JP7600857B2 - Bearing abnormality diagnosis device, abnormality diagnosis method, and program - Google Patents

Description

This invention relates to a bearing abnormality diagnosis device, an abnormality diagnosis method, and a program.

Conventionally, abnormality diagnosis is performed periodically on the bearings that make up various devices to prevent breakdowns and malfunctions. Abnormality diagnosis is performed by visual inspection, periodically disassembling the device containing the bearings. Meanwhile, in recent years, methods have been proposed for diagnosing abnormalities based on various signals obtained while the device is in operation, without disassembling the device, in order to reduce the cost and burden associated with visual inspection.

For example, Patent Document 1 describes a method for diagnosing rolling bearings in which frequency components are calculated using the synchronous average value of values obtained by a strain sensor, and damage is detected by comparing this value with a reference value. Patent Document 2 discloses a method for scoring the temperature of the bearing detected by a temperature sensor, and detecting bearing abnormalities by comparing this score with multiple threshold values. Patent Document 3 describes a method for diagnosing abnormalities in a bearing part provided in a drive unit, in which abnormalities in the bearing part are determined based on the rate of change at predetermined intervals of either the measured value or the control value of the tension or speed of the strip transported by the drive unit.

JP 2017-181267 A JP 2012-98253 A JP 2003-262570 A

In the configurations of the above-mentioned patent documents, cumulative values such as scores based on values detected by sensors or the like are used for abnormality diagnosis. Regarding the handling of the cumulative values, for example, if the cumulative values are not reset, there is a possibility that normal bearings will be judged as abnormal due to the accumulation of sporadically occurring noise data. In addition, if the cumulative values are periodically reset at a predetermined time interval, there is a possibility that abnormal bearings will be treated as normal because the cumulative value fails to reach a threshold value within that interval.

For example, in Patent Document 1, the accumulation conditions for the accumulated value and the accumulation stop conditions are not taken into consideration. Therefore, as a result of repeated false detection of an abnormality due to noise, etc., there is a possibility that a false alarm will be issued due to the repeated accumulated value. Furthermore, in Patent Documents 2 and 3, the accumulated value is periodically erased. In such a configuration, for example, if the frequency of abnormality diagnosis (detection of abnormality occurrence) is low, the accumulated value will be reset before it reaches the threshold value, and there will be cases where an abnormality cannot be detected and notified.

In consideration of the above problems, the present invention aims to make it possible to simultaneously prevent erroneous alarms due to the accumulation of misdiagnoses and prevent abnormalities from being overlooked by resetting the accumulated value when diagnosing bearing abnormalities using the accumulated value.

In order to solve the above problems, the present invention has the following configuration. That is, a bearing abnormality diagnosis device is provided with a sensor that acquires state information of the bearing, and a diagnosis means that diagnoses whether an abnormality has occurred in the bearing by comparing an accumulated result of an evaluation value based on the state information acquired by the sensor with a predetermined threshold value, and the diagnosis means subtracts the accumulated result at regular intervals based on predetermined conditions.

Another aspect of the present invention has the following configuration. That is, it is a bearing abnormality diagnosis method, which includes an acquisition step of acquiring state information of the bearing, and a diagnosis step of diagnosing whether or not an abnormality has occurred in the bearing by comparing an accumulated result of an evaluation value based on the state information with a predetermined threshold, and in the diagnosis step, the accumulated result is subtracted at regular intervals based on a predetermined condition.

Another aspect of the present invention has the following configuration: a program that causes a computer to execute an acquisition step of acquiring bearing status information, and a diagnosis step of diagnosing whether an abnormality has occurred in the bearing by comparing an accumulated result of evaluation values based on the status information with a predetermined threshold, and in the diagnosis step, the accumulated result is subtracted at regular intervals based on predetermined conditions.

The present invention makes it possible to simultaneously prevent false alarms caused by the accumulation of misdiagnoses and prevent abnormalities from being overlooked by resetting the accumulated values when diagnosing bearings using accumulated values.

FIG. 1 is a diagram showing an example of the overall configuration of a system according to a first embodiment. 4 is a flowchart of a process for abnormality diagnosis according to the first embodiment. 11A and 11B are diagrams for explaining changes in a cumulative counter when comparing the method according to the present invention with a conventional method; FIG. 11 is a diagram showing the relationship between a detection value and an evaluation value according to the second embodiment. 10 is a flowchart of a process for abnormality diagnosis according to a second embodiment. FIG. 1 is a diagram showing an example of the overall configuration of a system according to an embodiment of the present invention. FIG. 1 is a diagram showing an example of the overall configuration of a system according to an embodiment of the present invention.

The following describes the embodiment of the present invention with reference to the drawings. Note that the embodiment described below is one embodiment for explaining the present invention, and is not intended to be interpreted as limiting the present invention, and not all of the configurations described in each embodiment are necessarily essential configurations for solving the problems of the present invention. In addition, in each drawing, the same components are given the same reference numbers to indicate their correspondence.

First Embodiment
A first embodiment of the present invention will be described below. The device or machine in which the bearing according to the present invention is provided is not particularly limited. The type of bearing is also not particularly limited, and the present invention may be applied to various types of bearings, such as ball bearings, thrust bearings, and spherical roller bearings.

[Overall configuration]
1 is a diagram showing an example of the overall configuration of a bearing abnormality diagnosis device (hereinafter simply referred to as the "diagnosis device") according to this embodiment. In this embodiment, a bearing 3 to be diagnosed and a diagnosis device 1 are configured separately, and the diagnosis device 1 obtains state information of the bearing 3 by a sensor 2 and performs abnormality diagnosis.

The sensor 2 acquires status information of the bearing 3. In this embodiment, the sensor 2 uses a vibration sensor and detects vibrations caused by the operation of the bearing 3 as status information. The vibration sensor may be configured, for example, with an acceleration sensor. It is desirable to install the sensor 2 near the bearing 3 in order to improve the accuracy in detecting the status of the bearing 3. The distance and positional relationship between the bearing 3 and the sensor 2 here may be determined according to the structure of the bearing 3, the function of the sensor 2, etc.

In FIG. 1, only one sensor 2 is shown, but this configuration is not limited to this. For example, multiple sensors may be provided depending on the size and configuration of the bearing 3 to be diagnosed. In this case, for example, the values detected by the multiple sensors 2 may be averaged to improve detection accuracy and reduce noise.

The diagnostic device 1 includes a status information acquisition unit 11, a status information management unit 12, a diagnostic processing unit 13, a diagnostic result storage unit 14, a timer unit 15, and an alarm processing unit 16. The status information acquisition unit 11 acquires status information (here, vibration information) detected by the sensor 2 and generated when the bearing 3 is in operation. The status information management unit 12 manages the status information acquired by the status information acquisition unit 11. In addition, the status information management unit 12 converts the status information acquired by the status information acquisition unit 11 into a format used in the diagnostic processing.

The diagnostic processing unit 13 executes the diagnostic processing according to this embodiment. Details of the diagnostic processing according to this embodiment will be described later with reference to FIG. 2. The diagnostic result storage unit 14 stores various information related to the diagnostic results by the diagnostic processing unit 13 and the progress of the diagnostic processing. The timing unit 15 measures the time during the diagnostic processing by the diagnostic processing unit 13. The notification processing unit 16 performs notification processing of the results of the diagnostic processing. The notification method of the notification processing unit 16 is not particularly limited, and may be a visual notification method such as screen output, or an auditory notification method such as audio output.

[Processing flow]
Fig. 2 is a flowchart showing a diagnostic process by the diagnostic device 1 according to this embodiment. This process may be realized, for example, by a processing unit such as a CPU (Central Processing Unit) included in the diagnostic device 1 reading out a program for implementing each part shown in Fig. 1 from a storage unit such as a HDD (Hard Disk Drive) or ROM (Read Only Memory) and executing the program. Furthermore, when this process is started, the sensor 2 is installed at a predetermined position in the vicinity of the bearing 3 to be diagnosed, and the diagnostic device 1 is in a state in which it is possible to obtain state information (here, vibration information) of the bearing 3 from the sensor 2.

At S201, the diagnostic device 1 initializes the values of a timer and an abnormality counter configured in a memory unit (not shown) such as a RAM (Random Access Memory) provided in the diagnostic device 1.

At S202, the diagnostic device 1 starts timing using the timing unit 15. In this embodiment, the time is measured by counting using a timer.

In S203, the diagnostic device 1 acquires status information of the bearing 3 to be diagnosed via the sensor 2. Here, vibration information is acquired as the status information. The vibration information may be vibration information at a predefined time interval or number of rotations of the bearing 3. Furthermore, the vibration information may be configured to calculate and use an effective value, average value, or moving average value per any unit time from the input signal (vibration information) from the sensor 2 in order to suppress the effects of electrical and mechanical noise, for example.

In S204, the diagnostic device 1 converts the status information acquired in S203 into a value for determining an abnormal state (hereinafter referred to as an "evaluation value") based on a predetermined conversion rule. One example of the predetermined conversion rule here is to calculate a moving average value over a predetermined period of time for the frequency components indicated by the vibration information, which is the status information. Alternatively, noise may be reduced by applying an LPF (Low Pass Filter) to the vibration information to remove high frequency components. Alternatively, the value of the vibration information may be converted into an evaluation value using a conversion table such as a predefined LUT (Look Up Table).

In S205, the diagnostic device 1 compares the evaluation value converted in S204 with a predefined threshold value. Here, if the evaluation value is equal to or greater than the threshold value, it means that the evaluation value indicates an abnormal value. The threshold value is predefined corresponding to the bearing 3 to be diagnosed, and is stored and managed in a storage unit (not shown). If the evaluation value indicates an abnormal value (YES in S205), the process of the diagnostic device 1 proceeds to S206. On the other hand, if the evaluation value does not indicate an abnormal value, i.e., if the evaluation value is smaller than the threshold value (NO in S205), the process of the diagnostic device 1 proceeds to S207.

In S206, the diagnostic device 1 increments the abnormality counter by 1. After that, the processing of the diagnostic device 1 proceeds to S207.

In S207, the diagnostic device 1 determines whether the abnormality counter value is equal to or greater than a predetermined threshold value. The predetermined threshold value here is predefined and stored in a memory unit (not shown). Note that the threshold value used in the processing of S205 is different from the threshold value used in the processing of S207. If the abnormality counter value is equal to or greater than the threshold value (YES in S207), the processing of the diagnostic device 1 proceeds to S210. On the other hand, if the abnormality counter value is less than the threshold value (NO in S207), the processing of the diagnostic device 1 proceeds to S208.

In S208, the diagnostic device 1 refers to the timer value and determines whether it has exceeded a certain value. In other words, the diagnostic device 1 determines whether a certain amount of time has passed since the timer was last initialized. The certain amount of time here is predefined and stored in a memory unit (not shown), and may be, for example, 24 hours (one day). If the certain amount of time has passed (YES in S208), the processing of the diagnostic device 1 proceeds to S209. On the other hand, if the certain amount of time has not passed (NO in S208), the processing of the diagnostic device 1 proceeds to S212.

In S209, the diagnostic device 1 subtracts the abnormality counter value based on a predetermined rule. The predetermined rule here may be, for example, multiplying the abnormality counter value by a predetermined ratio R1 (0<R1<1). Alternatively, the abnormality counter value may be subtracted by subtracting a predetermined value A1 (0<A1). The predetermined rule is assumed to be defined in advance and stored in a memory unit (not shown). After that, the processing of the diagnostic device 1 proceeds to S211.

In S210, the diagnostic device 1 notifies a predetermined notification destination that an abnormality has occurred in the bearing 3 to be diagnosed. The notification method here is not particularly limited, but for example, a screen notifying the abnormality may be displayed on a display device (not shown) provided in the diagnostic device 1, or a signal indicating the abnormality may be sent to a predetermined destination. In addition, the user of the diagnostic device 1 may be configured to be able to select any one of a number of notification methods. After that, the processing of the diagnostic device 1 proceeds to S211.

In S211, the diagnostic device 1 initializes the timer value. After that, the processing of the diagnostic device 1 proceeds to S212.

In S212, the diagnostic device 1 determines whether to continue the diagnosis. The decision to continue the diagnosis may be made based on an instruction from a user of the diagnostic device 1. Alternatively, the number of times and contents of abnormality notifications may be managed as a notification history, and the decision to continue the diagnosis may be made based on the notification history. If it is determined that the diagnosis should be continued (YES in S212), the process of the diagnostic device 1 proceeds to S214. On the other hand, if it is determined that the diagnosis should not be continued (NO in S212), the process of the diagnostic device 1 proceeds to S213.

In S213, the diagnostic device 1 stops the timing operation that started in S202. Then, this processing flow ends.

In S214, the diagnostic device 1 waits for a predetermined time. The wait time here is predefined depending on the processing load and accuracy of the diagnosis, and is managed in a storage unit (not shown). The wait time here corresponds to the diagnosis interval, and may be, for example, several tens of seconds. Note that the interval for subtracting the value of the abnormality counter (corresponding to the fixed time used in the processing of S208) and the diagnosis interval (corresponding to the wait time of S214) may be configured to be switched depending on the operating conditions of the bearing 3. Thereafter, the processing of the diagnostic device 1 returns to the processing of S203, and the subsequent processing is repeated.

In the above process, a configuration in which a threshold value of 1 is set for the abnormality counter is shown, but the present invention is not limited to this configuration. For example, a configuration in which multiple threshold values are set corresponding to the urgency of the abnormality (or the degree of occurrence of the abnormality), and the urgency of the abnormality is determined by comparing the threshold values with the abnormality counter value may be used. In this case, the content of the notification may be switched depending on the urgency obtained as a result of the diagnosis.

[Example of abnormality counter fluctuation]
FIG. 3 is a diagram for explaining the variation of the abnormality counter used when performing the abnormality diagnosis according to the present embodiment. In addition, for comparison, the variation of the abnormality counter (accumulated value related to the abnormality diagnosis) in the conventional method is also explained. As the conventional method, a method in which the abnormality counter is not reset and a method in which the abnormality counter is periodically reset are given as examples. In the diagnosis method according to the present embodiment, the value of the abnormality counter is subtracted based on a predetermined rule. The horizontal axis of each graph shown in FIG. 3 indicates the passage of time, and the vertical axis indicates the value of the abnormality counter. In addition, the dashed line shown in FIG. 3 is a threshold value for notification set for the abnormality counter, and corresponds to the threshold value used in the judgment process of S207 in FIG. 2.

3, the upper part shows the variation of the abnormality counter when an abnormality occurs in the bearing 3. On the other hand, the lower part shows the variation of the abnormality counter when no abnormality occurs in the bearing 3. Figures 3(a) and 3(b) have different axis scales. Figure 3(a) shows an example of a case where it is determined whether or not to notify an abnormality based on the results of a small number of abnormality diagnoses. In Figure 3(a), one step corresponds to 1 on the abnormality counter. Accordingly, the threshold value for the abnormality counter is set low, and for example, a value of several tens is used as the threshold value. Figure 3(b) shows an example of a case where it is determined whether or not to notify an abnormality based on the results of a relatively large number of abnormality diagnoses. In Figure 3(b), the horizontal axis scale is different from that in Figure 3(a), so the transition of the abnormality counter value is shown as a slope. This corresponds to a case where the diagnosis period is longer in Figure 3(b) (i.e., the number of abnormality diagnoses is large), and the threshold value for the abnormality counter is also set high. For example, a value of several hundreds to several thousands is used as the threshold value.

In the conventional method of not resetting the abnormality counter, if there is an abnormality in the bearing 3, the abnormality counter counts and reaches the threshold for notification, causing an abnormality notification (see the upper center of Figures 3(a) and 3(b)). On the other hand, even if no abnormality is occurring in the bearing 3, repeated false detection of an abnormality can cause the value of the abnormality counter to reach the threshold for notification, resulting in a false notification (see the lower center of Figures 3(a) and 3(b)). In other words, with the method of not resetting the abnormality counter, false notifications can occur due to the accumulation of false detections.

In the conventional method of periodically resetting the abnormality counter, if there is no abnormality in the bearing 3, the abnormality counter is periodically reset, so that even if an abnormality is falsely detected, the threshold for notification is prevented from being reached, and the occurrence of false notifications is prevented (see the lower right of Figures 3(a) and 3(b)). On the other hand, if an abnormality occurs in the bearing 3, and the abnormality counter is reset just before the value of the abnormality counter reaches the threshold due to the timing of the detection of the abnormality, the abnormality cannot be notified (see the upper right of Figures 3(a) and 3(b)). As a result, the abnormality may be overlooked, that is, an abnormality may not be notified even if it occurs.

In the method according to the present embodiment, when there is an abnormality in the bearing 3, counting and subtraction of the abnormality counter are repeated, so that the value of the abnormality counter exceeds the threshold for notification (see the upper left of FIG. 3(a) and FIG. 3(b)). At this time, a predetermined rule is set so that the increase rate (increase frequency) of the abnormality counter due to the determination that there is an abnormality is greater than the decrease rate (decrease frequency) of the abnormality counter due to the subtraction process (corresponding to S209 in FIG. 2). As a result, the abnormality is notified. On the other hand, when there is no abnormality in the bearing 3, a predetermined rule is configured so that the decrease rate (decrease frequency) of the abnormality counter due to the subtraction process (corresponding to S209 in FIG. 2) is greater than the increase rate (increase frequency) of the abnormality counter due to the determination that there is an abnormality. Therefore, when there is no abnormality in the bearing 3, the value of the abnormality counter is suppressed from reaching the threshold for notification (see the lower left of FIG. 3(a) and FIG. 3(b)). Therefore, in the present embodiment, it is possible to appropriately handle the abnormality counter without the inconveniences of the conventional method. This makes it possible to prevent false alarms about bearing abnormalities and to prevent abnormalities from going unnoticed.

As described above, this embodiment makes it possible to perform an appropriate diagnosis when diagnosing bearing abnormalities using accumulated values. More specifically, when diagnosing bearings using accumulated values, it is possible to simultaneously suppress false alarms due to the accumulation of misdiagnoses and suppress overlooking abnormalities by resetting the accumulated values.

Second Embodiment
In the first embodiment, a configuration in which vibration information is used as the status information acquired from the bearing 3 is described. In the second embodiment of the present invention, a configuration in which temperature information is used as the status information acquired from the bearing 3 is described. Note that a description of configurations that overlap with the first embodiment will be omitted, and the description will focus on the differences. The system configuration according to this embodiment is largely similar to the configuration of FIG. 1 described in the first embodiment, with the difference being that the sensor 2 is replaced from a vibration sensor to a temperature sensor.

Figure 4 shows the relationship between the temperature information of the bearing 3 according to this embodiment and the score assigned to that temperature information. The score assigned here is used as an evaluation value when diagnosing an abnormality. Figure 4(a) shows the relationship between the absolute temperature [°C] of the bearing 3 and the relative temperature difference [°C]. In this embodiment, a reference value for the temperature when the bearing 3 is operating normally is set, and the difference between that reference value and the current absolute temperature is taken as the relative temperature difference. Note that the reference value for determining the difference from the current absolute temperature is not limited to a predefined value, and may be calculated based on the detected temperature from other bearings operating under similar environmental conditions. For example, the absolute temperatures of multiple other bearings may be obtained, and the reference temperature may be derived from the average value.

Figure 4 (b) shows the evaluation value for the rate of temperature rise [°C/min] of bearing 3 over a certain time period (here, in units of one minute). The unit time here is an example, and other units may be used. Also, the scores shown in Figure 4 are an example, and other values may be used.

[Processing flow]
Fig. 5 is a flowchart showing diagnostic processing by the diagnostic device 1 according to this embodiment. This processing may be realized, for example, by a processing unit (not shown) such as a CPU provided in the diagnostic device 1 reading out a program for implementing each part shown in Fig. 1 from a storage unit (not shown) such as a HDD or ROM and executing it. Furthermore, when this processing is started, the sensor 2 is installed at a predetermined position in the vicinity of the bearing 3 to be diagnosed, and the diagnostic device 1 is in a state in which it is possible to obtain state information (here, temperature information) of the bearing 3 from the sensor 2.

At S501, the diagnostic device 1 initializes a timer and an accumulated value configured in a memory unit (not shown) such as a RAM provided in the diagnostic device 1.

At S502, the diagnostic device 1 starts timing using the timing unit 15. In this embodiment, the time is measured by counting using a timer.

In S503, the diagnostic device 1 acquires status information of the bearing 3 to be diagnosed via the sensor 2. Here, temperature information is acquired as the status information. The temperature information also includes the absolute temperature of the bearing 3 and information on the temperature change per a predetermined unit time.

In S504, the diagnostic device 1 derives a score for the temperature information based on the state information acquired in S503 and the table shown in FIG. 4. Note that the table shown in FIG. 4 is predefined and stored in a storage unit (not shown).

In S505, the diagnostic device 1 adds the score derived in S504 to the cumulative value.

In S506, the diagnostic device 1 determines whether the current cumulative value is equal to or greater than a predetermined threshold value. The predetermined threshold value here is assumed to be predefined and stored in a memory unit (not shown). If the cumulative value is equal to or greater than the threshold value (YES in S506), the processing of the diagnostic device 1 proceeds to S509. On the other hand, if the cumulative value is less than the threshold value (NO in S506), the processing of the diagnostic device 1 proceeds to S507.

In S507, the diagnostic device 1 refers to the timer value and determines whether it has exceeded a certain value. In other words, the diagnostic device 1 determines whether a certain amount of time has passed since the timer was last initialized. The certain amount of time here is predefined and stored in a memory unit (not shown), and may be, for example, 24 hours (one day). If the certain amount of time has passed (YES in S507), the processing of the diagnostic device 1 proceeds to S508. On the other hand, if the certain amount of time has not passed (NO in S507), the processing of the diagnostic device 1 proceeds to S511.

In S508, the diagnostic device 1 subtracts the accumulated value based on a predetermined rule. The predetermined rule here may be, for example, multiplying the accumulated value by a predetermined ratio R2 (0<R2<1). Alternatively, the cumulative value may be subtracted by subtracting a predetermined value A2 (0<R2). The predetermined rule is assumed to be defined in advance and stored in a memory unit (not shown). After that, the processing of the diagnostic device 1 proceeds to S510.

In S509, the diagnostic device 1 notifies a predetermined notification destination that an abnormality has occurred in the bearing 3 to be diagnosed. The notification method here is not particularly limited, but for example, a screen notifying the abnormality may be displayed on a display device (not shown) provided in the diagnostic device 1, or a signal indicating the abnormality may be sent to a predetermined destination. In addition, the user of the diagnostic device 1 may be configured to be able to select any one of a number of notification methods. After that, the processing of the diagnostic device 1 proceeds to S510.

At S510, the diagnostic device 1 initializes the timer value. After that, the processing of the diagnostic device 1 proceeds to S511.

In S511, the diagnostic device 1 determines whether to continue the diagnosis. The decision to continue the diagnosis may be made based on an instruction from a user of the diagnostic device 1. Alternatively, the number of times and contents of abnormality notifications may be managed as a notification history, and the decision to continue the diagnosis may be made based on the notification history. If it is determined that the diagnosis should be continued (YES in S511), the processing of the diagnostic device 1 proceeds to S513. On the other hand, if it is determined that the diagnosis should not be continued (NO in S511), the processing of the diagnostic device 1 proceeds to S512.

At S512, the diagnostic device 1 stops the timing operation that started at S502. Then, this processing flow ends.

In S513, the diagnostic device 1 waits for a predetermined time. The wait time here is predetermined depending on the processing load and accuracy of the diagnosis, and is managed in a storage unit (not shown). The wait time here corresponds to the diagnosis interval, and may be, for example, several tens of seconds. Note that the interval for subtracting the value of the abnormality counter (corresponding to the fixed time used in the processing of S507) and the diagnosis interval (corresponding to the wait time of S513) may be configured to be switched depending on the operating conditions of the bearing 3. Thereafter, the processing of the diagnostic device 1 returns to the processing of S503, and the subsequent processing is repeated.

In the above process, a configuration in which a threshold value of 1 is set for the cumulative value is shown, but the present invention is not limited to this configuration. For example, a configuration in which multiple threshold values are set corresponding to the urgency (degree) of the abnormality, and the urgency of the abnormality is determined by comparing the threshold values with the cumulative value may be used. In this case, the content of the notification may be switched depending on the urgency obtained as a result of the diagnosis.

As described above, this embodiment makes it possible to perform an appropriate diagnosis when diagnosing bearing abnormalities using accumulated values. More specifically, when diagnosing bearings using accumulated values, it is possible to simultaneously suppress false alarms due to the accumulation of misdiagnoses and suppress overlooking abnormalities by resetting the accumulated values.

<Other embodiments>
In the above embodiment, the diagnosis device 1 and the sensor 2 are configured separately from the bearing 3. The present invention is not limited to the above configuration. For example, as shown in Fig. 6, a configuration may be adopted in which a drive device 60 including a bearing 3 and the diagnosis device 1 are communicatively connected via a network 62.

Figure 6 is a diagram showing an example of the overall configuration of an embodiment of a system to which the present invention can be applied. In this embodiment, a drive unit 60 and a diagnostic unit 50 are communicatively connected via a network 62. There are no particular limitations on the communication method or communication standard in the network 62, and multiple networks may be combined.

The drive device 60 includes a sensor 2, a bearing 3, and a communication control unit 61. The communication control unit 61 is a processing unit that controls communication processing with the outside, and transmits various information detected by the sensor 2 to the outside (here, the diagnostic device 1).

The diagnostic device 1 includes a communication control unit 63, a status information management unit 12, a diagnostic processing unit 13, a diagnostic result storage unit 14, a timer unit 15, and a notification processing unit 16. The communication control unit 63 is a processing unit that controls communication processing with the outside, and acquires various information transmitted from the drive device 60 via a network 62. The rest of the configuration is the same as the configuration shown in FIG. 1 in the first embodiment.

The present invention can also be applied to a bearing unit 70 that includes a sensor 2 and a bearing 3, as shown in FIG. 7.

As with the above embodiment, it is possible to diagnose bearing abnormalities with the configurations shown in Figures 6 and 7.

In the above embodiment, a configuration has been shown in which the status information of a component is detected by a vibration sensor or a temperature sensor, and the component is diagnosed using the status information, but the configuration is not limited to this. For example, a sound sensor (microphone) may be used as the status sensor that acquires the status information of the component. In this case, the diagnosis is performed using the sound (noise) information detected by the sound sensor. The type and configuration of the status sensor are not particularly limited, and other types of sensors may be used depending on the component. Furthermore, multiple types of sensors may be combined depending on the type and structure of the component to be diagnosed, and the detection results of each sensor may be combined to perform the diagnosis.

In the above embodiment, an example was shown in which an abnormality counter was used when a vibration sensor was used (first embodiment), and a score was used when a temperature sensor was used (second embodiment). However, this configuration is not limited to this, and the combination of the sensor type and the method of accumulating the evaluation value (score, counter, etc.) may be changed arbitrarily.

The present invention can also be realized by providing a program or application for implementing the functions of one or more of the above-described embodiments to a system or device via a network or storage medium, and having one or more processors in the computer of the system or device read and execute the program.

It may also be realized by a circuit that realizes one or more functions (for example, an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array)).

The present invention is not limited to the above-described embodiment, and it is intended that the various components of the embodiment may be combined with each other, and that those skilled in the art may modify and apply the invention based on the description in the specification and well-known technology, and this is included in the scope of the protection sought.

As described above, the present specification discloses the following:
(1) A bearing abnormality diagnosis device, comprising:
A sensor for acquiring status information of the bearing;
a diagnostic means for diagnosing whether or not an abnormality has occurred in the bearing by comparing an accumulation result of an evaluation value based on the state information acquired by the sensor with a predetermined threshold value,
The abnormality diagnosis device according to claim 1, wherein the diagnosis means subtracts from the accumulated result at regular intervals based on a predetermined condition.
According to this configuration, when diagnosing a bearing abnormality using the accumulated value, it is possible to perform an appropriate diagnosis. More specifically, when diagnosing a bearing abnormality using the accumulated value, it is possible to simultaneously suppress erroneous reporting due to the accumulation of erroneous diagnoses and suppress overlooking an abnormality by resetting the accumulated value.

(2) The abnormality diagnosis device according to (1), wherein the predetermined condition is to subtract a certain percentage or a certain value from the cumulative result.
According to this configuration, by subtracting a fixed ratio or a fixed value from the accumulated result at fixed time intervals, it becomes possible to appropriately diagnose an abnormality in the bearing.

(3) The abnormality diagnosis device according to (1) or (2), further comprising a notification means for notifying the user that an abnormality has occurred in the bearing when the accumulated result value exceeds the predetermined threshold value.
According to this configuration, when diagnosing a bearing using the accumulated value, it is possible to appropriately notify an abnormality in accordance with the accumulated value that is subtracted based on a predetermined condition.

(4) The abnormality diagnosis device according to any one of (1) to (3), wherein the diagnosis means converts the status information acquired by the sensor into an evaluation value using a predefined table and accumulates the evaluation value.
This configuration makes it easy to convert the state information into an evaluation value used in diagnosis.

(5) The abnormality diagnosis device according to any one of (1) to (3), wherein the diagnosis means performs accumulation using a counter that counts when the status information acquired by the sensor is equal to or greater than a predetermined threshold value.
This configuration facilitates diagnosis processing based on the state information.

(6) The abnormality diagnosis device according to any one of (1) to (5), wherein the sensor is a vibration sensor.
According to this configuration, it is possible to diagnose an abnormality in the bearing based on the vibration information obtained from the vibration sensor.

(7) The abnormality diagnosis device according to any one of (1) to (5), wherein the sensor is a temperature sensor.
According to this configuration, it is possible to diagnose an abnormality in the bearing based on the temperature information obtained from the temperature sensor.

(8) The predetermined threshold value is set to a plurality of values according to the degree of abnormality,
The abnormality diagnosis device according to any one of (1) to (7), wherein the diagnosis means diagnoses the degree of abnormality of the bearing by comparing each of the plurality of values with the cumulative result.
This configuration makes it possible to diagnose an abnormality in the bearing according to the degree of the abnormality.

(9) A method for diagnosing an abnormality in a bearing, comprising:
an acquisition step of acquiring status information of the bearing;
a diagnosis step of diagnosing whether or not an abnormality has occurred in the bearing by comparing an accumulation result of the evaluation value based on the state information with a predetermined threshold value,
The abnormality diagnosis method, wherein in the diagnosis step, the cumulative result is subtracted at regular time intervals based on a predetermined condition.
According to this configuration, when diagnosing a bearing abnormality using the accumulated value, it is possible to perform an appropriate diagnosis. More specifically, when diagnosing a bearing abnormality using the accumulated value, it is possible to simultaneously suppress erroneous reporting due to the accumulation of erroneous diagnoses and suppress overlooking an abnormality by resetting the accumulated value.

(10) A computer is provided with:
An acquisition step of acquiring bearing status information;
a diagnosis step of diagnosing whether or not an abnormality has occurred in the bearing by comparing an accumulation result of the evaluation value based on the state information with a predetermined threshold value;
The program, wherein in the diagnosis step, the cumulative result is subtracted at regular time intervals based on a predetermined condition.
According to this configuration, when diagnosing a bearing abnormality using the accumulated value, it is possible to perform an appropriate diagnosis. More specifically, when diagnosing a bearing abnormality using the accumulated value, it is possible to simultaneously suppress erroneous reporting due to the accumulation of erroneous diagnoses and suppress overlooking an abnormality by resetting the accumulated value.

REFERENCE SIGNS LIST 1... diagnostic device 2... sensor 3... bearing 11... status information acquisition section 12... status information management section 13... diagnostic processing section 14... diagnostic result storage section 15... timing section 16... notification processing section 60... drive devices 61, 63... communication control section 62... network 70... bearing unit

Claims (9)

A bearing abnormality diagnosis device,
A sensor for acquiring status information of the bearing;
a diagnostic means for diagnosing whether or not an abnormality has occurred in the bearing by comparing an accumulation result of an evaluation value based on the state information acquired by the sensor with a predetermined threshold value,
The diagnostic means subtracts from the cumulative result at regular intervals based on a predetermined condition ,
The diagnostic means performs accumulation using a counter that counts when the state information acquired by the sensor is equal to or greater than a predetermined threshold value,
the predetermined condition is set so that, when there is an abnormality in the bearing, an increase rate of the counter that is counted when the acquired status information is equal to or greater than a predefined threshold value is greater than a decrease rate of the counter due to the subtraction;
the predetermined condition is set such that, when there is no abnormality in the bearing, a decrement rate of the counter due to the subtraction is greater than an increment rate of the counter counted when the acquired status information is equal to or greater than a predefined threshold value.
An abnormality diagnosis device comprising: The abnormality diagnosis device according to claim 1, characterized in that the predetermined condition is to subtract a certain percentage or a certain value from the cumulative result. The abnormality diagnosis device according to claim 1 or 2, further comprising a notification means for notifying the user that an abnormality has occurred in the bearing when the accumulated result value exceeds the predetermined threshold value. The abnormality diagnosis device according to any one of claims 1 to 3, characterized in that the diagnosis means converts the status information acquired by the sensor into an evaluation value using a predefined table and accumulates it. 5. The abnormality diagnosis device according to claim 1 , wherein the sensor is a vibration sensor. 5. The abnormality diagnosis device according to claim 1 , wherein the sensor is a temperature sensor. The predetermined threshold value is set to a plurality of values according to the degree of abnormality,
7. The abnormality diagnosis device according to claim 1 , wherein the diagnosis means diagnoses the degree of abnormality of the bearing by comparing each of the plurality of values with the cumulative result. A bearing abnormality diagnosis method, comprising:
an acquisition step of acquiring status information of the bearing;
a diagnosis step of diagnosing whether or not an abnormality has occurred in the bearing by comparing an accumulation result of the evaluation value based on the state information with a predetermined threshold value,
In the diagnosis step, the cumulative result is subtracted at regular time intervals based on a predetermined condition ,
In the diagnosis step, accumulation is performed using a counter that counts when the acquired status information is equal to or greater than a predetermined threshold value;
the predetermined condition is set so that, when there is an abnormality in the bearing, an increase rate of the counter that is counted when the acquired status information is equal to or greater than a predefined threshold value is greater than a decrease rate of the counter due to the subtraction;
the predetermined condition is set such that, when there is no abnormality in the bearing, a decrement rate of the counter due to the subtraction is greater than an increment rate of the counter counted when the acquired status information is equal to or greater than a predefined threshold value.
13. An abnormality diagnosis method comprising: On the computer,
An acquisition step of acquiring bearing status information;
a diagnosis step of diagnosing whether or not an abnormality has occurred in the bearing by comparing an accumulation result of the evaluation value based on the state information with a predetermined threshold value;
In the diagnosis step, the cumulative result is subtracted at regular time intervals based on a predetermined condition ,
In the diagnosis step, accumulation is performed using a counter that counts when the acquired status information is equal to or greater than a predetermined threshold value;
the predetermined condition is set so that, when there is an abnormality in the bearing, an increase rate of the counter that is counted when the acquired status information is equal to or greater than a predefined threshold value is greater than a decrease rate of the counter due to the subtraction;
the predetermined condition is set such that, when there is no abnormality in the bearing, a decrement rate of the counter due to the subtraction is greater than an increment rate of the counter counted when the acquired status information is equal to or greater than a predefined threshold value.
A program characterized by:

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