Sound diagnostic system, information processing device, and program

The sound diagnostic system in image forming apparatuses detects unknown abnormal sounds by processing sound wave data over time intervals and setting thresholds, accurately identifying the replacement unit causing the sound, thus anticipating potential failures.

JP7883377B2Active Publication Date: 2026-07-01CANON KK

Patent Information

Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
CANON KK
Filing Date
2022-03-17
Publication Date
2026-07-01

AI Technical Summary

Technical Problem

Existing sound detection systems in image forming apparatuses can only identify known abnormal sounds, failing to detect unknown abnormal sounds that may indicate the need for replacement of worn-out parts.

Method used

A sound diagnostic system that processes sound wave data over time intervals, classifies operating states of actuators, and sets thresholds to detect unknown abnormal sounds by comparing sound wave levels with predetermined thresholds, identifying the replacement unit causing the abnormal sound.

Benefits of technology

Enables detection of unknown abnormal sounds and accurate identification of the replacement unit generating the sound, even when the sound is not previously recognized, thereby anticipating potential failures.

✦ Generated by Eureka AI based on patent content.

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Patent Text Reader

Abstract

To provide a technique for detecting generation of an abnormal sound even if the abnormal sound is an unknown sound.SOLUTION: A sound diagnosis system includes: generation means configured to process a signal indicating a sound wave level in a predetermined period received by reception means, and generate sound data indicating a sound wave level in each of a plurality of time sections and an operation status of one or more actuators in each of the plurality of time sections, the plurality of time sections being obtained by dividing the predetermined period; classification means configured to classify and group the sound data based on a difference of operation status of the one or more actuators; setting means configured to set a threshold for each of the plurality of time sections, based on a sound wave level in each of the plurality of time sections of multiple pieces of first sound data classified in a first group; and determination means configured to determine whether or not an abnormal sound is generated by comparing a comparison value for each of the plurality of time sections based on a sound wave level in each of the plurality of time sections of one or more pieces of second sound data classified in the first group, with a threshold determined for a corresponding time section.SELECTED DRAWING: Figure 9
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Description

Technical Field

[0006] , ,

[0005] , , ,

[0001] The present invention relates to a technique for determining whether an abnormal sound is generated during the operation of a device.

Background Art

[0002] Image forming apparatuses such as copiers and laser printers have replacement parts (replacement units) that are replaced according to their lifespan. When a replacement unit is used beyond its lifespan, a sound different from the normal operating sound (hereinafter referred to as an abnormal sound) may occur. For example, a feeding unit that conveys sheets may generate an abnormal sound due to wear between the shaft and bearing of its conveyance roller. The occurrence of an abnormal sound is an indicator that a replacement unit has exceeded its lifespan or that a failure of the replacement unit is about to occur, and it may also cause discomfort to the user. Therefore, it is desirable to determine the occurrence of an abnormal sound and identify the replacement unit that is generating the abnormal sound.

[0003] Patent Document 1 discloses a configuration in which a microphone is arranged inside an image forming apparatus and compared with known abnormal sounds to detect whether an abnormal sound is generated and the component that is generating the abnormal sound.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, the configuration of Patent Document 1 can only be applied when the abnormal sound is known.

[0006] The present invention provides a technique for detecting the occurrence of an unknown abnormal sound.

Means for Solving the Problems

[0007] According to one aspect of the present invention, a sound diagnostic system includes a receiving means for receiving sound waves in a device having one or more actuators, A control means, The receiving means processes the signal indicating sound waves received over a predetermined period and generates sound data indicating the sound wave level for each of the multiple time intervals into which the predetermined period is divided, and the operating state of one or more actuators for each of the multiple time intervals. death , the operating state of one or more actuators in each of the plurality of time intervals difference Based on the above sound data , including the first group and several group Classified Each of the aforementioned multiple time intervals of threshold The threshold is generated using the sound wave levels of each of the multiple time intervals of the multiple first sound data classified into the first group. Based on the sound wave level of each of the multiple time intervals of one or more second sound data classified into the first group, the comparison value of each of the multiple time intervals is determined. Seeking, The comparison values ​​for each of the aforementioned multiple time intervals However, The threshold value for the corresponding time interval of the first group The control means for determining whether it is greater than or less, It is equipped with. [Effects of the Invention]

[0008] According to the present invention, even if an abnormal sound is unknown, its occurrence can be detected. [Brief explanation of the drawing]

[0009] [Figure 1] A schematic diagram of an image forming apparatus according to one embodiment. [Figure 2] A diagram showing the configuration of a MEMS microphone in the receiving section according to one embodiment. [Figure 3] Hardware configuration diagram of a sound diagnostic system according to one embodiment. [Figure 4] A functional block diagram of a sound diagnostic system according to one embodiment. [Figure 5] A flowchart of the threshold setting process according to one embodiment. [Figure 6] A figure showing the classification results based on actuator states according to one embodiment. [Figure 7]A diagram showing the relationship between statistical values and threshold values according to an embodiment. [Figure 8] A diagram showing the relationship between statistical values and threshold values according to an embodiment. [Figure 9] A flowchart of a process for determining whether an abnormal sound is occurring and the replacement unit causing the abnormal sound according to an embodiment. [Figure 10] An explanatory diagram of a process for determining the replacement unit causing an abnormal sound according to an embodiment. [Figure 11] A flowchart of a threshold setting process according to an embodiment. [Figure 12] An explanatory diagram of a threshold setting process according to an embodiment. [Figure 13] A flowchart of a process for determining whether an abnormal sound is occurring and the replacement unit causing the abnormal sound according to an embodiment.

MODE FOR CARRYING OUT THE INVENTION

[0010] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the invention according to the claims. Although a plurality of features are described in the embodiments, not all of these plurality of features are essential to the invention, and the plurality of features may be arbitrarily combined. Further, in the accompanying drawings, the same or similar configurations are denoted by the same reference numerals, and redundant descriptions are omitted.

[0011] <First Embodiment> FIG. 1 is a schematic configuration diagram of an image forming apparatus PR according to the present embodiment. The image forming apparatus PR includes cartridges 5Y, 5M, 5C, and 5K that form yellow, magenta, cyan, and black toner images on an intermediate transfer member 11. The cartridges 5Y, 5M, 5C, and 5K contain different colors of toner, but have the same configuration, and are hereinafter generically referred to as cartridge 5. The cartridge 5 includes a photoreceptor 1, a charging roller 2, and a developing roller 3, and is configured to be detachable from the main body of the image forming apparatus PR. That is, the cartridge 5 is an exchange unit of the image forming apparatus PR. The photoreceptor 1 is rotationally driven in the clockwise direction in the figure during image formation. The charging roller 2 charges the surface of the photoreceptor 1. The scanning unit 8 exposes each photoreceptor 1 based on image data and forms an electrostatic latent image on each photoreceptor 1. The developing roller 3 develops the electrostatic latent image of the photoreceptor 1 with toner to form a toner image on the photoreceptor 1. The primary transfer rollers 10Y, 10M, 10C, and 10K transfer the toner images of the photoreceptors 1 of the cartridges 5Y, 5M, 5C, and 5K to the intermediate transfer member 11, respectively.

[0012] The intermediate transfer unit includes the intermediate transfer member 11, a plurality of rollers including a driving roller 15 for stretching the intermediate transfer member 11, and the primary transfer rollers 10Y, 10M, 10C, and 10K. The intermediate transfer unit is an exchange unit of the image forming apparatus PR. During image formation, the driving roller 15 is rotationally driven in the counterclockwise direction in the figure by a motor (not shown). Thereby, the intermediate transfer member 11 is also rotationally driven in the counterclockwise direction in the figure. Therefore, the toner image on the intermediate transfer member 11 is conveyed to the opposing position of the secondary transfer roller 14.

[0013] The feeding roller 22 of the feeding unit 20 feeds the recording material S contained in the cassette 21 to the transport path of the image forming apparatus PR. The transport roller 23 transports the recording material S fed by the feeding roller 22 downstream. The separation roller 24 is provided to prevent double feeding. The registration roller 25 transports the recording material S toward the position opposite the secondary transfer roller 14. The feeding roller 22, transport roller 23, and registration roller 25 are each interchangeable units of the image forming apparatus PR. The secondary transfer roller 14 transfers the toner image of the intermediate transfer body 11 to the recording material S. The fixing unit 30 has a fixing film 31 and a pressure roller 32, and fixes the toner image to the recording material S by heating and pressurizing the recording material S. The fixing unit 30 is an interchangeable unit of the image forming apparatus PR. After the toner image is fixed, the recording material S is discharged to the outside of the image forming apparatus PR by the discharge roller 33. The transport sensor 90 is located downstream of the registration roller 25 and detects the recording material S. A receiving unit 71 for receiving sound waves is provided between the transport sensor 90 and the secondary transfer roller 14. For example, the receiving unit 71 has a MEMS (Micro Electro Mechanical System) microphone that converts the vibrational displacement of a diaphragm due to pressure into a voltage change and outputs it. However, if it is possible to receive sound waves, a microphone other than a MEMS microphone, such as a condenser microphone, can also be used.

[0014] Figure 2 is a cross-sectional view showing an example of a MEMS microphone in the receiving unit 71. A MEMS chip 71a and an amplification circuit 71c are provided on the substrate 71b. The MEMS chip 71a and the amplification circuit 71c are shielded by a shield case 72. The shield case 72 is provided with a sound hole 72a for taking in sound waves from the outside. The MEMS chip 71a and the amplification circuit 71c are electrically connected by a wire 71d. The MEMS chip 71a has a diaphragm 71f formed on a silicon substrate 71e and a back electrode 71h provided opposite the diaphragm 71f and having a number of sound holes. The opposing diaphragm 71f and back electrode 71h form a capacitor. A cavity 71g is provided in the silicon substrate 71e, and the diaphragm 71f is provided so as to cover this cavity 71g. When sound waves are input through the sound hole 72a provided in the shield case 72, the diaphragm 71f vibrates, and an electrical signal corresponding to the vibration state is output. More specifically, the back electrode 71h converts the change in capacitance of the capacitor formed by the diaphragm 71f and the back electrode 71h, caused by the vibration of the diaphragm 71f, into an electrical signal. This electrical signal is amplified by the amplification circuit 71c and then output outside the MEMS microphone.

[0015] Figure 3 is a configuration diagram of a sound diagnostic system or image forming system including an image forming apparatus PR according to this embodiment. As shown in Figure 3, the host computer HC, the image forming apparatus PR, and the server SV, which is an information processing device, are configured to communicate with each other, for example, via a network. The control unit 201 of the host computer HC includes a CPU, which is a processor, and performs various processes by executing a control program stored in a storage device (not shown). The operation display unit 202 includes a display, keyboard, mouse, etc., and provides a user interface. For example, in response to user operations on the operation display unit 202, the control unit 201 sends a print job including image data to the image forming apparatus PR, causing the image forming apparatus PR to form an image based on the image data.

[0016] The video controller 85 of the image forming apparatus PR performs communication processing with the host computer HC and the server SV. When the video controller 85 receives a print job from the host computer HC, it controls the image formation based on the print job by the printer engine 84. The operation display unit 86 includes an operation panel and operation buttons, etc., and provides a user interface. The printer engine 84 has an engine control unit 87 which includes a processor CPU 80, ROM 81, and RAM 82. ROM 81 is a non-volatile memory that holds and stores control programs and various data. Note that a rewritable non-volatile memory can be used instead of ROM 81. RAM 82 is a volatile memory that stores temporary data. The CPU 80 executes the control program stored in ROM 81 and controls the components shown in Figure 1, and the motors 91-95 and solenoid 96 shown in Figure 3, via I / O port 83 to form an image on the sheet S.

[0017] The feed motor 91 is the drive source for the feed roller 22, the transport roller 23, and the registration roller 25. The intermediate transfer body motor 92 is the drive source for the drive roller 15. The photoreceptor motor 93 is the drive source for each photoreceptor 1. The developing motor 94 is the drive source for each developing roller 3. The fixing motor 95 is the drive source for the pressure roller 32 of the fixing unit 30. The solenoid 96 is the drive source for a mechanical clutch mechanism (not shown) that separates the primary transfer roller 10 from the intermediate transfer body 11 when no image is being formed, and brings the primary transfer roller 10 into contact with the intermediate transfer body 11 when an image is being formed.

[0018] The server SV's arithmetic unit 301 includes one or more processors (CPUs) and performs various processes described below by executing control programs stored in the storage device 302. The storage device 302 includes any volatile and non-volatile storage devices. In addition to the programs executed by the arithmetic unit 301, the storage device 302 also stores data used by the arithmetic unit 301 in various processes. In this embodiment, the storage device 302 is a component of the server SV, but some or all of the data described below as being stored in the storage device 302 may be stored in an external device that the server SV can access via a network.

[0019] Figure 4 is a functional block diagram of this embodiment of the sound diagnostic system shown in Figure 3. The functional blocks shown in Figure 4 can be realized by the CPU 80 of the engine control unit 87 of the image forming apparatus PR and the CPU of the calculation unit 301 of the server SV executing their respective control programs.

[0020] When the receiving sound processing unit 70 receives a print job, it processes the sound signal received and output by the receiving unit 71 for a predetermined period of time, as described later. The receiving sound amplification unit 732 amplifies the sound signal from the receiving unit 71. The analog-to-digital (AD) conversion unit 733 converts the sound signal output by the receiving sound amplification unit 732 into a digital signal (digital value). Since the sound signal output by the receiving unit 71 includes a DC component, the reference value setting unit 734 subtracts a reference value from each value indicated by the digital signal from the AD conversion unit 733 to extract only the component related to sound pressure fluctuations. The reference value is set by the CPU 80.

[0021] The filter calculation unit 735 applies a filter to the digital signal from which the DC component has been removed from the reference value setting unit 734 to perform filtering. The filter calculation unit 735 has multiple filters and performs filtering using the filter set by the CPU 80. The squaring calculation unit 736 performs squaring of the digital signal after filtering. The interval averaging calculation unit 737 performs interval averaging of the digital signal after squaring. In this embodiment, as an example, the time interval for performing interval averaging is set to 100 ms. However, the time length for performing interval averaging is not limited to this and can be varied for each measurement. By performing squaring and interval averaging, a sound wave level L indicating the magnitude of sound pressure fluctuations for each time interval is obtained. The interval averaging calculation unit 737 stores the sound wave level L for each time interval in the sound information storage unit 738.

[0022] At this time, the status notification unit 731 determines the operating status of each motor 91-95 and solenoid 96, that is, whether or not they are operating, and associates the sound wave level L of the time interval with the operating status of each motor 91-95 and solenoid 96 in that time interval. In the following explanation, each motor 91-95 and solenoid 96 will be collectively referred to as "actuator". The sound information storage unit 738 stores information for each time interval indicating the operating status of each actuator in that time interval and the sound wave level L in that time interval. If the operating status of an actuator changes in the middle of a time interval, for example, the operating status with the longer operating time within the time interval will be used. Hereinafter, the information stored in the sound information storage unit 738, indicating the time interval, the operating status of each actuator in that time interval, and the sound wave level L in that time interval, will be referred to as sound data. Each sound data entry contains information indicating the operating state of each actuator and the sound wave level L for each of several consecutive time intervals. Furthermore, each sound data entry may be associated with print setting information such as the type of filter applied by the filter calculation unit 735 and the type (or basis weight) of the sheet S used for printing. In this manner, sound data is generated in the image forming apparatus PR in this embodiment. The sound information storage unit 738 transmits the sound data to the server SV. The server SV stores the sound data acquired from the image forming apparatus PR in the storage device 302.

[0023] The life count unit 739 counts the remaining life of components (replacement units) such as the cartridge 5, the intermediate transfer unit, each roller that transports the sheet, and the fixing unit 30. For example, the number of printable pages is set for each replacement unit. The life count unit 739 determines the remaining life such that the remaining life becomes 100% when the number of printable pages since the start of use of the replacement unit is 0, and the remaining life becomes 0% when the number of printable pages since the start of use of the replacement unit reaches the number of printable pages for that replacement unit. The life count unit 739 notifies the server SV of the remaining life of each replacement unit. The server SV stores the information indicating the remaining life of each replacement unit obtained from the image forming apparatus PR in the storage device 302.

[0024] Next, the processing performed by the server SV will be explained. The classification unit 3010 classifies and groups the sound data stored in the storage device 302. Grouping is performed based on the similarities and differences in the operating states of each actuator for each of the multiple time intervals of a single sound data. Specifically, multiple sound data sets with the same operating state of each actuator for each of the multiple time intervals are grouped into the same group. Grouping may also be performed based on the filter applied when the sound data was generated. In this case, for example, even if there are two sound data sets with the same operating state of each actuator for each of the multiple time intervals, if the filters applied when generating the two sound data sets are different, the two sound data sets will belong to different groups. Furthermore, grouping may also be performed based on print setting information. In this case, for example, even if there are two sound data sets with the same operating state of each actuator for each of the multiple time intervals, if the types of sheets S that were transported when acquiring the two sound data sets are different, the two sound data sets will belong to different groups.

[0025] As described later, the statistical value calculation unit 3011 calculates the statistical value P for each time interval for each group based on multiple sound data within the same group. Thus, the processes described below are performed independently for each group. Therefore, even if the term "per group" is omitted below, it means that the processes are performed independently for each group unless it is explicitly stated that they are not performed per group. As described later, the threshold setting unit 3012 sets the threshold TH-P for each time interval based on the statistical value P for each time interval. As described later, the determination unit 3013 uses the threshold TH-P for each time interval to determine whether or not an abnormal sound has occurred. Furthermore, if the determination unit 3013 determines that an abnormal sound has occurred, it determines the replacement unit that is generating the abnormal sound. The notification unit 3014 notifies the determination result made by the determination unit 3013. The notification recipient can be the host computer HC used by the user of the image forming apparatus PR or the dealer that performs maintenance and management of the image forming apparatus PR.

[0026] In this embodiment, one sound data is acquired during the period from when the last sheet S of the one or more sheets S on which an image is formed in a single print job reaches a predetermined position until after all actuators of the image forming apparatus PR have stopped. In this example, the timing when a sheet S reaches a predetermined position is defined as the timing when the rear end of the sheet S passes the detection position of the sheet S by the transport sensor 90. The length of the period for acquiring one sound data is set to 1600 ms. In this example, since the length of one time interval is 100 ms, one sound data is divided into 16 consecutive time intervals, and each time interval contains data indicating the sound wave level L and the operating state of each actuator.

[0027] The period from when the trailing edge of the last sheet S in a single print job passes the transport sensor 90 until all actuators of the image forming apparatus PR stop includes the period when the sheet S is not being transported near the receiving unit 71, and is a period during which the operating sounds of each actuator inside the image forming apparatus PR can be easily received. In the following description, the period from when the trailing edge of the last sheet S passes the transport sensor 90 until all actuators of the image forming apparatus PR stop will be referred to as the "post-rotation period". Note that the period for acquiring sound data is not limited to the above period and may include the period after the start of sheet feeding. Furthermore, if there is no need to reduce the load on the image forming apparatus PR for generating sound data or the processing load on the server SV due to the large amount of sound data, the period from the start of transport of each sheet S to its ejection can also be used as the acquisition period for one piece of sound data.

[0028] Figure 5 shows the threshold TH-P setting process performed by the server SV. When the classification unit 3010 acquires one sound data from the image forming apparatus PR, in S10 it determines the group to which the sound data belongs and stores the sound data in the storage device 302 in association with the group to which it belongs. As described above, grouping can be performed based on the differences in the operating state of each actuator over 16 time intervals. Furthermore, grouping can be performed based on the applied filter and print setting information. Figures 6(A) and 6(B) show two sound data that have been classified into different groups based on the operating state of each actuator. In Figures 6(A) and 6(B), "1" for each actuator indicates that the actuator is operating (operating state), and "0" indicates that it is not operating (non-operating state). The sound data shown in Figure 6(A) and the sound data shown in Figure 6(B) are grouped into different groups because the state of the actuators in the shaded areas is different.

[0029] When N new sound data are added to a group, the statistical value calculation unit 3011 calculates a statistical value P for each of the 16 time intervals based on these new N sound data in S11. The statistical value P can be, for example, the percentile value of the N sound data. For example, if N=100, the 95th percentile value can be used as the statistical value P. In this case, if the 16 time intervals for one sound data are designated as time interval #1 to time interval #16, the value of the 5th highest sound wave level L among the 100 sound wave levels L in time interval #1 becomes the statistical value P for time interval #1.

[0030] When the number of calculated statistical values ​​P reaches M, the threshold setting unit 3012 sets a threshold TH-P for each of the 16 time intervals based on the M statistical values ​​P in S12. The threshold TH-P can be, for example, a value obtained by adding a predetermined value to the average value of the M statistical values ​​P. As an example, M can be set to 100. Figure 7 shows the sound wave level L, the statistical value P obtained from the sound wave level L, and the threshold TH-P obtained from the statistical value P. In Figure 7, the threshold TH-P is set to a value 10 dB higher than the average value of the M statistical values ​​P. In this way, the threshold TH-P is obtained based on M × N sound wave levels L.

[0031] The method for calculating the statistical value P is not limited to the method described above. For example, the statistical value P can be any percentile value or the maximum value of N sound wave levels L. Furthermore, the statistical value P can be the average of the top predetermined number of N sound wave levels L. Similarly, the method for setting the threshold TH-P is not limited to the method described above. For example, the threshold TH-P can be the average or percentile value of M statistical values ​​P increased by a predetermined method.

[0032] Figures 8(A) to 8(C) all show examples of threshold TH-P set for the first time interval #1 of 16 time intervals. Note that the groups in Figures 8(A) to 8(C) are different. Specifically, Figure 8(A) is the group without any filter applied, Figure 8(B) is the group with a bandpass filter applied, and Figure 8(C) is the group with a high-pass filter applied.

[0033] Figure 9 is a flowchart of the process for determining whether an abnormal sound is occurring and which replacement unit is causing the abnormal sound. The process in Figure 9 is executed after the threshold TH-P for each of the 16 time intervals has been set. The classification unit 3010 groups the sound data each time sound data is input from the image forming apparatus PR, and the statistical value calculation unit 3011 calculates a statistical value P corresponding to each of the 16 time intervals each time N sound data is added to a group. The process in Figure 9 is executed when the statistical value calculation unit 3011 calculates a new statistical value P. The statistical value P in the process in Figure 9 is based on the sound data acquired by the server SV after the threshold TH-P has been set, and may be referred to as a "comparison value P" to distinguish it from the statistical value P used to determine the threshold TH-P.

[0034] In S20, the determination unit 3013 compares the statistical value P of each of the newly calculated 16 time intervals with the threshold TH-P of the corresponding time interval. The determination unit 3013 then determines that intervals in which the statistical value P is greater than or equal to the threshold TH-P are occurrence intervals where abnormal noise is occurring, and that the other intervals are non-occurrence intervals where abnormal noise is not occurring. In S21, the determination unit 3013 determines, based on the operating state of the actuator during the period when the noise changes from an occurrence interval to a non-occurrence interval, to be candidate replacement units that may be generating abnormal noise.

[0035] For example, suppose that the occurrence interval and non-occurrence interval are determined as shown in Figure 10. In Figure 10, "NG" indicates the occurrence interval and "OK" indicates the non-occurrence interval. In the results of Figure 10, the transition from the occurrence interval to the non-occurrence interval occurs from time interval #8 to time interval #9. The actuator that is in operation in time interval #8 and transitions to the non-operational state in time interval #9 is the solenoid 96. During the subsequent rotation period, the solenoid 96 operates to separate the primary transfer roller 10 from the intermediate transfer body 11. Therefore, it can be determined that the abnormal noise ceased to occur in time interval #9 because the primary transfer roller 10 separated from the intermediate transfer body 11. In this case, the intermediate transfer body unit, including the primary transfer roller 10 and the intermediate transfer body 11, is determined to be a candidate unit. The relationship between the actuator and the candidate unit that may be generating the abnormal noise is stored in advance in the server SV's storage device 302.

[0036] In S22, the determination unit 3013 determines whether or not a candidate unit has been identified. For example, if it is determined that no abnormal sound occurred in any time interval, no candidate unit is identified. If no candidate unit is identified, the determination unit 3013 terminates the process shown in Figure 9. On the other hand, if a candidate unit is identified, the determination unit 3013 determines in S23 whether or not there is only one candidate unit. For example, in the example shown in Figure 10, the only candidate unit is the intermediate transfer unit. If there is only one candidate unit, the determination unit 3013 causes the notification unit 3014 to notify in S24 that an abnormal sound has occurred and that this one candidate unit is the unit generating the abnormal sound.

[0037] On the other hand, if there are multiple candidate units, the determination unit 3013 proceeds to S25. For example, in Figure 10, suppose the status was NG until time interval #3, and changed to OK in time interval #4. In this case, the unit that stopped operating in time interval #4 is the feed motor 91. However, the feed motor 91 is the drive source for the feed roller 22, the transport roller 23, and the registration roller 25, and it is not possible to narrow it down to just one roller. Therefore, in S25, the determination unit 3013 refers to the remaining lifespan of each replacement unit received from the lifespan count unit 739. For example, if the remaining lifespan of the feed roller 22 is lower than the threshold, and the remaining lifespan of the other rollers is above the threshold, the determination unit 3013 determines in S25 that the feed roller 22 is generating an abnormal noise. In this way, if it is possible to narrow it down to one candidate unit in S25, the determination unit 3013 proceeds to S24. On the other hand, if the remaining lifespan does not narrow down the candidates to a single unit, the determination unit 3013 instructs the notification unit 3014 in S26 to notify that an abnormal sound has occurred and to identify each of the multiple candidate units that may be causing the abnormal sound. At this time, the configuration can also be configured to notify each of the multiple candidate units of, for example, the remaining lifespan and the probability (likelihood) that the abnormal sound is causing based on the remaining lifespan. In addition, if in S21 there are no actuators that are in an operating state during the occurrence interval and have changed to a non-operating state during the non-occurrence interval, the configuration can be configured to only notify in S24 that an abnormal sound has occurred.

[0038] As described above, according to this embodiment, a statistical value P of the sound wave level for each time interval is obtained from the sound data, and a threshold TH-P greater than the statistical value P is set based on this statistical value P. When a new statistical value P is obtained, the occurrence of an abnormal sound is determined by comparing it with the threshold TH-P. The operating state of the actuators in each time interval of the same group is the same, and by setting the threshold based on the sound wave level L when the operating state of the actuators is the same, the occurrence of an unknown abnormal sound can be detected with high accuracy. Furthermore, by determining whether or not an abnormal sound is occurring for each time interval, and determining the actuator whose operating state has changed at the timing when the occurrence or non-occurrence of an abnormal sound changes, it is possible to identify the replacement unit that is most likely to be generating the abnormal sound.

[0039] In the process shown in Figure 9, the occurrence of abnormal sound was determined by comparing a statistical value (comparison value) P for a time interval based on new sound data with the threshold value TH-P for that time interval. In this embodiment, the comparison value P was determined using the same method as the statistical value P used to determine the threshold value TH-P. However, the present invention is not limited to calculating the comparison value P using the same method as the statistical value P used to determine the threshold value TH-P. For example, the number of sound data used to determine the comparison value P can be different from the number of sound data N used to determine the statistical value P that forms the basis of the threshold value TH-P, for example, it can be reduced. Furthermore, the comparison value P can be the average value of the sound wave level L of multiple sound data instead of the percentile value. Furthermore, the comparison value P can be the sound wave level L of each time interval of a single sound data. In this case, when the server SV acquires one sound data from the image forming apparatus PR, it executes the process shown in Figure 9.

[0040] <Second Embodiment> Next, the second embodiment will be described, focusing on the differences from the first embodiment. Figure 11 is a flowchart of the threshold setting process according to this embodiment. When the classification unit 3010 acquires sound data from the image forming apparatus PR, in S30, similar to S10 in the first embodiment, it determines the group to which the sound data belongs and stores the sound data in the storage device 302 in association with the group to which it belongs. At this time, in S31, the classification unit 3010 determines the timing at which the operating state of each actuator changes, and calculates the difference value d of the actuator based on the sound wave level L of one or more time intervals before and after that timing and stores it in the storage device 302.

[0041] For example, in the case of the sound data in Figure 12, the feed motor 91 changes from an operating state to a non-operating state from time interval #3 to time interval #4. The intermediate transfer motor 92 changes from an operating state to a non-operating state from time interval #14 to time interval #15. The photoreceptor motor 93 changes from an operating state to a non-operating state from time interval #12 to time interval #13. The developing motor 94 changes from an operating state to a non-operating state from time interval #12 to time interval #13. The fixing motor 95 changes from an operating state to a non-operating state from time interval #10 to time interval #11. The solenoid 96 changes from an operating state to a non-operating state from time interval #8 to time interval #9. In this embodiment, the difference value d is obtained by subtracting the average value of the sound wave level L at the time of non-operation and the next two time intervals from the average value of the sound wave level L in the two time intervals that represent the operating state before becoming non-operating. The shaded areas in Figure 12 indicate the time intervals used to calculate the difference value d for each actuator.

[0042] In this embodiment, the difference value d is calculated based on two time intervals before the switch from the operating state to the non-operating state and two time intervals after the switch. However, it is also possible to calculate the difference value d based on one time interval immediately before the switch from the operating state to the non-operating state and one time interval immediately after the switch. Furthermore, it is also possible to use three or more time intervals. In addition, it is also possible to similarly calculate the difference value d for the timing of the switch from the non-operating state to the operating state.

[0043] When N new sound data are added to a group, the statistical value calculation unit 3011 calculates a statistical value D in S32 based on the N difference values ​​d obtained for each actuator. The statistical value D can be the 95th percentile value, similar to the statistical value P in the first embodiment. Subsequently, in S33, the statistical value calculation unit 3011 calculates a statistical value P for each time interval used to determine the difference value d for each actuator. For example, in Figure 12, time intervals #2 to #5 and #7 to #16 are used to determine the difference value d. Therefore, the statistical value P described in the first embodiment is obtained for each of the time intervals #2 to #5 and #7 to #16. In the following description, the time interval used to determine the difference value d of an actuator will be referred to as the time interval associated with that actuator. For example, in Figure 12, the time interval associated with the fixing motor 95 is time interval #9 to #12.

[0044] When the number of calculated statistical values ​​D and P reaches M, the threshold setting unit 3012 sets the threshold TH-D in S34 based on the M statistical values ​​D for each actuator. The method for calculating the threshold TH-D is the same as the method for calculating the threshold TH-P in the first embodiment. Furthermore, for each time interval in which the statistical values ​​P were calculated, the threshold setting unit 3012 sets the threshold TH-P based on the M statistical values ​​P. The method for calculating the threshold TH-P is the same as in the first embodiment.

[0045] Figure 13 is a flowchart of the process for determining whether or not an abnormal sound is occurring and which replacement unit is causing the abnormal sound. The process in Figure 13 is executed after thresholds TH-P and TH-D are set. The classification unit 3010 groups the sound data each time sound data is input from the image forming apparatus PR, and the statistical value calculation unit 3011 calculates statistical values ​​D and P each time N sound data are added to a group. The process in Figure 13 is executed when the statistical value calculation unit 3011 calculates new statistical values ​​P and D. As in the first embodiment, the statistical values ​​D and P in the process in Figure 13 are based on the sound data acquired by the server SV after thresholds TH-D and TH-P are set. Therefore, to distinguish them from the statistical values ​​D and P used to determine thresholds TH-D and TH-P, they may also be referred to as "comparison values ​​D" and "comparison values ​​P".

[0046] In S40, the determination unit 3013 compares the newly calculated actuator's statistical value D with the actuator's threshold TH-D. The determination unit 3013 then determines which actuators have a statistical value D equal to or greater than the threshold TH-D. In S41, for each actuator whose statistical value D was equal to or greater than the threshold TH-D, the determination unit 3013 compares the statistical value P of the time interval associated with the actuator with the threshold TH-P.

[0047] For example, suppose that among the actuators shown in Figure 12, the statistical value D of the fixing motor 95 is greater than or equal to the threshold TH-D of the fixing motor 95, and the statistical value D of each of the other actuators is less than the corresponding threshold TH-D. In this case, in S41, the determination unit 3013 compares the statistical value P with the threshold TH-P for each of the time intervals #9 to #12 associated with the fixing motor 95. If the statistical value P is greater than or equal to the threshold TH-P in time intervals #9 and #10 when the fixing motor 95 was operating, the determination unit 3013 determines that an abnormal noise has occurred. Furthermore, the determination unit 3013 determines whether the statistical value P is less than the threshold TH-P in time intervals #11 and #12 when the fixing motor 95 was not operating. In other words, it determines whether the abnormal noise has stopped when the fixing motor 95 is not operating. If an abnormal noise occurs when the fuser motor 95 is operating, and the abnormal noise stops when the fuser motor 95 is deactivated, the determination unit 3013 determines that the fuser unit 30 driven by the fuser motor 95 is a candidate unit. Subsequently, the determination unit 3013 performs the processing in S22 to S26, as in the first embodiment. Note that if an abnormal noise is still present even when the fuser motor 95 is deactivated, the system can be configured to only notify the occurrence of the abnormal noise in S24.

[0048] According to this embodiment, for each actuator, a statistical value D is calculated based on the difference in sound wave level L before and after the actuator's state changes, and a threshold TH-D greater than this statistical value D is set. Then, for each actuator, once a new statistical value D is obtained, it is compared with the threshold TH-D to first narrow down the actuators that may be associated with the occurrence of abnormal noise. Then, for the time interval associated with the actuator, the occurrence of abnormal noise is determined by comparing the statistical value P with the threshold TH-P, similar to the method in the first embodiment. Here, if abnormal noise occurs when the actuator is operating and does not occur when the actuator is not operating, the replacement unit associated with that actuator is determined to be a candidate unit that may be generating the abnormal noise. With this configuration, even for unknown abnormal noises, it is possible to determine whether or not abnormal noise is occurring and which candidate unit may be generating the abnormal noise.

[0049] In the process shown in Figure 13, actuators were narrowed down in S40, and the occurrence of abnormal noise and candidate units were determined in S41. However, it is also possible to configure the system so that in S40, if there is an actuator whose statistical value D is greater than or equal to the threshold TH-D, it is determined that an abnormal noise has occurred, and the unit associated with that actuator is determined to be a candidate unit. In this case, the process in S41 is omitted.

[0050] Furthermore, in the processing shown in Figure 13, the statistical values ​​(comparison values) D and P for the time interval based on the new sound data were obtained using the same method as the statistical values ​​D and P used to determine the thresholds TH-D and TH-P. However, as in the first embodiment, the comparison values ​​D and P can be configured to be obtained using a different method than the statistical values ​​D and P. For example, the comparison value P can be obtained as described in the first embodiment. Also, the number of sound data used to obtain the comparison value D can be different from the number of sound data N used to obtain the statistical value D that forms the basis of the threshold TH-D; for example, it can be reduced. Furthermore, the comparison value D can be the average value of multiple difference values ​​d instead of the percentile value. Furthermore, the comparison value D can be the difference value d obtained from a single sound data. In this case, when the server SV obtains one sound data from the image forming apparatus PR, it executes the processing shown in Figure 13.

[0051] <Other> In the embodiments described above, the classification unit 3010 classified and grouped sound data based on the similarities and differences in the operating states of multiple actuators in each of the multiple time intervals of a single sound data. However, it is also possible to configure the system to classify and group sound data based on the similarities and differences in the operating states of a single actuator in each time interval. For example, if the system is grouped based only on the operating state of the feed motor 91, the sound data in Figure 6(A) and the sound data in Figure 6(B) will belong to the same group. Also, if the system is grouped based only on the operating state of the solenoid 96, the sound data in Figure 6(A) and the sound data in Figure 6(B) will belong to different groups. Therefore, the present invention can be configured to classify and group sound data based on the similarities and differences in the operating states of one or more actuators in each of the multiple time intervals of a single sound data.

[0052] Furthermore, in each of the above embodiments, the classification unit 3010 grouped sound data into multiple groups based on the operating state of the actuator. The threshold setting unit 3012 then set thresholds for each of the multiple time intervals for each of the multiple groups. In addition, the determination unit 3013 determined whether or not an abnormal sound was occurring by obtaining comparison values ​​for each of the multiple time intervals for each of the multiple groups and comparing the comparison values ​​for each of the multiple time intervals with the thresholds for the corresponding time intervals of the same group. However, it is also possible to configure the system so that the threshold setting unit 3012 sets thresholds for each of the multiple time intervals for one of the multiple groups, and the determination unit 3013 determines whether or not an abnormal sound is occurring by obtaining comparison values ​​based on the sound data of that one group for which thresholds have been set.

[0053] Furthermore, the processing described as being performed on the server SV can also be configured to be performed on the engine control unit 87 of the image forming apparatus PR. In addition, some of the processing performed by the received sound processing unit 70, for example, the processing performed by the functional blocks from the reference value setting unit 734 onward, i.e., the sound data generation processing, can also be configured to be performed on the server SV. In this case, the image forming apparatus PR transmits the digital signal output by the AD conversion unit 733 to the server SV along with information indicating the operating status of each actuator.

[0054] Furthermore, the sound diagnostic systems of each of the above embodiments were used to determine whether or not abnormal sounds were being generated in the image forming apparatus PR. However, the sound diagnostic system of the present invention is not limited to determining whether or not abnormal sounds are being generated in the image forming apparatus PR. Specifically, it can determine whether or not abnormal sounds are being generated in a device having one or more actuators.

[0055] [Other embodiments] The present invention can also be realized by supplying a program that implements one or more of the functions of the above-described embodiments to a system or device via a network or storage medium, and by having one or more processors in the computer of that system or device read and execute the program. It can also be realized by a circuit (e.g., an ASIC) that implements one or more functions.

[0056] The invention is not limited to the embodiments described above, and various modifications and variations are possible without departing from the spirit and scope of the invention. Accordingly, claims are attached to disclose the scope of the invention. [Explanation of Symbols]

[0057] 71: Receiving unit, 70: Receiving sound processing unit, 731: Status notification unit, 3010: Classification unit, 3011: Statistical value calculation unit, 3012: Threshold setting unit, 3013: Judgment unit

Claims

1. A receiving means for receiving sound waves in a device having one or more actuators, A control means, The receiving means processes the signal indicating sound waves for a predetermined period, and generates sound data indicating the sound wave level for each of the multiple time intervals into which the predetermined period is divided, and the operating state of one or more actuators for each of the multiple time intervals. Based on the difference in the operating state of one or more actuators in each of the aforementioned multiple time intervals, the sound data is classified into multiple groups, including the first group. The threshold for each of the plurality of time intervals is generated using the sound wave levels of each of the plurality of time intervals of the plurality of first sound data classified into the first group, Based on the sound wave levels of each of the multiple time intervals of one or more second sound data classified into the first group, a comparison value is obtained for each of the multiple time intervals. The control means determines whether the comparison value for each of the plurality of time intervals is greater than the threshold value for the corresponding time interval of the first group, A sound diagnostic system equipped with this feature.

2. The sound diagnostic system according to claim 1, wherein the control means determines that an abnormal sound is occurring in a time interval in which the comparison value is greater than the threshold value.

3. The sound diagnostic system according to claim 2, wherein the control means determines from the one or more actuators which operate in a time interval in which it is determined that an abnormal sound is occurring and which does not operate in a time interval in which it is determined that no abnormal sound is occurring, based on the operating state of one or more actuators associated with the sound data classified into the first group, and determines the unit of the device that is generating the abnormal sound based on the first actuator.

4. The aforementioned comparison value is the first comparison value, The aforementioned threshold is the first threshold, The aforementioned multiple groups include a second group, The control means is The second threshold for each of the aforementioned multiple time intervals is generated using the sound wave levels of each of the multiple time intervals of the multiple third sound data classified into the second group, Based on the sound wave levels of each of the multiple time intervals of one or more fourth sound data classified into the second group, a second comparison value is obtained for each of the multiple time intervals. The sound diagnostic system according to any one of claims 1 to 3, which determines whether the second comparison value for each of the plurality of time intervals is greater than the second threshold value for the corresponding time interval of the second group.

5. A receiving means for receiving sound waves in a device having one or more actuators, A control means, The receiving means processes the signal indicating sound waves for a predetermined period, and generates sound data indicating the sound wave level for each of the multiple time intervals into which the predetermined period is divided, and the operating state of one or more actuators for each of the multiple time intervals. Based on the difference in the operating state of one or more actuators in each of the aforementioned multiple time intervals, the sound data is classified into multiple groups, including a first group. For each of the one or more actuators, a first threshold value is generated for the actuator based on the difference between the sound wave levels of one or more first time intervals in which the actuator is operating, associated with the plurality of first sound data classified in the first group, and the sound wave levels of one or more second time intervals in which the actuator is not operating, associated with the plurality of first sound data classified in the first group. Based on the difference between the sound wave levels of one or more first time intervals associated with the actuator for one or more second sound data classified in the first group and the sound wave levels of one or more second time intervals associated with the actuator for one or more second sound data classified in the first group, the comparison value of the actuator is determined. The control means determines whether the comparison value of each of the one or more actuators is greater than the first threshold of the corresponding actuator. A sound diagnostic system equipped with this feature.

6. The sound diagnostic system according to claim 5, wherein the control means determines that an abnormal sound is occurring if there is a first actuator whose comparison value is greater than the first threshold.

7. The control means further, The second threshold for each of the one or more first time intervals is generated using the sound wave levels of each of the one or more first time intervals of the plurality of first sound data. If there is a first actuator whose comparison value is greater than the first threshold, the first comparison value for each of the one or more first time intervals associated with the first actuator is determined based on the sound wave level of each of the one or more first time intervals associated with the first actuator of the one or more second sound data. The first comparison value for each of the one or more first time intervals associated with the first actuator is compared with the second threshold value for the corresponding first time interval. The sound diagnostic system according to claim 5, wherein if the first comparison value for each of the one or more first time intervals associated with the first actuator is greater than the second threshold value for the corresponding first time interval, it is determined that an abnormal sound is occurring.

8. The control means is The third threshold for each of the one or more second time intervals is generated based on the sound wave levels of each of the one or more second time intervals of the plurality of first sound data. If the first comparison value for each of the one or more first time intervals associated with the first actuator is greater than the second threshold for the corresponding first time interval, then the second comparison value for each of the one or more second time intervals associated with the first actuator is determined based on the sound wave levels of each of the one or more second time intervals associated with the first actuator of the one or more second sound data. The second comparison value for each of the one or more second time intervals associated with the first actuator is compared with the third threshold value for the corresponding second time interval. The sound diagnostic system according to claim 7, wherein if the second comparison value for each of the one or more second time intervals associated with the first actuator is smaller than the third threshold value for the corresponding second time interval, the unit of the device generating the abnormal sound is determined based on the first actuator.

9. The sound diagnostic system according to any one of claims 5 to 8, wherein, for each of the one or more actuators, the one or more first time intervals and the one or more second time intervals of the actuator are consecutive time intervals.

10. The control means is The remaining lifespan of each unit of the aforementioned device is managed, The sound diagnostic system according to claim 3 or 8, wherein, if multiple units are determined based on the first actuator, the unit of the device that is generating the abnormal sound is determined based on the remaining lifespan of each of the multiple units.

11. The sound diagnosis system according to any one of claims 1 to 10, wherein the one or more second sound data are sound data generated after the plurality of first sound data.

12. The aforementioned one or more second-tone data are multiple second-tone data, The sound diagnostic system according to any one of claims 1 to 4, wherein the comparison value is the percentile value of the sound wave level for each time interval of the plurality of second sound data.

13. The control means further In order to generate the aforementioned sound data, a filter is applied to the signal representing the sound waves for the predetermined period received by the receiving means. The sound diagnostic system according to any one of claims 1 to 12, further classifying the sound data based on the type of filter applied to generate the sound data.

14. The aforementioned apparatus is an image forming apparatus that forms an image on a conveyed sheet, The predetermined period includes the period during which the image forming apparatus is operating to form an image on the sheet. The sound diagnostic system according to any one of claims 1 to 13, wherein the control means further classifies the sound data based on the type of sheet.

15. The sound diagnostic system according to claim 14, wherein the predetermined period includes the period from the time when the last of the one or more sheets reaches a predetermined position in the image forming apparatus until the one or more actuators stop operating, during the period in which the image forming apparatus is operating to form an image on one or more sheets.

16. The receiving means is provided in the image forming apparatus, The sound data is generated in the image forming apparatus, The sound diagnostic system according to claim 14 or 15, wherein the determination of whether the comparison value is greater than the threshold is performed in an information processing device that communicates with the image forming apparatus.

17. The receiving means is provided in the image forming apparatus, The sound data is generated in an information processing device that communicates with the image forming apparatus. The sound diagnostic system according to claim 14 or 15, wherein the determination of whether the comparison value is greater than the threshold is performed in the information processing device.

18. The receiving means is provided in the image forming apparatus, The sound data is generated in the image forming apparatus, The sound diagnostic system according to claim 14 or 15, wherein the determination of whether the comparison value is greater than the threshold is performed in the image forming apparatus.

19. In a device having one or more actuators, sound data is acquired that is generated based on a signal indicating sound waves received by a receiving means over a predetermined period, and that indicates the sound wave level for each of a plurality of time intervals into which the predetermined period is divided, and the operating state of the one or more actuators for each of the plurality of time intervals. Based on the difference in the operating state of one or more actuators in each of the multiple time intervals of the sound data, the sound data is classified into multiple groups, including a first group. The threshold for each of the plurality of time intervals is generated using the sound wave levels of each of the plurality of time intervals of the plurality of first sound data classified into the first group, Based on the sound wave levels of each of the multiple time intervals of one or more second sound data classified into the first group, a comparison value is obtained for each of the multiple time intervals. Control means for determining whether the comparison value of each of the plurality of time intervals is greater than the threshold value of the corresponding time interval of the first group, An information processing device equipped with the following features.

20. In a device having one or more actuators, sound data is acquired that is generated based on a signal indicating sound waves received by a receiving means over a predetermined period, and that indicates the sound wave level for each of a plurality of time intervals into which the predetermined period is divided, and the operating state of the one or more actuators for each of the plurality of time intervals. Based on the difference in the operating state of one or more actuators in each of the multiple time intervals of the sound data, the sound data is classified into multiple groups, including a first group. For each of the one or more actuators, a first threshold value for the actuator is generated based on the difference between the sound wave level of one or more first time intervals in which the actuator is operating, associated with the plurality of first sound data classified into the first group, and the sound wave level of one or more second time intervals in which the actuator is not operating, associated with the plurality of first sound data classified into the first group. Based on the difference between the sound wave levels of one or more first time intervals associated with the actuator for one or more second sound data classified in the first group and the sound wave levels of one or more second time intervals associated with the actuator for one or more second sound data classified in the first group, the comparison value of the actuator is determined. Control means for determining whether the comparison value of each of the one or more actuators is greater than the first threshold of the corresponding actuator. An information processing device equipped with the following features.

21. A program that causes a computer to function as an information processing device according to claim 19 or 20.