively easily grasp the states of all the spindle motors 20. .

The following additional remarks will be disclosed with respect to the above embodiment and modifications.
(Appendix 1)
A motor monitoring device (10) includes a rotation speed acquisition unit (131) for acquiring rotation speeds of a plurality of motors (20), an output value acquisition unit (132) for acquiring output values of the plurality of motors (20), A divergence calculation unit (133) for calculating the divergence of the rotation speed and the output value between the motors (20), and a plurality of markers indicating the combination of the rotation speed and the output value for each motor (20). and a graph display unit (134) for plotting the number of rotations and the output value on the other axis in a graph area. ) based on a plurality of time ratings, a graph area setting unit (1341) that divides the graph area into a plurality of load areas with different load levels and displays the plurality of load areas in an identifiable manner; and a connection line drawing unit (1343) for drawing connection lines connecting corresponding markers in different modes according to the amount of divergence.

(Appendix 2)
The plotting unit (1342) may plot markers in different manners for each corresponding motor (20).

(Appendix 3)
3. The motor monitoring device according to claim 1, wherein the connection line drawing unit (1343) draws the connection line in different manners depending on whether the amount of deviation exceeds a predetermined allowable amount of deviation.

(Appendix 4)
3. The motor monitoring device according to claim 1 or 2, wherein the connection line drawing unit (1343) draws the connection line in different manners according to the ratio of the amount of deviation and the predetermined allowable amount of deviation.

(Appendix 5)
The motor monitoring device (10) may further include a notification unit (135) that notifies when the deviation amount exceeds a predetermined notification deviation amount.

(Appendix 6)
The motor monitoring device (10) may further include a stop command section (136) that stops the motor (20) when the deviation exceeds a predetermined stop deviation.

(Appendix 7)
The motor monitoring device (10) may further include an override command section (137) that changes the rotation speed of the motor (20) when the deviation exceeds a predetermined override deviation.

(Appendix 8)
The connection line drawing unit (1343) may draw a connection line between the marker of one reference motor (20) and another marker.

(Appendix 9)
The graph display unit (134) further has a reference setting unit (1344) for setting the reference motor (20) so that the number of other motors (20) whose deviation amount is within a predetermined range is maximized. good too.

(Appendix 10)
The graph display section (134) may further have a reference selection section (1345) that allows the user to select the reference motor (20).

Although the present disclosure has been described in detail above, the present disclosure is not limited to the individual embodiments described above. These embodiments include various additions, replacements, Modification, partial deletion, etc. are possible.

The motor monitoring device according to the present disclosure may be provided independently of the numerical control device that controls the machine tool, and may check the state of motors other than the spindle motor of the machine tool. As an example, the motor monitoring device according to the present disclosure may be a management computer that manages one or a plurality of numerical controllers with the functions of the motor monitoring section of the above-described embodiments added.

In the motor monitoring device according to the present disclosure, the notification section, stop command section, and override command section may be omitted. Also, the graph display section of the motor monitoring device according to the present disclosure may not have the reference setting section and the reference selection section.

1 machine tool 10 numerical controller (motor monitoring device)
11 program storage unit 12 motor control unit 13 motor monitoring unit 131 rotation speed acquisition unit 132 output value acquisition unit 133 divergence amount calculation unit 134 graph display unit 1341 graph area setting unit 1342 plot unit 1343 connection line drawing unit 1344 reference setting unit 1345 reference Selection unit 135 Notification unit 136 Stop command unit 137 Override command unit 20 Spindle motor 21 Revolution detector 22 Current detector 30 Display device 40 Input device

Claims (10)

a rotational speed acquisition unit that acquires rotational speeds of a plurality of motors;
an output value acquisition unit that acquires the output values of the plurality of motors;
a divergence calculation unit that calculates the divergence between the rotation speed and the output value between the motors;
a graph display unit for plotting a plurality of markers indicating a combination of the rotation speed and the output value for each motor in a graph area having the rotation speed on one axis and the output value on the other axis;
with
The graph display unit
dividing the graph area into a plurality of load zones with different load levels based on a plurality of time ratings of the motor for possible combinations of the rotation speed and the output value, and making the plurality of load zones identifiable; a graph area setting unit to be displayed;
a plotting unit that plots the plurality of markers in the graph area;
a connection line drawing unit that draws a connection line that connects the corresponding markers in different modes according to the amount of divergence;
A motor monitoring device comprising: 2. The motor monitoring device according to claim 1, wherein said plotting unit plots said markers in different manners for each of said corresponding motors. 2. The motor monitoring device according to claim 1 , wherein said connection line drawing unit draws connection lines in different manners depending on whether said divergence amount exceeds a predetermined divergence allowable amount. 2. The motor monitoring device according to claim 1 , wherein said connection line drawing unit draws connection lines in different manners according to the ratio between said deviation amount and a predetermined deviation allowable amount. 5. The motor monitoring device according to any one of claims 1 to 4, further comprising a notification unit that notifies when the deviation amount exceeds a predetermined notification deviation amount. 5. The motor monitoring device according to any one of claims 1 to 4 , further comprising a stop command section for stopping said motor when said deviation exceeds a predetermined stop deviation. 5. The motor monitoring device according to any one of claims 1 to 4 , further comprising an override command section that changes said rotation speed of said motor when said amount of deviation exceeds a predetermined amount of override deviation. 5. The motor monitoring device according to any one of claims 1 to 4 , wherein said connection line drawing unit draws said connection line between said marker of one of said motors serving as a reference and another said marker. 9. The motor monitoring according to claim 8, wherein said graph display unit further comprises a reference setting unit for setting said motor as said reference so that the number of other said motors whose deviation amount is within a predetermined range is maximized. Device. 9. The motor monitoring device according to claim 8 , wherein said graph display unit further has a reference selection unit that allows a user to select said motor as said reference.

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