Engine monitoring device

Abstract

A motor monitoring device according to an embodiment of the present disclosure, which makes it possible to easily determine the status of a motor, comprises: a speed detection unit which detects the speed of a motor operating according to an operating program; a history information storage unit which stores history information including the speed at fixed time intervals; and a chart display unit which graphically displays or plots markers indicating the speed in a chart area, wherein one axis is used for time and the other axis is used for speed, and wherein the chart display unit changes the mode of the marker according to a prescribed index.

Description

TECHNICAL FIELD

[0001] The present invention relates to an engine monitoring device. TECHNICAL BACKGROUND

[0002] For example, motors such as spindle motors used in machine tools, where the load can vary significantly, are at risk of overheating if a high-load condition persists and heat builds up. Different time ratings can be specified or set for such motors to ensure operation without overheating under specific conditions. For example, the time ratings specified in JIS-C4034-1 include continuous ratings that allow continuous operation, short-term ratings that allow operation for a certain period of time (load time) when operation starts at room temperature, and repetitive ratings that allow operation for a certain period of time (load time ratio) within a specified cycle time.

[0003] It has been proposed to estimate the time until a motor overheats while maintaining the current operating state (see, for example, Patent Document 1). Knowing the time until overheating can help determine whether the current machining operation can be completed. List of citationsPatent document

[0004] Patent Document 1: Japanese Patent No. 5628994 DISCLOSURE OF THE INVENTION Problems to be solved by the invention

[0005] However, simply estimating the time to overheating does not provide a straightforward understanding of the engine's operational reliability and margin. Specifically, when adjusting settings such as engine speed to maximize efficient processing while minimizing the overheating margin, it is not easy to determine how much the set values ​​should be increased or decreased. Therefore, a technique that allows for a straightforward understanding of the engine's condition is sought. Means to solve the problems

[0006] An engine monitoring device according to one aspect of the present disclosure includes: a rotation speed detection unit that detects a rotation speed of an engine operating according to an operation program; a history information storage unit that stores history information including the rotation speed at a regular time interval; and a chart display unit that plots a mark indicating the rotation speed on a chart area, one axis representing time and the other axis representing the rotation speed, the chart display unit changing a mode of the mark according to a predetermined index. Effects of the invention

[0007] According to the present disclosure, the condition of the engine can be easily understood. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a block diagram illustrating the configuration of a machine tool incorporating a motor monitoring device according to the first embodiment of the present disclosure; Fig. 2 is a table illustrating the information stored by the history information storage unit of the engine monitoring device of Fig. 1 stored information; and Fig. 3 is a diagram illustrating a control signal generated by the engine monitoring device of Fig. 1 displayed screen. PREFERRED MODE OF OPERATION FOR IMPLEMENTING THE INVENTION

[0008] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Fig. 1 is a block diagram illustrating the configuration of a machine tool 1 incorporating a motor monitoring device according to the first embodiment of the present disclosure.

[0009] The machine tool 1 includes a numerical control device 10 as an embodiment of the motor monitoring device according to the present invention, a spindle motor 20, a speed detector 21 that detects the speed of the spindle motor 20, a current detector 22 that detects the current of the spindle motor 20, a temperature detector 23 that detects the winding temperature of the spindle motor 20, a display device 30 that displays a screen according to the numerical control device 10, and an input device 40 that is used by the user for inputting to the numerical control device 10.

[0010] The numerical control device 10 controls the operation of the spindle motor 20 and other components according to an operation program (referred to as a machining program in numerical control devices) to enable the machine tool 1 to perform predetermined machining on the workpiece. The numerical control device 10 includes a memory, a processor (CPU), input / output interfaces, etc., and can be implemented by one or more computer devices executing appropriate control programs. Components of the numerical control device 10 described below are categorized based on the functions of the numerical control device 10 and may not be clearly distinguishable in terms of physical configuration and program configuration.

[0011] The spindle motor 20 is typically a motor that rotates a cutting tool or workpiece. The spindle motor 20 operates according to the operating program described above, but the load may fluctuate independently of the speed depending on the machining conditions. The speed detector 21, the current detector 22, and the temperature detector 23 may be composed of known sensors.

[0012] The display device 30 is a known display that displays according to signals input from the numerical control device 10. The display device 30 can be integrated with the numerical control device 10. The input device 40 is a device used by the user to input information into the numerical control device 10 and can be composed of known components such as a keyboard or mouse. The input device 40 can also be integrated with the numerical control device 10. The input device 40 can also be integrated with the display device 30. Specifically, the display device 30 and the input device 40 can be a single input / output device such as a touch panel.

[0013] In the present 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 axes of the machine tool 1, including the spindle motor 20; and a motor monitoring unit 13 that performs the functions of the motor monitoring device according to the present disclosure.

[0014] The program storage unit 11 stores operating programs executed by the machine tool 1. Each operating program includes a plurality of blocks that specify the unit operations of the machine tool 1. Each block includes one or more words formed by combinations of a plurality of characters (letters). Typically, each block is preceded by a sequence number to identify the block.

[0015] The motor control unit 12 executes the machining operations described in the operation program by controlling the spindle motor 20 and the motors of other drive axes of the machine tool 1 according to the operation program. The configuration of the motor control unit 12 is the same as that of known numerical control devices, so a detailed description is omitted.

[0016] The engine monitoring unit 13 includes a program acquisition unit 131, a rotational speed acquisition unit 132, an output value acquisition unit 133, an estimated time calculation unit 134, a history information storage unit 135, a chart display unit 136, a history information display unit 137, and a program display unit 138.

[0017] The program acquisition unit 131 acquires an operating program from the program storage unit 11 that specifies the operation to be monitored for the spindle motor 20. In other words, the program acquisition unit 131 loads the target operating program into the working memory.

[0018] The speed detection unit 132 detects the speed of the spindle motor 20 from the speed detector 21. The speed detection unit 132 can also detect the speed of the spindle motor 20 via the motor control unit 12.

[0019] The output value acquisition unit 133 acquires the output values ​​of the spindle motor 20, such as a current value, a power value, and a torque value. In the present embodiment, the output value acquisition unit 133 is configured to acquire the current value of the spindle motor 20 from the current detector 22 and use the power value calculated from the current value as the output value. However, the output value acquisition unit 133 may be configured to directly use the detected value, such as the current value, as the output value. The output value acquisition unit 133 may also acquire the output value or the values ​​necessary for calculating the output value from the motor control unit 12. The output value acquisition unit 133 may acquire two or more types of output values.

[0020] The estimated time calculation unit 134 calculates an estimated time until the overheating temperature is reached in a case where the rotational speed and the output value at that time are maintained by the spindle motor 20, based on the winding temperature of the spindle motor 20 detected by the temperature detector 23 and the current value or output value detected by the output value detection unit 133.

[0021] The history information storage unit 135 stores history information about the spindle motor 20 at regular intervals. The history information includes, as one element, the rotational speed of the spindle motor 20, and, as other elements, output values, winding temperature, load levels, other status information such as the estimated time until overheating of the spindle motor 20, program position information indicating the position of the corresponding command in the operating program, and modal information specifying the operation of the spindle motor 20. The program position information includes sequence numbers, line numbers, block numbers, etc.The modal information includes commands extracted from the operation program (not limited to those that directly specify the operation of the spindle motor 20, but also includes commands that can affect the operation of the spindle motor 20, such as a tool-specifying command) and setting values ​​of the numerical control device 10, such as the acceleration upper limit. Load levels can be determined by the relationship between the rotational speed and the output value on a two-axis graph. Specifically, the boundaries between the continuous rating, the time rating, and the maximum output on the graph can set the four load levels.define: the continuous operation level, which allows continuous operation, the short-term operation level, which allows intermittent operation within a predetermined period, the maximum load operation level, which allows operation in exceptional circumstances for a very short period, and a non-operation level, in which no operation at all is permitted, even for a very short period.

[0022] The time interval (unit time) for storing history information can be a predetermined fixed time or set according to user instructions via the input device 40. Excessively short time intervals make it impossible to confirm the correspondence to the operating program. Therefore, by allowing the user to specify the time interval for storing history information, convenient confirmation of the relationship between the operating state of the spindle motor 20 and the operating program is ensured. Fig. Figure 2 illustrates the details of the historical information stored by the historical information storage unit 135. As can be seen from the figure, the historical information storage unit 135 can be configured to create a relational database using the acquisition time or serial number of the data as the unique key for the historical information. The "-" in the figure indicates that the calculation is not possible or the corresponding information is not available.

[0023] As on the left side of Fig. As illustrated in Figure 3, the chart display unit 136 graphically displays markers indicating rotational speeds on a chart area, with one axis (vertical axis) representing time and the other axis (horizontal axis) representing rotational speed. The chart display unit 136 changes the mode of the markers according to a predetermined index. The indexes for determining the mode of the markers can use the state information of the spindle motor 20, such as the aforementioned load levels and the estimated time until the overheating temperature is reached. The mode of the markers is changed according to the state information such as load levels, allowing the user to easily understand the state of the spindle motor 20 at all times, for example, the safety margin.

[0024] Changes to the mode of the markers by the chart display unit 136 may include, for example, changing colors according to the value of the index (e.g., blue, yellow, red), changing the density or brightness according to the value of the index, and changing the length or size of the markers according to the value of the index. In other words, the chart display unit 136 preferably changes the display mode of the markers based on a predetermined rule to make the size of the index values ​​identifiable. The chart display unit 136 may independently change the plurality of display modes of the markers based on the plurality of indices to increase the amount of information presented to the user.

[0025] The chart display unit 136 can be configured to adjust the time span of the chart area based on user-specified times, the acceleration or deceleration completion times of the spindle motor 20, or the start and end times of the operating program. By appropriately adjusting the time span of the chart area, the user can easily understand the temporal changes in the state of the spindle motor 20.

[0026] The chart display unit 136 may allow the user to select the markers to be displayed to serve as triggers for displaying the program by the program display unit 138. As illustrated, the chart display unit 136 may omit markers when the speed is zero or when the load is considered very light based on some index, making the chart easier to read.

[0027] As on the left side of Fig.As illustrated in Figure 3, the history information display unit 137 displays at least part of the history information as text information aligned with the time axis of the chart display unit 136. In the illustrated example, the sequence number (Sequence No.) and the T-code (T-code) indicate only the updated information, and no description indicates that there are no changes from the previous time. The items displayed by the history information display unit 137 may be user-selectable from the history information.

[0028] The history information display unit 137 may allow the user to select history information to be displayed for each unit time to serve as a trigger for displaying the program by the program display unit 138.

[0029] The program display unit 138 editably displays a portion of the operation program corresponding to the markers selected by the user via the chart display unit 136 or the history information selected by the user via the history information display unit 137. In other words, the program display unit 138 provides an interface for partially rewriting the operation program stored in the program storage unit 11. The history information display unit 137 can display the program on the same screen as the chart display unit 136 and the history information display unit 137, or display the program on a larger area in a switched screen or pop-up display.

[0030] The numerical control device 10 according to the present embodiment includes the chart display unit 136, which plots marks indicating the rotational speed of the spindle motor 20 on a chart area, with one axis representing time and the other axis representing rotational speed, by changing the mode of the marks according to a predetermined index. This enables easy understanding of the relationship between the change in the rotational speed of the spindle motor 20 and the change in other states of the spindle motor 20.

[0031] Although the embodiments of the present disclosure have been described above, the present invention is not limited to the above-described embodiments. The effects described in the above embodiments are merely examples of the preferred effects resulting from the present invention, and the effects of the present invention are not limited to those described in the above embodiments.

[0032] The motor monitoring device according to the present disclosure can be provided independently of the numerical control device that controls the machine tool and can be used to monitor motors other than the spindle motor of the machine tool, such as the motor of a kneading machine. For example, the motor monitoring device according to the present disclosure can add the functions of the motor monitoring unit described in the above embodiments to a management computer that manages one or more numerical control devices, such as a control device for a kneading machine, or to a management computer that manages such a control device.

[0033] In the engine monitoring device according to the present disclosure, the history information display unit and the program display unit are optional configurations and may include a configuration for displaying history information or operation programs independently of the chart display unit. List of reference symbols 1 machine tool 10 numerical control or regulation device (engine monitoring device) 11 Program storage unit 12 Engine control or regulation unit 13 Engine monitoring unit 131 Program acquisition unit 132 Speed ​​detection unit 133 Output value acquisition unit 134 Estimation time calculation unit 135 History information storage unit 136 diagram display unit 137 History information display unit 138 Program display unit 20 spindle motor 21 Speed ​​detector 22 Current detector 23 Temperature detector 30 Display device 40 Input device QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] JP 5628994

[0004]

Claims

[1] Engine monitoring device comprising: a speed detection unit that detects a speed of an engine operating according to an operating program; a history information storage unit that stores history information including the rotational speed at a regular time interval; and a graph display unit that graphically displays or plots a mark indicating the speed on a graph area, one axis representing time and the other axis representing the speed, where the chart display unit changes a mode of the mark according to a predetermined index. [2] The engine monitoring device according to claim 1, wherein the history information storage unit sets the time interval according to a user instruction. [3] An engine monitoring device according to claim 1 or 2, further comprising: an output value acquisition unit that acquires an output value of the motor, wherein the chart display unit changes the mode of the marker according to a load level determined based on the speed and the output value. [4] The engine monitoring device according to any one of claims 1 to 3, wherein the chart display unit sets a time period of the chart area based on a user-specified time, an acceleration or deceleration completion time of the engine, or start and end times of the operation program. [5] Engine monitoring device according to one of claims 1 to 4, further comprising: a history information display unit that displays at least part of the history information as text information aligned with a time axis of the chart display unit. [6] The engine monitoring device of claim 5, further comprising: an estimated time calculation unit that calculates, as one piece of the history information, an estimated time until a superheat temperature is reached in a case where an operating state is maintained by the engine at that time. [7] Engine monitoring device according to claim 5 or 6, wherein the history information includes program position information that identifies a position in the operating program, and the engine monitoring device further comprises a program display unit that editably displays a portion of the operation program corresponding to the mark selected by a user via the chart display unit or corresponding to the history information selected by the user via the history information display unit.

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