JP7695901B2 - Shaft coupling diagnostic device and shaft coupling diagnostic method - Google Patents

Description

The present invention relates to a shaft coupling diagnostic device and a shaft coupling diagnostic method.

Construction machinery is equipped with a shaft coupling that connects a drive shaft (e.g., the output shaft of an engine) that outputs the power of a prime mover (e.g., an engine) to a driven shaft (e.g., the rotating shaft of a hydraulic pump) of a driven mover (e.g., a hydraulic pump) that is driven by the power transmitted from the drive shaft of the prime mover.

Many of the shaft couplings installed on construction machinery are shaft couplings that transmit the power output from the drive shaft of the prime mover to the driven shaft of the driven machine via an elastic body (also called "elastic shaft couplings"). This type of shaft coupling can absorb misalignment between the central axis of the drive shaft and the central axis of the driven shaft, as well as torque fluctuations in the prime mover, by elastic deformation of the elastic body, allowing for smooth torque transmission between the prime mover and the driven machine.

In shaft couplings, the elastic body wears out due to aging and deformation caused by fatigue. When the elastic body wears out, it becomes difficult to transmit torque smoothly between the prime mover and the driven machine, and in some cases, failures such as shaft breakage may occur. Therefore, it is advisable to diagnose the wear condition of the shaft coupling and replace the elastic body at the appropriate time.

One possible method for diagnosing the wear condition of a shaft coupling is to disconnect the prime mover from the driven machine, disassemble the shaft coupling, and diagnose the elastic body. However, this diagnostic method requires the disconnection of the prime mover from the driven machine, which requires cumbersome work, such as removing hydraulic piping attached to the driven machine, reattaching the piping after diagnosis, and disposing of hydraulic oil. In addition, this diagnostic method requires the preparation of crane equipment to hoist the driven machine, and the work location is limited. Therefore, even if this diagnostic method can accurately diagnose the wear condition of the shaft coupling, there is room for improvement in terms of workability, cost, etc.

In response to this, Patent Document 1 discloses a method of diagnosing the lifespan of an elastic body of a shaft coupling by providing a diagnostic protrusion on the outer circumferential surface of the elastic body. In the method disclosed in Patent Document 1, when the elastic body wears out, the drive shaft side block and the driven shaft side block engaged with the elastic body approach each other and press against the protrusion. By utilizing this, it is possible to visually check whether the protrusion has broken, thereby determining whether the elastic body needs to be replaced.

Patent Document 2 also discloses a method for diagnosing deterioration of a shaft coupling by providing the shaft coupling with a rotating piece made of a shape memory alloy designed and manufactured to deform into a specified shape when the temperature exceeds a set temperature, and measuring the degree of deformation of the rotating piece. The method disclosed in Patent Document 2 detects whether the sliding part in the shaft coupling has experienced an abnormal rise in temperature by utilizing the phenomenon in which the sliding part generates heat due to poor lubrication caused by deterioration of seals or insufficient oil supply.

JP 2015-72032 A Japanese Patent Application Publication No. 8-284967

However, in all of the methods disclosed in these patent documents, the wear condition of the shaft coupling can be diagnosed only when the wear condition of the shaft coupling has reached a serious stage, for example, when the wear condition has reached a serious stage where the drive shaft side block and the driven shaft side block engaged with the elastic body have come close to each other. With the methods disclosed in these patent documents, there is a possibility that a failure such as shaft breakage will occur before measures can be taken to prevent wear of the shaft coupling. Therefore, there is a demand for technology that can easily and precisely diagnose the wear condition of the shaft coupling.

In view of the above, the present invention aims to easily and precisely diagnose the wear condition of shaft couplings.

In order to solve the above problems, the shaft coupling diagnostic device according to the present invention is a shaft coupling diagnostic device that diagnoses the wear condition of a shaft coupling that connects a drive shaft that outputs the power of a prime mover and a driven shaft of a driven machine that is driven by the power transmitted from the drive shaft, and is characterized by having an operation sound acquisition unit that acquires the operation sound of the prime mover when the rotation speed of the prime mover is changed, a feature extraction unit that extracts abnormal sound components contained in the operation sound acquired by the operation sound acquisition unit as features, a wear model acquisition unit that acquires a wear model that shows the relationship between the abnormal sound components and the wear condition, and a wear condition diagnosis unit that diagnoses the wear condition based on the abnormal sound components extracted by the feature extraction unit and the wear model acquired by the wear model acquisition unit.

The shaft coupling diagnosis method according to the present invention is a shaft coupling diagnosis method for diagnosing the wear condition of a shaft coupling that connects a drive shaft that outputs the power of a prime mover and a driven shaft of a driven machine that is driven by the power transmitted from the drive shaft, and is characterized by including the steps of: acquiring the operating sound of the prime mover when the rotation speed of the prime mover is changed; extracting abnormal sound components contained in the acquired operating sound as features; and diagnosing the wear condition based on a wear model that shows the relationship between the abnormal sound components and the wear condition and the abnormal sound components extracted as the features.

The present invention makes it possible to easily and precisely diagnose the wear condition of a shaft coupling.

FIG. 2 is an exploded perspective view showing a schematic configuration of a shaft coupling. FIG. 2 is a block diagram showing a functional configuration of the shaft coupling diagnosis device according to the first embodiment. FIG. 3( a ) is a diagram showing the operating noise of the prime mover when wear of the shaft coupling has not yet progressed, and FIG. 3( b ) is a diagram showing the operating noise of the prime mover when wear of the shaft coupling has progressed to a certain extent. FIG. 1 is a diagram illustrating a wear model. 3 is a flowchart showing a shaft coupling diagnostic method using the shaft coupling diagnostic device shown in FIG. 2 . FIG. 6 is a block diagram showing a functional configuration of a shaft coupling diagnosis device according to a second embodiment. FIG. 11 is a block diagram showing a functional configuration of a shaft coupling diagnosis device according to a third embodiment. FIG. 13 is a block diagram showing a functional configuration of a shaft coupling diagnosis device according to a fourth embodiment.

Embodiments of the present invention will be described below with reference to the drawings. Components with the same reference numerals in each embodiment have the same functions in each embodiment unless otherwise specified, and the description thereof will be omitted.

[Embodiment 1]
A shaft coupling diagnosis device 1 according to a first embodiment will be described with reference to FIGS. 1 to 5. FIG.

Figure 1 is an exploded perspective view showing the configuration of the shaft coupling 80.

The shaft coupling 80 is a shaft coupling that connects a drive shaft 61 (e.g., the output shaft of an engine) that outputs the power of a prime mover 60 (e.g., an engine) to a driven shaft 71 (e.g., the rotating shaft of a hydraulic pump) of a driven machine 70 (e.g., a hydraulic pump) that is driven by the power transmitted from the drive shaft 61.

The shaft coupling 80 shown in FIG. 1 is an elastic shaft coupling that transmits the power output from the drive shaft 61 of the prime mover 60 to the driven shaft 71 of the driven machine 70 via an elastic body 85. The shaft coupling 80 absorbs the misalignment between the central axis of the drive shaft 61 and the central axis of the driven shaft 71, torque fluctuations of the prime mover 60, etc., by elastic deformation of the elastic body 85. The shaft coupling 80 is an elastic shaft coupling mounted on a construction machine such as a hydraulic excavator.

The shaft coupling 80 includes a drive shaft side block 81, a hub member 82, a driven shaft side block 83, and an elastic body 85.

The drive shaft side block 81 is formed as a roughly sector-shaped block body. The multiple drive shaft side blocks 81 are fixed to the flywheel 62 provided on the drive shaft 61 at intervals in the circumferential direction by screws or the like. A flange portion 81a extending in the circumferential direction is provided on both circumferential sides of the outer diameter side of the drive shaft side block 81. The flange portion 81a regulates the radial displacement of the elastic body 85.

The hub member 82 is formed as a thick-walled cylinder. The hub member 82 is fixed to the outer circumferential surface of the driven shaft 71 by a spline connection.

The driven shaft side block 83 is formed as a generally sector-shaped block body. The multiple driven shaft side blocks 83 are fixed to the outer circumferential surface of the hub member 82 at intervals in the circumferential direction by screws or the like. The driven shaft side blocks 83 are provided so as to protrude radially outward from the outer circumferential surface of the hub member 82. A flange portion 83a extending in the circumferential direction is provided on both circumferential sides of the outer diameter side of the driven shaft side block 83. The flange portion 83a restricts the radial displacement of the elastic body 85.

The elastic body 85 is formed as a thick cylindrical body made of rubber or the like. The inner peripheral surface of the elastic body 85 defines a housing portion 86 that houses the hub member 82. On the outer peripheral surface of the elastic body 85, a drive shaft side engaging portion 87 that engages with the drive shaft side block 81 and a driven shaft side engaging portion 88 that engages with the driven shaft side block 83 are formed alternately at intervals in the circumferential direction. The drive shaft side engaging portion 87 and the driven shaft side engaging portion 88 are formed as grooves recessed radially inward from the outer peripheral surface of the elastic body 85. The portion between the drive shaft side engaging portion 87 and the driven shaft side engaging portion 88 is a compression portion 89 that is compressed in the circumferential direction by the drive shaft side block 81 and the driven shaft side block 83.

The compression portion 89 of the elastic body 85 wears due to aging, deformation due to fatigue, etc., and the thickness in the circumferential direction decreases. Then, the flange portion 81a of the drive shaft side block 81 and the flange portion 83a of the driven shaft side block 83 approach each other. The compression portion 89 of the elastic body 85 wears further and the thickness in the circumferential direction decreases. If the wear of the elastic body 85 progresses in this way, the flange portion 81a and the flange portion 83a will eventually come into contact with each other, causing a failure such as shaft breakage. Therefore, it is important to diagnose the wear condition of the shaft coupling 80, and it is desirable to replace the elastic body 85 at the appropriate time.

Figure 2 is a block diagram showing the functional configuration of the shaft coupling diagnosis device 1 of embodiment 1.

The shaft coupling diagnostic device 1 is a device that diagnoses the wear condition of the shaft coupling 80. Specifically, the shaft coupling diagnostic device 1 is a device that diagnoses the wear condition of the elastic body 85 included in the shaft coupling 80 from the operating sound of the prime mover 60 connected to the shaft coupling 80.

The shaft coupling diagnostic device 1 is provided in a mobile terminal 10 such as a smartphone, tablet terminal, mobile phone, or PDA (Personal Data Assistant). The mobile terminal 10 includes a CPU (Central Processing Unit) that performs arithmetic processing, a ROM (Read Only Memory) as a secondary storage device that stores a program describing the arithmetic processing procedure, and a RAM (Random Access Memory) as a primary storage device that stores the calculation process and temporary control variables. The shaft coupling diagnostic device 1 is configured by the above-mentioned CPU and other components provided in the mobile terminal 10, and the various functions of the shaft coupling diagnostic device 1 are realized by the CPU executing the program.

The shaft coupling diagnostic device 1 includes a machine information acquisition unit 11, an operating sound acquisition unit 12, a feature extraction unit 13, a wear model acquisition unit 14, a wear condition diagnosis unit 15, and a diagnosis result output unit 16.

The machine information acquisition unit 11 acquires information on the shaft coupling 80 to be diagnosed. Specifically, the machine information acquisition unit 11 acquires information that identifies the model of the shaft coupling 80, which is determined according to the structure of the shaft coupling 80. The machine information acquisition unit 11 can acquire information that identifies the model of the shaft coupling 80 by the user inputting the model of the shaft coupling 80 or the construction machine from the screen of the mobile terminal 10.

The operation sound acquisition unit 12 is composed of a microphone built into the mobile terminal 10. The operation sound acquisition unit 12 acquires (records) the operation sound of the prime mover 60. The operation sound acquisition unit 12 outputs the acquired operation sound to the feature extraction unit 13. The position from which the operation sound of the prime mover 60 is acquired is not particularly limited, but it is preferable that it is a position close to the construction machine on which the shaft coupling 80 is mounted.

The operation sound acquisition unit 12 acquires the operation sound of the prime mover 60 when the rotation speed of the prime mover 60 is changed. Specifically, the operation sound acquisition unit 12 acquires the operation sound when the key is turned off on a construction machine in which the prime mover 60 is operating at the minimum rotation speed (low idling). When the key is turned off on a construction machine in which the prime mover 60 is operating at the minimum rotation speed, the rotation speed of the prime mover 60 changes from the minimum rotation speed to 0. In this case, the amplitude of the operation sound of the prime mover 60 shows a waveform that differs depending on the wear condition of the shaft coupling 80. Details of the operation sound of the prime mover 60 will be described later using Figures 3(a) and 3(b).

The feature extraction unit 13 extracts abnormal sound components contained in the operation sound acquired by the operation sound acquisition unit 12 as features for identifying the wear state of the shaft coupling 80. The abnormal sound components may be generated by changing the rotation speed of the prime mover 60 when the shaft coupling 80 is worn. Specifically, the feature extraction unit 13 extracts the amplitude of the operation sound that exceeds a predetermined threshold value during the period from when the construction machine is keyed off until the amplitude of the operation sound of the prime mover 60 converges as the abnormal sound component. The operation sound that includes the abnormal sound component is a sound that sounds like "clack" during the period from when the construction machine is keyed off until the amplitude of the operation sound of the prime mover 60 converges. The feature extraction unit 13 outputs the extracted abnormal sound components to the wear state diagnosis unit 15. Details of the abnormal sound components will be described later with reference to Figures 3(a) and 3(b).

The wear model acquisition unit 14 acquires a wear model that indicates the relationship between the abnormal sound components of the operating sound of the prime mover 60 and the wear state of the shaft coupling 80. Specifically, the wear model acquisition unit 14 acquires a wear model that indicates the relationship between the amount of wear of the elastic body 85 included in the shaft coupling 80 and the occurrence interval (time interval) of the abnormal sound component. The wear model may be a mathematical model that describes the relationship between the amount of wear of the elastic body 85 and the occurrence interval of the abnormal sound component. Based on the information of the shaft coupling 80 acquired by the machine information acquisition unit 11, the wear model acquisition unit 14 acquires a wear model corresponding to the model of the shaft coupling 80 specified by the information. The wear model acquisition unit 14 may acquire the wear model by reading a wear model registered in advance in a database or the like. The wear model acquisition unit 14 may acquire the wear model by generating a wear model from experimental data or the like stored in advance. The wear model acquisition unit 14 outputs the acquired wear model to the wear state diagnosis unit 15. Details of the wear model will be described later with reference to FIG. 4.

The wear condition diagnosis unit 15 diagnoses the wear condition of the shaft coupling 80 based on the abnormal sound components extracted by the feature extraction unit 13 and the wear model acquired by the wear model acquisition unit 14. Specifically, the wear condition diagnosis unit 15 estimates the wear amount of the elastic body 85 by applying the occurrence interval of the abnormal sound components extracted by the feature extraction unit 13 to the wear model acquired by the wear model acquisition unit 14. The wear condition diagnosis unit 15 may determine the risk of the shaft coupling 80 according to the estimated wear amount. The wear condition diagnosis unit 15 outputs the diagnosis result of the wear condition, including the estimation result of the wear amount and the judgment result of the risk level, to the diagnosis result output unit 16. The output method of the diagnosis result of the wear condition may be a method of outputting a number indicating the value of the wear amount, or a method of outputting a graph showing time on the horizontal axis (X axis) and an index of the wear amount on the vertical axis (Y axis). In the case of the method of outputting a graph, the display format of the graph is not particularly limited and may be, for example, a line graph, a bar graph, or the like. In the case of a method that outputs a graph, it is easy to predict the progress of wear over time. Since the risk of failure due to wear usually increases over time, it is possible to notify the user with text messages such as "Replacement recommended", "Replacement required", and "Inspection required" in order of the most recent elapsed time. Alternatively, the notification is not limited to text messages, and may be an icon display (blue, yellow, red) according to the progression of the risk of failure. The timing of the notification can be set as desired.

The diagnostic result output unit 16 outputs the diagnostic result output by the wear condition diagnosis unit 15. For example, the diagnostic result output unit 16 outputs the diagnostic result to the screen of the mobile terminal 10 and notifies the user of the diagnostic result by displaying the diagnostic result on the screen of the mobile terminal 10. The diagnostic result output unit 16 may also transmit the diagnostic result to a server device 30 that is communicably connected to the mobile terminal 10.

Figure 3(a) is a diagram showing the operating noise of the prime mover 60 when wear of the shaft coupling 80 has not yet progressed. Figure 3(b) is a diagram showing the operating noise of the prime mover 60 when wear of the shaft coupling 80 has progressed to a certain extent. The vertical axis of each of Figures 3(a) and 3(b) indicates the amplitude of the operating noise of the prime mover 60. The horizontal axis of each of Figures 3(a) and 3(b) indicates time.

When wear of the shaft coupling 80 has not yet progressed, as shown in FIG. 3(a), in the period prior to time T1 when the construction machine is keyed off, the amplitude of the operation sound of the prime mover 60 is generally constant, except for fluctuations due to noise, etc. After time T1 when the key is turned off, the amplitude of the operation sound of the prime mover 60 gradually decreases and converges at time T2. After time T2, the amplitude of the operation sound of the prime mover 60 remains converged and generally constant. Time T2 when the amplitude of the operation sound of the prime mover 60 converges indicates the time when the operation sound is silenced.

The operation sound acquisition unit 12 acquires the operation sound of the prime mover 60 over a period Te including a time period T1 from the time when the construction machine is keyed off to a time period T3 that is a predetermined time after a time period T2 at which the amplitude of the operation sound of the prime mover 60 converges.

When wear of the shaft coupling 80 has progressed to a certain extent, as shown in FIG. 3(b), in the period before time T1 when the construction machine is keyed off, the amplitude of the operation sound of the prime mover 60 is roughly constant, as in the case of FIG. 3(a). After time T2, the amplitude of the operation sound of the prime mover 60 is roughly constant, as in the case of FIG. 3(a). On the other hand, in the period Tc from time T1 when the key is turned off to time T2 when the amplitude of the operation sound converges, the amplitude of the operation sound of the prime mover 60 produces peaks P1 to P6 that indicate abnormal sound components. Peaks P1 to P6 are the amplitude of the operation sound that exceeds a predetermined threshold. This threshold can be calculated in advance by experiment, etc.

The feature extraction unit 13 cuts out the operation sound from the operation sound acquired by the operation sound acquisition unit 12 during a period Te from time T1 when the construction machine is keyed off to time T3, a predetermined time after time T2 when the amplitude of the operation sound of the prime mover 60 converges. The feature extraction unit 13 then extracts the amplitude of the operation sound (peaks P1 to P6) that exceeds a predetermined threshold during the period Tc from time T1 when the construction machine is keyed off to when the amplitude of the operation sound of the prime mover 60 converges as an abnormal sound component. Note that the feature extraction unit 13 may also extract the amplitude of the operation sound that is equal to or less than the predetermined threshold during the period Tc as a normal sound component, and output it to the wear condition diagnosis unit 15.

Figure 4 is a diagram explaining the wear model. The vertical axis of Figure 4 shows the average occurrence interval of abnormal sound components. The horizontal axis of Figure 4 shows the amount of wear of the elastic body 85 included in the shaft coupling 80.

As shown in FIG. 4, it can be seen that as the amount of wear of the elastic body 85 increases, the occurrence interval (time interval) of the abnormal sound components increases. The wear model can be described as an approximation equation of a graph as shown in FIG. 4, which shows the relationship between the amount of wear of the elastic body 85 and the occurrence interval of the abnormal sound components. The wear model acquisition unit 14 acquires a wear model as shown in FIG. 4 according to the model of the shaft coupling 80. The wear status diagnosis unit 15 can estimate the amount of wear of the elastic body 85 included in the shaft coupling 80 by substituting the occurrence interval of the abnormal sound components extracted by the feature extraction unit 13 into the approximation equation of the graph as shown in FIG. 4.

Figure 5 is a flowchart showing a method for diagnosing a shaft coupling using the shaft coupling diagnosis device 1 shown in Figure 2.

First, the user starts the application software of the shaft coupling diagnostic device 1 installed on the mobile terminal 10. The shaft coupling diagnostic device 1 displays on the screen of the mobile terminal 10 a diagnostic procedure that prompts the user to prepare the construction machine so that the prime mover 60 operates at the minimum rotation speed. The shaft coupling diagnostic device 1 displays on the screen of the mobile terminal 10 a form for inputting the model of the shaft coupling 80 or construction machine to be diagnosed. The user prepares the construction machine and inputs the shaft coupling 80 or construction machine model from the screen of the mobile terminal 10.

In step S101, the shaft coupling diagnostic device 1 acquires information for identifying the model of the shaft coupling 80 by the user inputting the model of the shaft coupling 80 or the construction machine from the screen of the mobile terminal 10. The shaft coupling diagnostic device 1 displays, on the screen of the mobile terminal 10, a diagnostic procedure that prompts the user to acquire the operating sound of the prime mover 60 at the optimal position for acquiring the operating sound. The user moves the mobile terminal 10 according to the diagnostic procedure displayed on the screen of the mobile terminal 10.

In step S102, the shaft coupling diagnosis device 1 acquires a wear model corresponding to the type of shaft coupling 80 identified by the acquired information identifying the type of shaft coupling 80.

In step S103, the shaft coupling diagnostic device 1 acquires the operating sound when the prime mover 60 is turned off while the construction machine is operating at the minimum rotation speed. The shaft coupling diagnostic device 1 displays on the screen of the mobile terminal 10 a diagnostic procedure that prompts the user to acquire the operating sound of the prime mover 60 over a period including the period Te. The user follows the diagnostic procedure displayed on the screen of the mobile terminal 10 to turn off the key of the construction machine and acquire the operating sound.

In step S104, the shaft coupling diagnostic device 1 extracts the operation sounds during the period Te from the acquired operation sounds. Then, the shaft coupling diagnostic device 1 extracts, from the extracted operation sounds, the amplitude of the operation sounds that exceeds a predetermined threshold during the period Tc as an abnormal sound component.

In step S105, the shaft coupling diagnostic device 1 diagnoses the wear condition of the shaft coupling 80 based on the extracted abnormal sound components and the acquired wear model. Specifically, the shaft coupling diagnostic device 1 calculates the occurrence interval of the extracted abnormal sound components. The shaft coupling diagnostic device 1 estimates the amount of wear of the elastic body 85 included in the shaft coupling 80 by applying the calculated occurrence interval of the abnormal sound components to the acquired wear model.

In step S106, the shaft coupling diagnosis device 1 outputs the diagnosis result to the screen of the mobile terminal 10 and notifies the user. The shaft coupling diagnosis method shown in FIG. 5 ends.

The shaft coupling diagnosis device 1 may change the order in which step S102 is performed as long as it is between step S101 and step S105.

As described above, the shaft coupling diagnostic device 1 of the first embodiment is a device for diagnosing the wear condition of the shaft coupling 80 that connects the drive shaft 61 that outputs the power of the prime mover 60 and the driven shaft 71 of the driven machine 70 that is driven by the power transmitted from the drive shaft 61. The shaft coupling diagnostic device 1 includes an operation sound acquisition unit 12 that acquires the operation sound of the prime mover 60 when the rotation speed of the prime mover 60 is changed. The shaft coupling diagnostic device 1 includes a feature extraction unit 13 that extracts, as a feature, an abnormal sound component contained in the operation sound acquired by the operation sound acquisition unit 12. The shaft coupling diagnostic device 1 includes a wear model acquisition unit 14 that acquires a wear model that indicates the relationship between the abnormal sound component and the wear condition. The shaft coupling diagnostic device 1 includes a wear condition diagnosis unit 15 that diagnoses the wear condition of the shaft coupling 80 based on the abnormal sound component extracted by the feature extraction unit 13 and the wear model acquired by the wear model acquisition unit 14.

With this configuration, the shaft coupling diagnostic device 1 can diagnose the wear condition of the shaft coupling 80 without disconnecting the prime mover 60 and the driven machine 70 and disassembling the shaft coupling 80. Furthermore, the shaft coupling diagnostic device 1 can diagnose the wear condition of the shaft coupling 80 from a stage where the wear is minor, even before the wear condition of the shaft coupling 80 reaches a serious stage, by utilizing the occurrence of abnormal sound components in the operating sound of the prime mover 60. Therefore, the shaft coupling diagnostic device 1 can easily and precisely diagnose the wear condition of the shaft coupling.

Furthermore, in the shaft coupling diagnostic device 1, the shaft coupling 80 may be an elastic shaft coupling mounted on a construction machine. The operation sound acquisition unit 12 acquires operation sounds when the construction machine is keyed off while the prime mover 60 is operating at the minimum rotation speed. The feature extraction unit 13 extracts, as an abnormal sound component, the amplitude of the operation sound that exceeds a predetermined threshold during the period Tc from when the construction machine is keyed off until the amplitude of the operation sound converges.

As a result, the shaft coupling diagnostic device 1 can stably acquire the operating sound of the prime mover 60 by always maintaining the same conditions for the states of the prime mover 60, the driven machine 70, and the shaft coupling 80 when diagnosing the shaft coupling 80. In addition, the shaft coupling diagnostic device 1 can clearly distinguish whether or not the operating sound of the prime mover 60 contains abnormal sound components caused by wear of the shaft coupling 80, and can accurately extract only those abnormal sound components. Therefore, the shaft coupling diagnostic device 1 can not only easily and precisely diagnose the wear condition of the shaft coupling 80, but also diagnose it accurately and stably.

Furthermore, the wear model acquisition unit 14 acquires a wear model that indicates the relationship between the amount of wear of the elastic body 85 included in the shaft coupling 80 and the occurrence interval of the abnormal sound component. The wear status diagnosis unit 15 estimates the amount of wear of the elastic body 85 by applying the occurrence interval of the abnormal sound component extracted by the feature extraction unit 13 to the wear model acquired by the wear model acquisition unit 14.

As a result, the shaft coupling diagnostic device 1 can quantitatively indicate the extent to which wear of the elastic body 85 has progressed using a relatively simple method, making it possible to detect signs of an abnormality occurring in the shaft coupling 80. As a result, the shaft coupling diagnostic device 1 can not only diagnose the wear condition of the shaft coupling 80 more precisely, but also optimize the maintenance plan for the shaft coupling 80, such as the timing of replacing the elastic body 85. The shaft coupling diagnostic device 1 can significantly reduce the downtime of construction machinery, thereby improving the productivity of the construction machinery.

Furthermore, the operation sound acquisition unit 12, the feature extraction unit 13, the wear model acquisition unit 14, and the wear condition diagnosis unit 15 may be provided in the mobile terminal 10.

As a result, the shaft coupling diagnostic device 1 allows anyone at the work site to easily diagnose the wear condition of the shaft coupling 80. Therefore, the shaft coupling diagnostic device 1 can diagnose the wear condition of the shaft coupling 80 even more easily.

The shaft coupling diagnosis method of the first embodiment is a shaft coupling diagnosis method for diagnosing the wear condition of the shaft coupling 80 that connects the drive shaft 61 that outputs the power of the prime mover 60 and the driven shaft 71 of the driven machine 70 that is driven by the power transmitted from the drive shaft 61. The shaft coupling diagnosis method includes acquiring the operation sound of the prime mover 60 when the rotation speed of the prime mover 60 is changed (step S103). The shaft coupling diagnosis method includes extracting an abnormal sound component contained in the acquired operation sound as a feature (step S104). The shaft coupling diagnosis method includes diagnosing the wear condition of the shaft coupling 80 based on a wear model that shows the relationship between the abnormal sound component and the wear condition and the abnormal sound component extracted as the feature (step S105).

As a result, the shaft coupling diagnosis method can diagnose the wear condition of the shaft coupling 80 without disconnecting the prime mover 60 and the driven machine 70 and disassembling the shaft coupling 80. Furthermore, the shaft coupling diagnosis method can diagnose the wear condition of the shaft coupling 80 from a stage where the wear is minor, even before the wear condition of the shaft coupling 80 reaches a serious stage, by utilizing the occurrence of abnormal sound components in the operating sound of the prime mover 60. Therefore, the shaft coupling diagnosis method can easily and precisely diagnose the wear condition of the shaft coupling.

Furthermore, the shaft coupling 80 may be an elastic shaft coupling mounted on the construction machine. Acquiring the operation sound means acquiring the operation sound when the construction machine operating with the prime mover 60 at the minimum rotation speed is keyed off. Extracting the abnormal sound component means extracting the amplitude of the operation sound that exceeds a predetermined threshold value during the period Tc from when the construction machine is keyed off until the amplitude of the operation sound converges as the abnormal sound component.

As a result, the shaft coupling diagnosis method can stably obtain the operating sound of the prime mover 60 by always maintaining the same conditions for the prime mover 60, the driven machine 70, and the shaft coupling 80 when diagnosing the shaft coupling 80. In addition, the shaft coupling diagnosis method can clearly distinguish whether or not the operating sound of the prime mover 60 contains abnormal sound components caused by wear of the shaft coupling 80, and can accurately extract only the abnormal sound components. Therefore, the shaft coupling diagnosis method can not only easily and precisely diagnose the wear condition of the shaft coupling 80, but also diagnose it accurately and stably.

[Embodiment 2]
A shaft coupling diagnosis device 1 of the second embodiment will be described with reference to Fig. 6. In the shaft coupling diagnosis device 1 of the second embodiment, the description of the same configuration and operation as those of the first embodiment will be omitted.

Figure 6 is a block diagram showing the functional configuration of the shaft coupling diagnosis device 1 of embodiment 2.

In the shaft coupling diagnostic device 1 of the second embodiment, the machine information acquisition unit 11 and the operating sound acquisition unit 12 are provided in the mobile terminal 10. In the shaft coupling diagnostic device 1 of the second embodiment, the feature extraction unit 13, the wear model acquisition unit 14, the wear condition diagnosis unit 15, and the diagnosis result output unit 16 are provided in a server device 30 that can communicate with the mobile terminal 10.

The server device 30 is equipped with a CPU, ROM, and RAM, and is installed in a management sensor of a construction machine, etc. The shaft coupling diagnosis device 1 of the third embodiment is configured by the above-mentioned CPU, etc. provided in the server device 30, and the CPU executes a program to realize various functions of the shaft coupling diagnosis device 1.

The machine information acquisition unit 11 of the second embodiment transmits the acquired information of the shaft coupling 80 to the wear model acquisition unit 14 provided in the server device 30. The operating sound acquisition unit 12 of the second embodiment transmits the acquired operating sound of the prime mover 60 to the feature extraction unit 13 provided in the server device 30. The diagnosis result output unit 16 of the second embodiment transmits the diagnosis result to the mobile terminal 10 to display it on the screen of the mobile terminal 10, or transmits the diagnosis result to the construction machine to display it on a display device provided in the construction machine. In this case, if an emergency response is required, the mobile terminal 10 may simply display only the event using the above-mentioned lantern display function, while detailed information such as the diagnosis result may be displayed on the display device of the construction machine, and the notification destination of the diagnosis result may be different.

In this way, in the shaft coupling diagnostic device 1 of embodiment 2, the feature extraction unit 13, the wear model acquisition unit 14, and the wear condition diagnosis unit 15 are provided in the server device 30, so that the processing related to these functions can be made faster than in embodiment 1. Therefore, the shaft coupling diagnostic device 1 of embodiment 2 can diagnose the wear condition of the shaft coupling 80 more quickly than in embodiment 1. Furthermore, by using the server device 30, the shaft coupling diagnostic device 1 can easily analyze the progress of the wear condition of the shaft coupling 80 and the detailed causes of wear, and collect the diagnosis results of the shaft couplings 80 of other construction machines and centrally manage the wear condition of the shaft coupling 80.

[Embodiment 3]
A shaft coupling diagnosis device 1 of the third embodiment will be described with reference to Fig. 7. In the shaft coupling diagnosis device 1 of the third embodiment, the description of the same configuration and operation as those of the first embodiment will be omitted.

Figure 7 is a block diagram showing the functional configuration of the shaft coupling diagnosis device 1 of embodiment 3.

In the shaft coupling diagnostic device 1 of the third embodiment, a machine information acquisition unit 11, an operating sound acquisition unit 12, a feature extraction unit 13, a wear model acquisition unit 14, a wear condition diagnosis unit 15, and a diagnosis result output unit 16 are provided in the control device 20 of the construction machine.

The control device 20 is configured with a microcomputer that combines a CPU, a ROM, and a RAM. The shaft coupling diagnostic device 1 of embodiment 3 is configured with the above-mentioned CPU and other components provided in the control device 20, and the CPU executes a program to change the rotation speed of the prime mover 60 and obtain the operating sound of the prime mover 60 using a microphone installed on the construction machine.

The machine information acquisition unit 11 of the third embodiment acquires information on the shaft coupling 80 directly from the control device 20 at the start of diagnosis. The operation sound acquisition unit 12 of the third embodiment starts acquiring the operation sound of the prime mover 60 based on a command from the control device 20. For example, event information indicating the occurrence of key-off of the construction machine is predefined in the control device 20, and when the construction machine is keyed off, the control device 20 outputs the event information to the operation sound acquisition unit 12. When the event information is input, the operation sound acquisition unit 12 starts acquiring the operation sound. In addition, the diagnosis result output unit 16 of the third embodiment displays the diagnosis result on a display device provided on the construction machine, outputs it as an alarm, or transmits it to the server device 30. The notification content and notification destination of the diagnosis result can be set arbitrarily. That is, when an emergency response is required, the mobile terminal 10 may simply display only the event using the above-mentioned lantern display function, while detailed information such as the diagnosis result may be displayed on the display device of the construction machine. In addition, the notification destination of the diagnosis result may be set arbitrarily according to the progression of the failure risk. For example, if the problem can be solved by an inspector at the work site taking immediate action, it may be possible to respond more quickly by notifying the mobile terminal 10 held by the inspector. For this reason, the urgency of the risk of failure may be determined, and if the urgency is high, the notification may be sent to both the mobile terminal 10 and the server device 30, and the number of notification destinations is not necessarily limited to one.

In this way, in the shaft coupling diagnosis device 1 of embodiment 3, the machine information acquisition unit 11, the operating sound acquisition unit 12, the feature extraction unit 13, the wear model acquisition unit 14, the wear condition diagnosis unit 15, and the diagnosis result output unit 16 are provided in the control device 20 of the construction machine, so that the wear condition of the shaft coupling 80 can be diagnosed on the construction machine side without going to the work site. Furthermore, by the control device 20 of the construction machine transmitting the diagnosis result together with the operation information of the construction machine to the server device 30, etc., the server device 30 can easily analyze the progress of the wear condition of the shaft coupling 80 and the detailed cause of wear, and collect the diagnosis results of the shaft couplings 80 of other construction machines to centrally manage the wear condition of the shaft coupling 80.

[Embodiment 4]
A shaft coupling diagnosis device 1 of the fourth embodiment will be described with reference to Fig. 8. In the shaft coupling diagnosis device 1 of the fourth embodiment, the description of the same configuration and operation as those of the third embodiment will be omitted.

Figure 8 is a block diagram showing the functional configuration of the shaft coupling diagnosis device 1 of embodiment 4.

In the shaft coupling diagnostic device 1 of the fourth embodiment, the machine information acquisition unit 11 and the operating sound acquisition unit 12 are provided in the control device 20 of the construction machine. In the shaft coupling diagnostic device 1 of the fourth embodiment, the feature extraction unit 13, the wear model acquisition unit 14, the wear condition diagnosis unit 15, and the diagnosis result output unit 16 are provided in a server device 30 that can communicate with the construction machine.

The machine information acquisition unit 11 of the fourth embodiment transmits the acquired information of the shaft coupling 80 to the server device 30. The operation sound acquisition unit 12 of the fourth embodiment transmits the acquired operation sound of the prime mover 60 to the server device 30. The diagnosis result output unit 16 of the fourth embodiment transmits the diagnosis result to the construction machine to be displayed on a display device provided on the construction machine, or transmits the diagnosis result to the mobile terminal 10 to be displayed on the screen of the mobile terminal 10.

In this way, in the shaft coupling diagnosis device 1 of embodiment 4, the feature extraction unit 13, the wear model acquisition unit 14, and the wear condition diagnosis unit 15 are provided in the server device 30, so that the processing related to these functions can be made faster than in embodiment 3. Therefore, the shaft coupling diagnosis device 1 of embodiment 4 can diagnose the wear condition of the shaft coupling 80 more quickly than in embodiment 3.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the present invention described in the claims. The present invention allows the configuration of one embodiment to be added to the configuration of another embodiment, the configuration of one embodiment to be replaced with another embodiment, or part of the configuration of one embodiment to be deleted.

1...shaft coupling diagnostic device, 10...mobile terminal, 11...machine information acquisition unit, 12...operating sound acquisition unit, 13...feature extraction unit, 14...wear model acquisition unit, 15...wear status diagnosis unit, 20...control device, 30...server device, 60...prime mover, 61...drive shaft, 70...driven machine, 71...driven shaft, 80...shaft coupling, 85...elastic body

Claims (9)

A shaft coupling diagnostic device for diagnosing a wear condition of a shaft coupling connecting a drive shaft that outputs power of a prime mover and a driven shaft of a driven machine that is driven by the power transmitted from the drive shaft, comprising:
an operation sound acquisition unit that acquires an operation sound of the prime mover when a rotation speed of the prime mover is changed;
a feature extraction unit that extracts, as a feature, an abnormal sound component contained in the operation sound acquired by the operation sound acquisition unit;
a wear model acquisition unit that acquires a wear model indicating a relationship between the abnormal sound component and the wear state;
a wear condition diagnosis unit that diagnoses the wear condition based on the abnormal sound component extracted by the feature extraction unit and the wear model acquired by the wear model acquisition unit. The shaft coupling is an elastic shaft coupling mounted on a construction machine,
the operation sound acquisition unit acquires the operation sound when the key is turned off on the construction machine while the prime mover is operating at a minimum rotation speed,
The shaft coupling diagnosis device according to claim 1, characterized in that the feature extraction unit extracts, as the abnormal sound component, an amplitude of the operation sound that exceeds a predetermined threshold during a period from when the construction machine is keyed off to when the amplitude of the operation sound converges. the wear model acquisition unit acquires the wear model indicating a relationship between an amount of wear of an elastic body included in the shaft coupling and an occurrence interval of the abnormal sound component,
3. The shaft coupling diagnosis device according to claim 2, wherein the wear condition diagnosis unit estimates the amount of wear of the elastic body by applying an occurrence interval of the abnormal sound component extracted by the feature extraction unit to the wear model acquired by the wear model acquisition unit. The shaft coupling diagnosis device according to claim 1 , wherein the operation sound acquisition unit, the feature amount extraction unit, the wear model acquisition unit, and the wear condition diagnosis unit are provided in a mobile terminal. The operation sound acquisition unit is provided in a mobile terminal,
The shaft coupling diagnosis device according to claim 1 , wherein the feature amount extraction unit, the wear model acquisition unit, and the wear condition diagnosis unit are provided in a server device capable of communicating with the mobile terminal. The shaft coupling is mounted on a construction machine,
The shaft coupling diagnosis device according to claim 1 , wherein the operation sound acquisition unit, the feature amount extraction unit, the wear model acquisition unit and the wear condition diagnosis unit are provided in the construction machine. The shaft coupling is mounted on a construction machine,
The operation sound acquisition unit is provided in the construction machine,
The shaft coupling diagnosis device according to claim 1, wherein the feature amount extraction unit, the wear model acquisition unit, and the wear condition diagnosis unit are provided in a server device capable of communicating with the construction machine. 1. A shaft coupling diagnosis method for diagnosing a wear state of a shaft coupling that connects a drive shaft that outputs power of a prime mover to a driven shaft of a driven machine that is driven by the power transmitted from the drive shaft, comprising:
Acquiring an operation sound of the prime mover when a rotation speed of the prime mover is changed;
Extracting an abnormal sound component contained in the acquired operation sound as a feature amount;
diagnosing the wear state based on a wear model indicating a relationship between the abnormal sound component and the wear state, and on the abnormal sound component extracted as the feature amount. The shaft coupling is an elastic shaft coupling mounted on a construction machine,
The acquisition of the operation sound is acquisition of the operation sound when the key of the construction machine is turned off while the prime mover is operating at a minimum rotation speed,
The extraction of the abnormal sound component is to extract, as the abnormal sound component, the amplitude of the operation sound that exceeds a predetermined threshold during a period from when the construction machine is keyed off to when the amplitude of the operation sound converges.
9. The shaft coupling diagnosis method according to claim 8.

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