JP2797718B2 - Automatic low-pitched sound judgment device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to low-grade sounds such as chattering noises and rattling sounds which can be used for detecting abnormalities of a vehicle on a vehicle assembly line inspection line or the like. The present invention relates to an apparatus for automatically determining the occurrence of the occurrence.

[0002]

2. Description of the Related Art FIG. 13 shows a conventional method for judging the occurrence of a low-pitched sound from the noise in a vehicle vibrating due to pseudo running.

In other words, in this method, two freely rotatable rough rollers 1 having irregularities on the surface and drivingly connected to each other are installed on an inspection line of a vehicle factory, and the vehicle 2 to be inspected is placed on the rough rollers 1. Inspection vehicle 2
An inspector gets inside and starts the engine.
While creating the simulated running state above, the inspector finds out the abnormality of the vehicle by listening to the low-pitched sound from the noise generated inside the vehicle to be inspected 2.

[0004]

However, in the above-described conventional low-pitched sound determination method, since the inspector directly rides on the vehicle and is vibrated, the physical burden on the inspector is large, and the inspector is far from the driver's seat. There is a problem that it is difficult to hear the sound generated at the place, a problem that it is not possible to concentrate on listening to the low-pitched sound due to the driving operation, and a problem that the low noise is caused by the engine sound and other normal noise generated from the vehicle itself. There is a problem that the sound may be missed, and in addition, there is a problem that the test result varies when the inspector is different.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to advantageously solve the above-mentioned problems of the conventional low-pitched tone determination method. In-vehicle noise collecting means for collecting noise in the vehicle at a plurality of locations in the vehicle and taking it out of the vehicle by radio communication using radio waves, vibration means for inputting vibration to the vehicle to be inspected, and the in-vehicle noise collecting means The frequency band to be collected is divided into a plurality of frequency blocks, and determination data for each of the frequency blocks is given in advance for each vibration condition. Low frequency sound data indicating which frequency block belongs to which of the frequency blocks is given in advance, and the vibrating means is operated under the condition that vibration is input to the vehicle to be inspected. The noise in the vehicle collected by the vehicle interior noise collecting means is compared with the determination data under the same vibration condition for each of the frequency blocks, and a noise having a level exceeding an upper limit value of the determination data is generated for the plurality of frequency blocks. If it is present in at least one of the frequency blocks,
It is determined that a low-pitched sound has occurred, and at least one frequency block in which noise having a level exceeding the upper limit value of the determination data is any of the plurality of frequency blocks, and based on the low-pitched sound data. hand,
And low-pitched tone determining means for determining the type of low-pitched tone generated.

[0006]

In such an apparatus, the vibration means inputs vibration to the vehicle to be inspected, and the vehicle interior noise collecting means collects the noise in the vehicle of the vehicle to be inspected at a plurality of locations under the vibration input state. The low-frequency sound determination means divides the frequency band in which the vehicle interior noise collection means collects the sound into a plurality of frequency blocks, and determines each of the frequency blocks for each vibration condition. Data is given in advance, and low-pitched sound data indicating in advance which of the plurality of frequency blocks the characteristic peak level of the low-pitched tone belongs to for each type of low-pitched tone is added. When the vibration means inputs vibration to the vehicle to be inspected, the vehicle interior noise collected by the vehicle interior noise collection means is compared with the determination data under the same vibration conditions for each of the frequency blocks. When noise at a level exceeding the upper limit of the determination data is present in at least one of the plurality of frequency blocks, it is determined that a low-pitched sound has occurred, and the upper limit of the determination data is determined. The type of low-pitched tone generated is determined based on which of the plurality of frequency blocks the at least one frequency block in which the level of noise was present and the low-pitched tone data.

Therefore, according to the apparatus of the present invention, since the inspector does not get on the vehicle directly and is excited, the physical burden on the inspector can be reduced and the noise collection means inside the vehicle can be collected. Collects noise in the vehicle at multiple locations inside the vehicle and picks it out of the vehicle by radio communication using radio waves. Sound can be reliably collected without hindrance, and the vibration means inputs vibration to the vehicle to be inspected to create a simulated running state, so that it is not possible to concentrate on listening to low-pitched sounds by driving operation, and the vehicle itself The low-pitched sound is prevented from being missed by the low-pitched sound because it is disturbed by engine noise and other normal noise generated from the vehicle. For each of the frequency blocks, the determination data under the same vibration condition given in advance and the noise are compared to determine the occurrence of the low-pitched sound, and the frequency block in which the noise of the level exceeding the upper limit value of the determination data exists. And the type of low-pitched tone generated based on the low-pitched tone data given in advance, it is possible to reliably obtain a test result of a certain level even if inspectors are different.

[0008]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of an automatic low-pitched sound judging apparatus according to the present invention. In FIG. And 13 denote arithmetic processing units as low-pitched tone determination means, respectively.

The in-vehicle noise collecting apparatus 11 includes a microphone 21 and a transmitter 22 that converts the in-vehicle noise collected by the microphone 21 into radio waves and transmits the radio wave. The set consists of two sets: A set at the front of the car and B set at the rear of the car.
There is a set. Further, the in-vehicle noise collection device 11 receives the radio waves from the transmitters 22 of the set A and the set B, converts the radio waves into analog voltage signals, and the microphones 21 of the set A and the set B collect sound. A wireless receiver 23 that outputs noise inside the vehicle, and the wireless receiver 23
And an headphones 24 connected to the amplifier 24 so that the inspector can directly listen to the output signal.

The vibrating device 12 includes two vibrators 31 that vibrate the vehicle 2 to be inspected by a crank driven by a motor and that can arbitrarily change the vibration frequency and thus the vibration force.
And the operation of the motor of the vibrator 31
For example, a shaker control panel 32 having a programmable controller is provided which sequentially performs several exciting modes in which the exciting time and the exciting force are combined.

As shown in FIG. 2, the arithmetic processing unit 13 specifically includes a central processing unit (CPU) 41.
And a storage circuit (RAM, ROM) (not shown) for performing fast Fourier analysis (FFT), a storage unit 43 for storing data of measurement conditions, judgment conditions and failure phenomena, and execution of a measurement program. A measurement control unit 44 for controlling and determining the occurrence of a bass tone, a display unit 45 for displaying the judgment result, a keyboard unit 46 for inputting measurement conditions from outside, and a printer for printing and outputting the judgment result 47, an analog / digital (A / D) conversion unit 48, a pulse unit 49, a floppy control unit 50, and a hard disk interface 51.

The in-vehicle sound output from the amplifier 24 is input to the A / D conversion unit 48 as an analog signal, and the pulse unit 49 is used to measure the in-vehicle sound corresponding to the vibration input. A vibration input condition signal from the vibration control panel 32 is input, and the floppy control unit 50 sends a measurement condition program, a judgment condition program, a frequency analysis program, and a judgment value database to the floppy disk 52 set in the floppy disk drive. Reads data from the hard disk and stores recorded data and analysis data.
Performs reading and writing of data with respect to the low-pitched sound database in the hard disk 53.

The measurement condition program defines the content of frequency analysis for each vehicle type as shown in FIG. 3, for example, and the determination condition program defines the number of excitation modes as shown in FIG. , The total vibration time, the output condition of the determination result, and the like are defined for each vehicle type. The determination value database is, for example, shown in a table in FIG.
As shown by the graph in (b), a plurality of frequency points are determined from the frequency analysis result of the in-vehicle noise when a vibrating force is applied in a predetermined vibration mode to the vehicle for which it has been confirmed that no low-grade sound is generated. The sound pressure levels at those points are read out, and the values of the line graph obtained by linearly interpolating the sound pressure levels at those frequency points are defined as judgment values for each vehicle type and each vibration mode.

The low-pitched sound database is used to search for an estimated phenomenon and cause when a low-pitched sound is generated, for example, as shown in FIG. The frequency range of the measurement range is divided into a plurality of frequency blocks, and the frequency range of the measurement range is divided into a plurality of frequency blocks, and the measurement is performed in advance in accordance with the above setting conditions for each type of low-pitched tone. For example, the rattling sound of a spare tire board has a sound pressure distribution as shown in FIG. 7A, and the chattering sound of a trunk lid torsion bar has a sound pressure distribution as shown in FIG. 7B. A particularly large characteristic peak level is extracted from the sound pressure distribution, and one or more of the plurality of frequency blocks to which the one or more characteristic peak levels belong. A plurality of frequency blocks, is reported to investigate the extent of its characteristic peak level. If new low-pitched tone data is available, it can be added to this database.

In such a low-pitched-tone automatic discriminating apparatus, a low-pitched tone is automatically discriminated according to a procedure as shown in FIG. That is, here, the exciter control panel 32 of the
As a vibration mode to be sequentially performed by the vibrator 31, for example, as shown in the upper part of FIG. 9, a total of 6 vibration modes are input every 10 seconds in each mode, and first, in step 101,
The inspected vehicle 2 is put on the vibration exciter 31 installed in the soundproof booth in the vehicle factory, and in the following step 102, the inspector places the microphone 21 and the transmitter 22 in front of the inspected vehicle 2 inside the vehicle. Is set, and a set B of the microphone 21 and the transmitter 22 is installed at the rear of the vehicle. As a result, each transmitter 22 converts the in-vehicle sound collected by each microphone 21 into a radio wave of a different frequency, transmits the radio wave to the outside of the vehicle, and causes a wireless receiver 23 installed outside the vehicle to receive the radio wave. Then, the wireless receiver 23 sends the received radio wave to the amplifier 24 as an analog voltage signal,
Amplifies the signal, sends it to the low-pitched sound judging device 13 and outputs it to the headphones 25.

Next, here, in step 103, the inspector gets off the inspected vehicle 2, and the inspector
To set the automatic / manual selection switch of the vibration exciter control panel 32 to the automatic vibration mode, and input the vehicle type number from the keyboard 46 to the low-pitched sound judging device 13 by key operation at step 105. By setting the automatic vibration mode in the above step 104, the vibrator 31 prepares for the excitation start in step 121. In addition, in response to the key operation input of the vehicle type number in step 105, the arithmetic processing unit 13 determines in step 131, in addition to the frequency analysis program, the measurement condition program and the determination condition program and the determination value corresponding to the vehicle type of the vehicle type number, The data is read from the floppy disks and set. However, if there is no key operation input in the continuous inspection of the same model, the previously set programs and conditions are used as they are. When the setting is completed, the arithmetic processing unit 13 outputs a measurement preparation completion signal to the vibrator control panel 32 in step 132, whereby the vibration preparation is completed in step 122. The exciter control panel 32 is configured so that the exciter is not started even if the exciter start switch is turned on until the measurement preparation completion signal is input.

Thereafter, when the inspector turns on the shaker start switch of the shaker control panel 32 in step 106,
Excitation start-up of the exciter 31 starts at 123 and the following steps
At 124, the vibration exciter control panel 32 outputs a measurement start signal to the arithmetic processing unit 13 after a predetermined time at which the excitation force stabilizes, and accordingly, at step 133, the arithmetic processing unit 13 starts the in-vehicle noise measurement. I do. In this measurement, as shown by the method A in FIG. 10, in the vibration state in the vibration mode, first, the noise data acquisition and the frequency analysis of the processing a are performed as shown in the middle part of FIG. The process is performed, and then the cause of the process c is searched, and the result of the process d is displayed as shown in the lower part of FIG.

Here, as shown in FIG. 12, the judgment processing of the processing b is performed by taking in-vehicle noise data in the processing a, analyzing the frequency of the noise data by FFT, and the judgment value in the form of a line graph. When the noise data n includes a frequency portion having a higher sound pressure level than the determination value j, it is determined that a low-pitched sound is generated. Further, the cause search of the processing c is performed by determining the determination value j of the noise data n in the database shown in FIG.
A cause search is executed on the basis of a frequency part having a higher sound pressure level, and a cause corresponding to the frequency part is read out therefrom.

When one vibration mode ends, the vibrator control panel 32 outputs a vibration mode switching signal to the processing unit 13 in step 125, and the processing unit 13
In step 134, noise data acquisition, frequency analysis, determination processing, cause search, and display of the result are performed in the excitation state in the next excitation mode. On the other hand, during the excitation and processing in each of these excitation modes, the inspector directly listens to the vehicle interior noise using the headphones 25 in step 107.

When the excitation in all the excitation modes by the excitation device 12 is completed in step 126, and all the measurements are completed in step 135, the arithmetic processing unit 13
Goes to step 136 and displays the overall judgment result as shown in FIG. 11, for example.The inspector confirms the judgment result by the display in step 108, and then gets on the measured vehicle in step 109, and At 110, the vehicle is unloaded. The vibration device 12 returns to step 121 to wait for the next vehicle.

The result of the determination is rejected (NG) because a low-pitched tone is generated, and the inspector determines in step 111 that the result must be printed out (printed out).
When the key is operated at 112, the arithmetic processing unit 13
In step 7, the contents of the key operation are determined, and in step 138, the first NG screen is printed out, or in step 139, an arbitrary screen is printed out. In addition, the inspector
In step 113, it is determined that it is necessary to directly listen to the vehicle interior noise again in the NG mode in which the low-pitched sound is generated.
Set the automatic / manual selection switch of the vibrator control panel 32 to the manual (manual) vibration mode with the
Is fixed to the vibration in the NG mode, the vibration device 12
Step 127 sets the manual mode.
At 128, vibration is performed in the NG mode. This allows the inspector to directly listen to the noise in the vehicle in the NG mode with the headphones 25 in step 115 to confirm the noise. When the vibration is completed in step 129, the vibration device 12 returns to step 121 and waits for the next vehicle as in step 126.

Therefore, according to the apparatus of this embodiment, since the inspector does not directly ride on the vehicle and is vibrated, the physical burden on the inspector can be reduced, and the noise collection inside the vehicle can be achieved. Since the device 11 collects the noise in the vehicle at two places and takes it out of the vehicle, the noise generated in the entire vehicle can be collected, and the vibration device 12 inputs the vibration to the vehicle to be inspected and creates a simulated traveling state. Therefore, it is not possible to concentrate on listening to low-pitched sounds due to driving operation, and it is not possible to miss low-pitched sounds due to engine noise or other normal noise generated from the vehicle itself. apparatus
13 determines the occurrence of the low-pitched sound by comparing with predetermined judgment data under the same vibration condition, so that a certain level of test result can be obtained even if the inspector is different. Moreover, according to the apparatus of this embodiment, a cause search is performed using the low-pitched sound database, and the cause of the low-pitched sound is displayed, so that the repair time of the vehicle can be reduced.

Although the present invention has been described based on the illustrated example, the present invention is not limited to the above example. For example, a plurality of CPUs 41 may be provided in the arithmetic processing unit 13 so that the frequency analysis unit 42 and the measurement control unit 44 Can be operated independently, and as shown in the method B in FIG. 10, the frequency analysis unit 42 performs the acquisition of the noise data and the frequency analysis of the process a in all times except the time required for data transfer in one vibration mode. Then, the data may be transferred to the measurement control unit 44 in the process e, and the determination process of the process b, the cause search of the process c, and the result display of the process d may be performed during the next excitation mode. This makes it possible to increase the ratio of the noise data capture processing time in one vibration mode as compared with the previous embodiment.

[0024]

As described above, according to the apparatus of the present invention, since the inspector does not directly ride on the vehicle and is shaken, the physical burden on the inspector can be reduced, and the noise collection inside the vehicle can be achieved. Since the means collects noise inside the vehicle at multiple places inside the vehicle and takes it out of the vehicle by radio communication using radio waves, the noise generated throughout the vehicle can be violently vibrated from inside the vehicle to the outside of the vehicle due to resonance or disconnection of the microphone code Sound can be reliably collected without being hindered, and the vibration means inputs vibration to the vehicle to be inspected to create a simulated running state. The low-pitched sound is not missed because it is interrupted by the engine noise and other normal noise generated from itself.In addition, the low-pitched sound judging means increases the frequency For each divided frequency block, the judgment data under the same vibration condition given in advance is compared with the noise to judge the occurrence of the low-pitched sound, and the frequency at which the noise with the level exceeding the upper limit of the judgment data is present Since the type of the generated low-pitched tone is determined based on the block and the low-pitched tone data given in advance, a certain level of test result can be reliably obtained even if the inspector is different.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of an automatic low-pitched tone determination device of the present invention.

FIG. 2 is a block diagram showing in detail the configuration of an automatic low-pitched tone determination device of the embodiment.

FIG. 3 is a diagram showing an example of a measurement condition program used in the apparatus of the embodiment.

FIG. 4 is a diagram showing an example of a determination condition program used in the apparatus of the embodiment.

FIG. 5A is a diagram showing an example of a judgment value database used in the apparatus of the embodiment in the form of a table, and FIG. 5B is a diagram showing an example of the judgment value database in the form of a graph.

FIG. 6 is a diagram showing an example of a low-pitched sound database used in the apparatus of the embodiment.

FIGS. 7A and 7B are characteristic diagrams respectively showing frequency distributions of two types of data in the low-pitched sound database.

FIG. 8 is a flowchart showing an operation procedure of the apparatus of the embodiment.

FIG. 9 is a time chart showing an operation procedure of the apparatus of the embodiment.

FIG. 10 is a time chart showing a method of measuring noise in the apparatus of the embodiment.

FIG. 11 is an explanatory diagram showing a display example of a comprehensive judgment result in the apparatus of the embodiment.

FIG. 12 is a characteristic diagram showing a method of determining a low-pitched tone in the apparatus of the embodiment.

FIG. 13 is an explanatory diagram showing a conventional low-pitched tone determination method.

[Explanation of symbols]

 2 Vehicle to be inspected 11 In-car noise collection device 12 Exciter 13 Processing unit

Claims (1)

(57) [Claims] [Claim 1] A vehicle interior noise sound collecting means for the interior noise of the inspected vehicle collected by the multi <br/> several locations of the vehicle taken out of the vehicle by wireless communication using radio waves (11), the inspection vehicle Vibrating means (12) for inputting vibration to the vehicle , and a frequency band in which the vehicle interior noise collecting means collects the sound.
Each frequency block is divided into
If the judgment data about the lock is given in advance
In both cases, the characteristic peak level of the
Bell is any frequency of the plurality of frequency blocks
The low-pitched tone data indicating whether the block belongs
Erare, wherein at the same vibrating condition car noise the vehicle interior noise sound collecting means is collected in a state where vibration means is entering vibration in the inspection vehicle for each of the respective frequency blocks <br /> compared to decision data, low noise levels exceeding the upper limit of the determination data of the plurality of frequency blocks
When present at one frequency block even without, with judges that lower sound occurs, on the decision data
At least one of the noise levels
The frequency block is any of the plurality of frequency blocks
And based on the bass data,
An automatic low-pitched-sound determining device, comprising: a low-pitched-tone determining means (13) for determining the type of the low-pitched tone.