JP3874705B2 - Vehicle running sound tester - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vehicle running sound test machine for measuring noise generated between an asphalt mixture used in asphalt pavement and a wheel having a tire.
[0002]
[Prior art]
The contribution of tire / road surface noise to automobile noise is, for example, about 80% for passenger cars and about 60% for large cars in the case of steady running noise at a constant speed. Therefore, it is effective to reduce the tire / road surface noise to reduce road traffic noise. Therefore, it is necessary to measure tire / road surface noise and grasp the tire / road surface noise.
[0003]
However, conventionally, in order to measure the asphalt pavement surface and tire / road surface noise generated on the road, for example, on an expressway, the tire / road surface noise was actually measured by going to the expressway and using a noise meter.
[0004]
[Problems to be solved by the invention]
However, it is difficult to measure under the same conditions because the road surface condition and the surrounding conditions such as the presence or absence of the wall and the position are not constant between the inner lane and the outer lane of the expressway. Could not be compared.
[0005]
In addition, it was not only necessary to go to the expressway, but in order to carry out the measurement on the expressway, it was inevitable that it would be necessary to obtain permission from the public corporation.
[0006]
In addition, because the measurement is outdoors, the influence of weather conditions is inevitable, and correction to the environmental temperature is especially emphasized, and a method of correcting with the road surface temperature or the atmospheric temperature has been proposed, but it is consistent with each test method. The current situation is that it has not been removed.
[0007]
Furthermore, since tire / road noise has a speed dependency, a slight variation in speed greatly affects the sound pressure level of the tire / road noise when evaluating the noise. It was necessary.
[0008]
The present invention has been made in consideration of such problems.Similar noise measurement can be performed indoors without going on the road, and the influence on measurement results due to measurement location, environmental conditions, and speed variations. The aim is to provide no vehicle running sound testing machine.
[0009]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the invention described in claim 1 is a vehicle running sound test machine for measuring a sound generated by a specimen and a test wheel that moves while rotating on the specimen, The mounting body that mounts and holds the specimen and the rotating body that rotatably holds the test wheel at one end are rotated so that the test wheel moves circularly around the rotation center of the rotating body, and intermittently. A wheel moving means for moving the test wheel while rotating on the specimen, a sound measuring means for measuring the generated sound, and covering at least the specimen, the test wheel and the sound measuring means. Possible sound insulation means.
[0010]
In order to solve the above-mentioned problem, the invention according to claim 2 further includes a correction means for performing correction to delete unnecessary sound after the sound is measured by the sound measuring means.
[0011]
In order to solve the above-mentioned problem, the invention according to claim 4 is a position where the placing object is placed so that the load changes between the test wheel and the specimen. It is characterized by including a mounting position adjusting means capable of changing.
[0012]
In order to solve the above problems, the invention according to claim 5 is characterized in that the sound insulating means is configured to be detachable.
[0013]
In order to solve the above problems, the invention according to claim 6 is characterized in that the sound measuring means can be attached to the sound insulating means.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an example of a preferred embodiment of the present invention will be specifically described with reference to the drawings.
[0015]
First, a schematic configuration of the entire vehicle running sound measuring apparatus 1 (vehicle running sound testing machine) of the present invention will be described with reference to FIGS. FIG. 1 is a side view showing the configuration of the vehicle running sound measuring device 1 of this example. FIG. 2 is a perspective view showing the same configuration of the vehicle running sound measuring device 1 of this example. FIG. 3 is a cross-sectional view of the mounting body 5 to be described later, and is an explanatory view showing an aspect of adjusting the height position of the specimen support 52 to be described later. FIG. 4 is a side view showing a configuration of a traveling loading unit 4 to be described later. FIG. 5 is an explanatory view showing the mode of operation of the test wheel.
[0016]
As shown in FIGS. 1 and 2, the vehicle running sound measuring device 1 of this example rotates the test wheel 41 while generating a load between the test wheel 41 and the test body 2 on the specimen 2 on the paved road surface. And measuring the sound generated by the test wheel 41 and the specimen 2, for example, a structure for mounting and supporting various mechanisms, which will be described later, assembled by channel steel, angle steel, steel plate, etc. A running load section 4 as a wheel moving means for rotating the test wheel 41 while rotating the test wheel 41 while generating a load between the test body 41 and the test wheel 2; A mounting body 5 for mounting and holding the vehicle, an operation control unit 6 for operating the vehicle running sound measuring device 1, controlling each component, displaying a measurement result, and the like, and a sound measurement for measuring the generated sound Sound pressure level measuring device 7 as a means and sound insulation from outside It is constituted by a cover 8 as a sound means.
[0017]
As shown in FIG. 1, the mounting body 5 is placed on a load meter 51 fixed on the structure 3, and the load meter 51 measures a load applied by a test wheel 41. Further, the mounting body 5 is disposed such that the horizontal direction is regulated by the mounting body guide 53.
[0018]
Further, as shown in FIG. 3, the mounting body 5 mainly includes a specimen holder 52 and a mounting body base 54. A wedge shaft 542 that is threaded within a predetermined range is pivotally supported on the mounting body base 54, and the pair of wedges 543 are screwed to the wedge shaft 542 so that the slope of the wedge 543 faces each other. When the wedge shaft 542 is rotated by a ratchet handle 541 provided at one end of the wedge shaft 542, the pair of wedges 543 moves in a direction toward or away from the pair. Further, the slope image of the slope body 521 attached to the specimen holder 52 slides with the slope of the wedge 543 as the wedge 543 moves, so that the specimen as shown in FIGS. The configuration is such that the specimen cradle 52 is moved up and down to change the bending of the test wheel 41 to change the load generated between the test wheel 41 and the specimen 2 (details will be described later). In addition, the predetermined range in which the wedge shaft 542 is threaded may be, for example, a range in which the specimen support 52 can be sufficiently moved up and down so that an evaluation assuming a light vehicle or a large vehicle described later can be performed. By moving the specimen cradle 52 up and down in this manner, the load generated between the test wheel 41 and the specimen 2 can be changed by changing the deflection of the test wheel 41, and the mounting referred to in the present invention. Position adjustment means can be configured.
[0019]
Specimen 2 is an asphalt mixture placed in a box-shaped mold made of metal, has a size of 30 cm square or 50 cm square, and a thickness of approximately 5 cm, and is provided on specimen holder 52 by specimen bracket 21. It is placed so that it does not move back and forth and left and right.
[0020]
2 includes a drive motor 45, a drive shaft 42 for transmitting power, a test wheel 41 at one end, and a counter balancer 44 at the other end, and is intermittently driven by the rotation of the drive shaft 42. In particular, the test wheel 41 is composed of an arm 43 for moving the test wheel 41 while rotating the specimen 2. The test wheel 41 is a hub-like wheel provided with a rubber tire. Further, the arm 43 may have a disk shape as long as it is a rotating body that rotates by the drive shaft 42.
[0021]
Further, as shown in FIG. 4, the rotation of the drive motor 45 is decelerated by a speed reducer 451 and is connected to the drive shaft 42 by a joint 421. The drive shaft 42 is rotatably held by two bearings d422. The test wheel 41 is fixed to a flange portion provided on the outer ring of the bearing t461 with a shaft A46 attached to the arm 43 via a bearing t461, and the test wheel 41 is rotatable. The counter balancer 44 is a weight attached so that the distance from the rotation center of the arm 43 can be adjusted by an adjustment screw 441. The position of the counter balancer 44 from the rotation center of the arm 43 is adjusted according to the type of the test wheel 41 to be attached. Thus, the arm 43 can be smoothly rotated. The distance from the rotation center of the arm 43 to the farthest part of the test wheel 41 is longer than the distance from the upper surface of the specimen 2 to the rotation center of the arm 43.
[0022]
Accordingly, in this configuration, when the drive shaft 42 rotates in the T direction as shown in FIG. 5, the arm 43 rotates about the drive shaft 42 as a rotation center, and the test wheel 41 provided at one end is also the drive shaft. Perform a circular motion around 42. During the rotational movement, the test wheel 41 first contacts the specimen 2 placed on the specimen holder 52 and the arm 43 tries to rotate. At this time, the test wheel 41 is bent and the test wheel 41 is bent. A load is generated between the wheel 41 and the specimen 2, and a frictional force is generated between the test wheel 41 and the specimen 2 due to the load, and the test wheel 41 rolls on the specimen 2 due to the frictional force. The test wheel 41 moves away from the specimen 2 by the rotation of the arm 43 while rotating in the t direction. In this manner, the test wheel 41 can be moved while rotating on the test specimen 2 while generating a load between the test wheel 2 and the operation of the running wheel can be simulated. Therefore, the sound generated at this time can be treated as traveling sound by correcting the correlation with the traveling sound as will be described later. This sound is measured by a sound pressure level measuring device 7 described later. On the other hand, the generated load is measured by the load meter 51, and the load can be varied by changing the amount of bending of the test wheel 41 by raising and lowering the height of the specimen cradle 52 by the wedge 543 and the sloped body 521 described above. Can be changed.
[0023]
The sound pressure level measuring device 7 is held by a stand 71. The stand 71 can be easily fixed by moving its position with a detachable magnet, the height can be adjusted, and the sound pressure level measuring device 7 can be set at a position suitable for the evaluation method and contents. Further, the sound pressure level measuring device 7 is connected to an output device such as a printer (not shown) so that the sound pressure level measurement result can be output. It is also possible to incorporate a printer in the sound pressure level measuring device 7.
[0024]
Furthermore, the cover 8 is configured to include a sound insulating material, and can be fixed to the structure 3 with a mounting screw (not shown), for example, and removed by removing the mounting screw. Therefore, by installing the cover 8, it is possible to measure the sound generated by the test wheel 41 and the specimen 2 while being sound-insulated from the outside. Further, by removing the cover 8, the test wheel 41 and the specimen 2 can be easily replaced and the sound pressure level measuring device 7 can be easily installed. In order to reduce the influence of reflected sound or the like, it is more preferable that a sound absorbing material is provided on the inner surface of the cover 8. Further, if the sound pressure level measuring device 7 can be attached to the cover 8, the trouble of installing the sound pressure level measuring device 7 can be saved. The cover 8 may be installed and removed by positioning and placing on the structure 3 by positioning means such as fitting, without using the means for fixing such as the mounting screws described above.
[0025]
As shown in FIG. 1, the operation control unit 6 includes a control panel 61 and a relay panel (not shown) attached to the frame-like structure 3 side. , Based on the operation setting unit 62 for setting the number of rotations of the drive motor 45 (or the moving speed of the test wheel 41) or setting the number of movements, the above numerical values and the load meter 51 A display unit 63 made up of instruments for displaying pressure and the like is provided.
[0026]
Although not shown in the figure, the operation control unit 6 includes a main control unit that controls each component according to a predetermined control program and performs various arithmetic processes. The drive motor 45 is controlled based on the number of rotations and the number of movements set in the setting unit 62.
[0027]
In the above description, the sound pressure level measuring device 7 is described as being output from the printer. However, the sound pressure level measuring device 7 is provided with a sound pressure level measurement result processing unit (not shown) in the operation control unit 6. The output signal may be taken into the operation control unit 6 and output. Alternatively, a microphone may be installed in place of the sound pressure level measuring device 7, the output of the microphone may be taken into the operation control unit 6, and the processing function of the sound pressure level measuring device 7 may be provided in the operation control unit 6 for processing. Is possible.
[0028]
The outline of the procedure for performing the test will be described below. First, the cover 8 is removed, and the specimen 2 and the test wheel 41 are installed and attached. As described above, since the specimen 2 can be easily replaced by simply placing it in the specimen bracket 21 on the specimen holder 52, the specimen 2 having various compositions can be replaced by replacing the specimen 2 having various compositions. The sample 2 can be easily evaluated. Therefore, when it is desired to evaluate various pavement surfaces, the desired evaluation can be performed only by preparing the specimens 2 corresponding to the various pavement surfaces without going to a plurality of places.
[0029]
Further, since the test wheel 41 can be easily replaced by simply attaching it to the flange portion of the bearing t461 as described above, the test wheel 41 made of a different material (rubber) or the test wheel 41 having a different surface condition (for example, a hole in the surface). It is possible to evaluate various test wheels 41 by exchanging the ones that have been opened and those that cannot be opened.
[0030]
Further, in order to set the load generated between the specimen 2 and the test wheel 41 at the time of measurement to a desired load, the specimen holder 52 is operated at a predetermined height by operating the ratchet handle 541 as described above. adjust. At this time, the output of the load meter 51 may be performed while checking the display unit 63. By this height adjustment, for example, an evaluation assuming a light vehicle can be performed by reducing the load, and an evaluation assuming a large vehicle can be performed by increasing the load.
[0031]
In addition, it is possible to evaluate a variety of purposes and conditions by combining the specimen 2, the test wheel 41, and various loads generated between the specimen 2 and the test wheel 41. I can say that.
[0032]
Then, after the cover 8 is installed and the number of rotations and the number of movements of the drive motor 45 are set, the drive motor 45 is moved and the test wheel 41 is moved while rotating on the specimen 2 while applying a load. The sound generated at that time is measured. At this time, the load or the like between the test wheel 41 and the specimen 2 can be confirmed by the display unit 63. Further, since the moving speed of the test wheel 41 is determined only by the number of rotations of the drive motor 45, the moving speed of the test wheel 41 is constant, and is an inevitable driving speed when actually measuring the sound by running the wheel. There is no variation.
[0033]
Further, since the cover 8 can be installed and removed, if the room is sound-insulated from the outside, the evaluation may be performed by removing the cover 8.
[0034]
As apparent from the above and FIG. 1 to FIG. 5, according to the vehicle running sound measuring device 1, the entire device is downsized and can be installed indoors. If the wheels 41 are prepared, the noise can be easily measured without going out on the road, and further, the measurement equivalent to the tire / road noise when the vehicle is actually driven can be performed by performing correction as described later. Become. Furthermore, noise can be measured in a room where the environment is almost constant, and the moving speed of the test wheel 41 can be kept constant, so that measurement results that are not affected by measurement location, environmental conditions, speed variations, and the like are obtained. It is possible.
[0035]
Further, the moving speed of the test wheel 41 at the time of measurement by the vehicle running sound measuring device 1, the load between the test wheel 41 and the specimen 2, and the moving speed of the test wheel 41 when actually running using an automobile. The generated sound differs depending on the difference in load between the test wheel 41 and the specimen 2 or the like, but correlation data between the generated sound and the sound when actually running is obtained in advance. Thus, it is easy to convert the measurement result obtained by the vehicle running sound measuring device 1 into a measurement result obtained by actually running the vehicle. For example, the operation control unit 6 captures the output signal of the sound pressure level measuring device 7 or the microphone, the correlation data is stored in the operation control unit 6 in advance, and the correlation signal is correlated with the captured output signal to correlate the output signal. It is possible to correct based on the data.
[0036]
Here, in the present embodiment, the test wheel 41 is moved circularly by the arm 43, and it is considered that an impact sound is generated when the test wheel 41 collides with the specimen 2. In this case, it is preferable to correct the impact sound. That is, the operation control unit 6 is provided with a sound pressure level measurement result correction unit as a correction means, and the operation control unit 6 takes in the output signal of the sound pressure level measuring device 7 or the microphone, and the sound pressure level measurement result correction unit corrects it. Can be done. Specifically, for example, information on impact sound, for example, information such as frequency band and amplitude magnitude is stored, and the captured output signal is compared with the information to determine whether the captured output signal is the impact sound. In the case of an impact sound, correction is performed so that the captured output signal is deleted. Further, since the impact sound is generated when a load is generated between the specimen 2 and the test wheel 41, the load is obtained while the output signal of the sound pressure level measuring device 7 or the microphone is taken into the operation control unit 6. The output of the total 51 can also be captured, and the output signal captured near the time of load generation can be corrected to be estimated and deleted as an impact sound. In addition, this correction is not limited to the collision sound, and other sounds that do not occur in measurement by actual traveling may be corrected. By correcting the measurement result in this way and taking countermeasures such as an impact sound, a more accurate measurement result can be obtained.
[0037]
【The invention's effect】
As described above, according to the invention described in claim 1, since the entire apparatus is downsized and can be installed indoors, if the specimen and the test wheel are prepared, The tire / road noise can be easily measured without going out. Furthermore, the noise of the tire / road surface can be measured in a room where the environment is almost constant, and the moving speed of the test wheel can be kept constant, so there is no influence of measurement location, environmental conditions, speed variations, etc. Measurement results can be obtained.
[0038]
According to the second aspect of the present invention, a more accurate result can be obtained by performing correction in consideration of unnecessary sounds.
[0039]
According to the invention described in claim 4, by making the load generated between the test wheel and the specimen variable, it is possible to perform noise measurement assuming a light vehicle or a large vehicle, for example.
[0040]
According to the fifth aspect of the present invention, it is easy to replace the test wheel and the specimen and to install sound measuring means such as a sound pressure level measuring device.
[0041]
According to the sixth aspect of the invention, it is possible to save the trouble of installing the sound measuring means.
[Brief description of the drawings]
FIG. 1 is a side view showing a configuration of a vehicle running sound measuring device according to an embodiment of the present invention.
FIG. 2 is a perspective view showing the vehicle running sound measuring device.
FIG. 3 is an explanatory view showing an aspect of adjusting the height position of the mounting body.
FIG. 4 is a side view showing a configuration of a traveling loading unit.
FIG. 5 is an explanatory diagram showing a mode of operation of a test wheel.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Vehicle running sound measuring apparatus 2 Specimen 3 Structure 4 Running load part 42 Drive shaft 421 Joint 422 Bearing d
43 Arm 44 Counter balancer 441 Adjustment screw 45 Drive motor 451 Reducer 46 Axis A
461 Bearing t
5 Mounting body 52 Specimen base 521 Slope body 53 Mounting body guide 54 Mounting body base 541 Ratchet handle 542 Wedge shaft 543 Wedge 6 Operation control unit 61 Control panel 62 Operation setting unit 63 Display unit 7 Sound pressure level measuring device 71 Stand 8 Cover 21 Specimen Bracket 41 Test Wheel 51 Load Cell

Claims (8)

A vehicle running sound test machine for measuring a sound generated by a specimen and a test wheel that moves while rotating on the specimen,
A mounting body for mounting and holding the specimen;
While rotating the rotating body holding the test wheel at one end so as to be rotatable, the test wheel is circularly moved around the rotation center of the rotating body, and the test wheel is intermittently rotated on the specimen. Wheel moving means for moving;
Sound measuring means for measuring the generated sound;
A vehicle running sound testing machine comprising: a sound insulating means capable of covering at least the specimen, the test wheel, and the sound measuring means. 2. The vehicle running sound testing machine according to claim 1, further comprising correction means for performing correction for deleting unnecessary sound after the sound is measured by the sound measuring means. 3. The vehicle running sound test machine according to claim 2, wherein the unnecessary sound is an impact sound generated when the test wheel collides with the specimen by the wheel moving means. The mounting body includes a mounting position adjusting unit capable of changing a position on which the test body is mounted so as to change a load generated between the test wheel and the test body. The vehicle running sound testing machine according to any one of claims 1 to 3. 5. The vehicle running sound testing machine according to claim 1, wherein the sound insulating means is configured to be detachable. 6. The vehicle running sound testing machine according to claim 1, wherein the sound measuring means can be attached to the sound insulating means. The vehicle running sound testing machine according to any one of claims 1 to 6, wherein the rotating body is an arm, and the test wheel is rotatably held at one end of the arm. The vehicle running sound testing machine according to claim 7, wherein the rotation center is a substantial center of the arm, and a weight attached to the other end so that a distance from the rotation center can be changed.

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