JP7790328B2 - Abnormal noise diagnosis device - Google Patents

Description

This disclosure relates to an abnormal noise diagnosis device that diagnoses abnormal noises generated in a vehicle.

A sound and vibration analyzer is known that, when the power transmission mechanism of a vehicle having multiple rotating bodies is in operation, collects and analyzes data on the sound or vibration generated by the rotation of the rotating bodies and data on the rotation speed of selected rotating bodies (see, for example, Patent Document 1). This sound and vibration analyzer performs frequency analysis on the sound or vibration data and calculates an order based on the specifications of the rotating body from the frequency-analyzed sound or vibration data. Furthermore, the sound and vibration analyzer displays on a display unit the sound pressure level calculated from the sound or vibration data in correspondence with the order and vehicle speed, and plays back on the display unit a sound having a specific order selected by the operator.

Japanese Patent Application Laid-Open No. 2005-98984

In vehicles that include a manual transmission connected to an internal combustion engine via a clutch, abnormal noise may occur when the clutch is partially engaged (during partial clutch engagement) due to resonance between components of the clutch and components of the manual transmission. However, even when examining the order of the noise according to the frequency and specifications of the rotating body, it is difficult to determine whether abnormal noise occurring during partial clutch engagement is caused by resonance between components of the clutch and components of the manual transmission.

The primary objective of this disclosure is to accurately determine whether abnormal noise generated when the clutch between the internal combustion engine and the manual transmission is partially engaged is caused by resonance between the components of the clutch and the components of the manual transmission.

The abnormal noise diagnosis device disclosed herein is an abnormal noise diagnosis device that diagnoses abnormal noise generated in a vehicle that includes an internal combustion engine, a clutch, and a manual transmission connected to the internal combustion engine via the clutch. If the frequency of abnormal noise generated while the clutch is partially engaged falls within a predetermined frequency range corresponding to the combination of the clutch and the manual transmission, and the clutch transmission torque transmitted by the clutch when the abnormal noise occurs falls within a predetermined torque range corresponding to the combination of the clutch and the manual transmission, the device diagnoses that abnormal noise caused by resonance between components of the clutch and components of the manual transmission has occurred while the clutch is partially engaged.

This abnormal noise diagnosis device makes it possible to accurately determine whether abnormal noise occurring when the clutch between the internal combustion engine and the manual transmission is partially engaged is caused by resonance between the clutch components and the manual transmission components. Furthermore, the abnormal noise diagnosis device disclosed herein may include a diagnosis unit constructed using machine learning to diagnose the cause of the abnormal noise based on provided information when it is determined that abnormal noise caused by resonance between the clutch components and the manual transmission components is not occurring when the clutch is partially engaged.

1 is a schematic configuration diagram illustrating an abnormal sound diagnosis system including an abnormal sound diagnosis device according to the present disclosure. 3 is a flowchart showing a series of processes executed by the abnormal sound diagnosis device of the present disclosure. 1 is a diagram illustrating an example of the relationship between the frequency of an abnormal noise generated due to resonance between a component of the clutch and a component of a manual transmission when the clutch is partially engaged, and the clutch transmission torque transmitted by the clutch when the abnormal noise is generated.

Next, we will explain the form for implementing the invention of this disclosure with reference to the drawings.

Figure 1 is a schematic diagram showing an abnormal sound diagnosis system 1 including a server 20 as the abnormal sound diagnosis device of the present disclosure. The abnormal sound diagnosis system 1 shown in the figure is used to diagnose the cause of abnormal sounds generated in various vehicles, including a vehicle X equipped with a manual transmission MT. In addition to the manual transmission MT, the vehicle X includes an internal combustion engine EG and a clutch C interposed between the internal combustion engine and the manual transmission MT.

As shown in FIG. 1, the abnormal sound diagnosis system 1 includes a server 20 and a mobile terminal 10 capable of exchanging information with the server 20 via communication. The mobile terminal 10 is used by a worker (user of the abnormal sound diagnosis system 1) at a vehicle dealership, repair shop, or the like when responding to a user (owner) of a vehicle X or the like that is experiencing an abnormal sound, or when performing a reproduction test in which the vehicle X or the like is driven (operated) on a roadway or test bench to reproduce the abnormal sound. In this embodiment, the mobile terminal 10 is a smartphone that includes an SoC, ROM, RAM, an auxiliary storage device (flash memory) M, a touch-panel display 11, a communication module 12 capable of exchanging various information with the server 20 or an electronic control unit (ECU) (not shown) of the vehicle X or the like via wired or wireless communication, and a microphone (not shown). An abnormal sound diagnosis support application (program) is also installed on the mobile terminal 10. As shown in FIG. 1, the mobile terminal 10 includes a medical interview information acquisition unit 13, a sound acquisition unit 14, a vehicle state acquisition unit 15, a calculation processing unit 16, an extraction unit 17, and a display control unit 18, which are constructed in cooperation with an abnormal sound diagnosis support application (software) and hardware such as the SoC of the mobile terminal 10.

The medical interview information acquisition unit 13 acquires, via the display unit 11, medical interview information indicating the state of vehicle X or the like at the time of the occurrence of an abnormal noise, provided by the user of vehicle X or the like. The medical interview information includes vehicle identification information, including the vehicle model and vehicle identification number (chassis number), the order, the date and time of occurrence, the frequency of occurrence, the location of the abnormal noise, the type of sound (onomatopoeia), physical quantities that change while vehicle X or the like is traveling, the operating state of vehicle X or the like, the warm-up effect of an engine-equipped vehicle, options selected by the driver while driving vehicle X or the like, and driving environment information of vehicle X or the like, and is input by the operator or the user of vehicle X or the like. The sound acquisition unit 14 acquires time axis data of sound (sound pressure) when the operator performs a reproduction test. The vehicle state acquisition unit 15 acquires vehicle state data indicating the state of vehicle X or the like in synchronization with the acquisition of the time axis data of sound by the sound acquisition unit 14 when the reproduction test is performed. The vehicle state data includes multiple physical quantities corresponding to items of the medical interview information, such as vehicle speed, acceleration, road gradient of the road surface, and gear position of the manual transmission MT. The calculation processing unit 16 performs analysis processing of the time axis data of the sound acquired by the sound acquisition unit 14. The extraction unit 17 performs narrowing down of the analysis results by the calculation processing unit 16 in accordance with the selection of the operator, etc. The display control unit 18 controls the display unit 11.

The server 20, which serves as an abnormal sound diagnosis device, is a computer including a CPU, ROM, RAM, input/output devices, a communications module, etc., and is installed and managed, for example, by the automobile manufacturer that produces the vehicle X, etc. The server 20 is configured with an abnormal sound diagnosis unit 21 that diagnoses abnormal sounds generated in the vehicle X, etc., through cooperation between hardware such as the CPU and a pre-installed abnormal sound diagnosis application. The abnormal sound diagnosis unit 21 includes a neural network (convolutional neural network) as a diagnostic module constructed using supervised learning (machine learning) to diagnose the cause of abnormal sounds generated in the vehicle X, etc., and the part that is the source of the abnormal sound, based on the medical interview information and sound time axis data acquired by the mobile terminal 10.

When the server 20 detects the occurrence of a new abnormal noise in vehicle X or the like, it executes re-learning in the abnormal noise diagnosis unit 21, using the acquired sound time axis data for the new abnormal noise and the details of each item of the medical interview information as training data. The server 20 also includes a storage device 22 that stores an abnormal noise database containing information on multiple abnormal noises known to occur in each vehicle model. The abnormal noise database associates each of the multiple abnormal noises with information such as the sound time axis data, the cause of the abnormal noise, the part that is the source of the noise, the details of the medical interview information provided by the user or the like, and measures to resolve the abnormal noise. The server 20 also updates the abnormal noise database based on information acquired from vehicle X or the like, and information (reports) related to newly discovered abnormal noises sent from the automobile manufacturer (developer, etc.), vehicle dealership, repair shop, etc.

Next, the procedure for diagnosing an abnormal noise generated in a vehicle X or the like using the abnormal noise diagnosis system 1 will be described. When a user of a vehicle X or the like requests the diagnosis of an abnormal noise, a worker at a vehicle dealership or the like listens to the user's medical history and then performs a reproduction test to obtain the information necessary to diagnose the abnormal noise. To perform the reproduction test, the worker connects the mobile terminal 10 to the electronic control device of the vehicle X or the like, and places (fixes) the mobile terminal 10 or an external microphone connected to the mobile terminal 10 in an appropriate location of the vehicle X or the like (e.g., the passenger compartment or engine compartment). The worker also launches the abnormal noise diagnosis support application and turns on the start switch of the vehicle X or the like. Accordingly, the mobile terminal 10 obtains information such as the vehicle identification number or chassis number of the vehicle X or the like from the electronic control device. The worker then taps the recording start button displayed on the display unit 11 and drives (operates) the vehicle X or the like on a roadway or test stand to reproduce the driving conditions under which the abnormal noise occurred based on the medical history information from the user of the vehicle X or the like.

While vehicle X or the like is traveling (operating), the sound acquisition unit 14 of the mobile terminal 10 acquires time axis data of sound emitted from vehicle X or the like at predetermined time intervals (micro-time intervals) and stores the data in the auxiliary storage device M. In addition, the vehicle state acquisition unit 15 acquires vehicle state data specified by the worker in accordance with the medical interview information from the electronic control device of vehicle X or the like at predetermined time intervals (micro-time intervals) in synchronization with the acquisition of the sound time axis data by the sound acquisition unit 14, and stores the data in the auxiliary storage device M. When the worker taps the recording stop button displayed on the display unit 11, the acquisition of the sound time axis data and vehicle state data is completed.

After the reproduction test is completed, the calculation processing unit 16 performs a Short-Time Fourier Transform (STFT) on the sound time-axis data to obtain a spectrogram (acoustic spectrogram) showing the relationship between time, frequency, and sound pressure. The display control unit 18 then displays the spectrogram on the display unit 11. In this embodiment, the spectrogram is a color map with the horizontal axis representing time and the vertical axis representing frequency, and color-codes sound pressure levels to show the relationship between time and sound pressure level for each frequency. The operator also selects (specifies) on the display unit 11 the range of the spectrogram to be diagnosed (analyzed) by the abnormal sound diagnosis unit 21 (server 20) (hereinafter referred to as the "diagnosis range"). The operator then enters medical interview information into the input screen displayed on the display unit 11. When the operator taps the information transmission button displayed on the display unit 11, the information necessary for diagnosing the abnormal sound is transmitted from the communication module 12 of the mobile terminal 10 to the server 20. In this embodiment, the information sent from the mobile terminal 10 to the server 20 includes time axis data of the sound acquired by the sound acquisition unit 14, vehicle condition data acquired by the vehicle condition acquisition unit 15, medical interview information, and information defining the above-mentioned diagnostic range.

2 is a flowchart showing a series of processes executed by the server 20 in response to receiving information from the mobile device 10. As shown in the figure, the abnormal sound diagnosis unit 21 of the server 20 acquires sound time axis data, vehicle condition data, medical history information, and information defining the diagnosis range from the mobile device 10 (S100). The abnormal sound diagnosis unit 21 then determines whether the target vehicle is equipped with a manual transmission MT based on the vehicle identification number, etc., included in the medical history information (S110). If the target vehicle is equipped with a manual transmission MT (S110: YES), the abnormal sound diagnosis unit 21 determines whether the abnormal sound occurred while the clutch C was partially engaged (half-clutch engaged) based on the operating state of the vehicle X included in the medical history information (S120). If the abnormal sound occurred while the clutch C was partially engaged (S120: YES), the abnormal sound diagnosis unit 21 acquires the frequency fc of the abnormal sound generated while the clutch C was partially engaged from the sound time axis data acquired in step S100 (S130). In step S130, the abnormal sound diagnosis unit 21 extracts characteristic frequencies in the diagnosis range selected by the operator according to a predetermined procedure, and sets the extracted frequencies as the frequency fc of the abnormal sound.

Next, the abnormal sound diagnosis unit 21 obtains the vehicle speed V (km/h), acceleration a (m/ ^s2 ), road surface gradient θ (deg), and gear position of the manual transmission MT of the vehicle X within the diagnosis range selected by the operator from the vehicle condition data obtained in step S100, and calculates the clutch transmission torque Tc, which is the average value within the diagnosis range of the torque T transmitted by the clutch C when an abnormal sound is generated, obtained from the following equation (1) (S140). In equation (1), "M" is the weight (kg) of the vehicle X, "G" is the acceleration due to gravity, "Ffrict" is the running resistance obtained from a predetermined function of the vehicle speed V, "r" is the tire radius (m), and "itotal" is the product of the gear ratio of the gear position of the manual transmission MT when the clutch C is partially engaged and the final gear ratio of the differential gear. Furthermore, the weight M, the function for deriving the running resistance Ffrict, and the tire radius r are obtained from the vehicle information database stored in the storage device 22 or another server, and correspond to the vehicle identification number, etc.

T=(M・a+M・G・sinθ+Ffrict)×r/itotal…(1)

Furthermore, the abnormal noise diagnosis unit 21 obtains the model of the clutch C and the model of the manual transmission MT installed in the vehicle X from the vehicle information database based on the vehicle identification number, etc., included in the medical interview information, and reads the abnormal noise occurrence conditions corresponding to the combination of the clutch C (model) and the manual transmission MT (model) from the storage device 22 (S150). The inventor conducted extensive research into abnormal noise that occurs when the clutch C is partially engaged in a vehicle X including a manual transmission MT, and as a result, found that the frequency of the abnormal noise generated due to resonance between the friction plate (component) of the clutch C and the input shaft (component) of the manual transmission MT when the clutch C is partially engaged, and the torque transmitted by the clutch C when the abnormal noise occurs, fall within a frequency range and torque range (see dashed lines in the figure) determined for each combination of the clutch C and the manual transmission MT, as shown in Figure 3. Based on this, in this embodiment, for each of a plurality of combinations of clutch C and manual transmission MT, abnormal noise occurrence conditions that define the frequency range and torque range of abnormal noise caused by resonance between the friction plates of the clutch C and the input shaft of the manual transmission MT are determined in advance through experiments and analysis, and are stored in the storage device 22 (abnormal noise database) of the server 20.

The abnormal sound diagnosis unit 21 then determines whether the abnormal sound frequency fc obtained in step S130 is within the frequency range of the abnormal sound generation conditions corresponding to the combination of the clutch C and the manual transmission MT, and whether the clutch transmission torque Tc calculated in step S140 is within the torque range of the abnormal sound generation conditions corresponding to the combination of the clutch C and the manual transmission MT (S160). If the frequency fc is within the frequency range of the abnormal sound generation conditions and the clutch transmission torque Tc is within the torque range of the abnormal sound generation conditions (S160: YES), the abnormal sound diagnosis unit 21 diagnoses (determines) that the abnormal sound generated in the vehicle X is caused by resonance between the friction plates of the clutch C and the input shaft of the manual transmission MT while the clutch C is partially engaged (S170). On the other hand, if the target vehicle is not equipped with a manual transmission MT (S110: NO), if the abnormal noise does not occur while the clutch C is partially engaged (S120: NO), or if at least one of the frequency fc and the clutch transmission torque Tc is not within the frequency range or torque range for the abnormal noise occurrence conditions (S160: NO), the abnormal noise diagnosis unit 21 will diagnose the cause of the abnormal noise occurring in vehicle X, etc. using the neural network based on the information acquired in step S100 (S115).

After processing step S170 or step S115, the abnormal sound diagnosis unit 21 creates a diagnosis result that includes the name of the abnormal sound, the part that is the source of the abnormal sound, the cause of the abnormal sound, and measures to eliminate the abnormal sound that are read from the storage device 22 (S180). Furthermore, the abnormal sound diagnosis unit 21 sends the diagnosis result created in step S180 to the mobile device 10 (S190), ending the series of processes in FIG. 2. When the diagnosis result from the server 20 is received by the mobile device 10, the diagnosis result is displayed on the display unit 11. This allows the worker to accurately explain the diagnosis result from the server 20 to the user of vehicle X, etc., and promptly proceed with measures to address the abnormal sound.

As explained above, the server 20, which serves as the abnormal sound diagnosis device in the abnormal sound diagnosis system 1, diagnoses that abnormal sound caused by resonance between components of the clutch C and the manual transmission MT has occurred while the clutch C is partially engaged (during partial clutch engagement) if the frequency fc of the abnormal sound generated while the clutch C is partially engaged falls within the frequency range corresponding to the combination of the clutch C and the manual transmission MT, and the clutch transmission torque Tc transmitted by the clutch C at the time the abnormal sound is generated falls within the torque range corresponding to the combination of the clutch C and the manual transmission MT (S100-S170). This makes it possible to accurately determine whether abnormal sound generated while the clutch C between the internal combustion engine EG and the manual transmission MT is partially engaged is caused by resonance between components of the clutch C and the manual transmission MT.

The server 20 also includes an abnormal sound diagnosis unit 21 that is constructed using machine learning to diagnose the cause of the abnormal sound based on provided information when it is determined that the abnormal sound caused by resonance between components of the clutch C and components of the manual transmission MT is not occurring while the clutch C is partially engaged. This further improves the versatility of the server 20 and, ultimately, the abnormal sound diagnosis system 1 that includes the server 20. The abnormal sound diagnosis support application installed on the mobile terminal 10 may also be installed on a tablet terminal or personal computer, and the tablet terminal may be used in place of the mobile terminal 10. Furthermore, some of the functions of the abnormal sound diagnosis unit 21 may be provided on the mobile terminal 10, and the abnormal sound diagnosis system 1 may be configured as a single information processing device such as a personal computer.

The disclosed invention is extremely useful for diagnosing abnormal noises occurring in vehicles that include manual transmissions.

1 Abnormal sound diagnosis system, 10 Mobile terminal, 20 Server (abnormal sound diagnosis device), 21 Abnormal sound diagnosis unit, C Clutch, EG Internal combustion engine, MT Manual transmission, X Vehicle.

Claims (1)

An abnormal noise diagnosis device for diagnosing an abnormal noise generated in a vehicle including an internal combustion engine, a clutch, and a manual transmission connected to the internal combustion engine via the clutch,
An abnormal noise diagnosis device that diagnoses that abnormal noise caused by resonance between components of the clutch and components of the manual transmission has occurred while the clutch is partially engaged, if the frequency of the abnormal noise occurred while the clutch is partially engaged is within a predetermined frequency range corresponding to the combination of the clutch and the manual transmission, and if the clutch transmission torque transmitted by the clutch when the abnormal noise occurred is within a predetermined torque range corresponding to the combination of the clutch and the manual transmission.