JP4151492B2 - Soundproof device for chassis dynamometer - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a soundproofing device installed in a chassis dynamometer that is a vehicle testing device.
[0002]
[Prior art]
It is difficult to perform a vehicle running experiment in a predetermined running mode, for example, a test related to exhaust gas and fuel consumption by actually running on the road. The chassis dynamometer is a device that allows a test to be performed in a stationary manner by simulating traveling on the road, and the driving wheel of the vehicle to be tested is positioned on a roller instead of the actual road surface. In this way, the vehicle is mounted, and the output of the driving wheel is absorbed by the rotation of the roller to simulate the running state.
[0003]
As a technology related to such a chassis dynamometer, the safety shelf installed in the test apparatus can be moved, and the safety fence can be rotated so that the safety fence does not get in the way when the vehicle door set in the vehicle is opened. What was made is known (for example, refer to Patent Document 1).
[0004]
In addition, in a drum device that includes a rotation shaft and a cylindrical drum fixed to the rotation shaft, and mounts and supports the vehicle via the tire on the cylindrical drum, and transmits and rotates the rotation of the tire. A drum filled with a plastic foam material is known (for example, see Patent Document 2).
[0005]
[Patent Document 1]
Japanese Utility Model Publication No. 5-11044 [Patent Document 2]
Japanese Utility Model Publication No. 1-99041 [Problems to be solved by the invention]
When measuring the exhaust gas of a vehicle and performing an emission confirmation test, etc., the vehicle is placed on the above-mentioned chassis dynamometer and measured, but during the test, the vehicle's drive wheels and rollers rotate. There is a problem that a loud noise is generated. This noise level is, for example, 90 dB or more. For this reason, workers need to wear protective equipment such as earplugs and earmuffs, but when using protective equipment such as earplugs and earmuffs, workers must be aware of the dirt attached to them and the feeling of pressure on the ears. Feels hygienic and mental discomfort and pain.
[0006]
The present invention has been made in view of such problems, and an object thereof is to reduce noise generated by rotation of driving wheels and rollers of a vehicle during a test using a chassis dynamometer as a vehicle test apparatus. An object of the present invention is to provide a soundproof device for a chassis dynamometer that can easily perform work associated with a vehicle test.
[0007]
[Means for Solving the Problems]
In one aspect of the present invention, a soundproof device for a chassis dynamometer has an opening portion that is disposed to face a side surface of a vehicle, and a main body that houses a sound-absorbing material therein and a spring that is located above the main body. And a movable frame portion movable between a raised position and a lowered position that is a front position of the opening. The movable frame portion is provided with a cushioning material on a side surface facing the vehicle, and the lowered It contacts the side surface of the vehicle so as to cover the periphery of the drive wheel of the vehicle through the cushion material at the position.
[0008]
The soundproofing device described above is installed around the left and right drive wheels during a vehicle running characteristic test using a chassis dynamometer. The main body of the soundproofing device includes an opening facing the side surface of the vehicle and a sound absorbing material inside, and absorbs noise generated by the driving wheels and the rollers of the chassis dynamometer during the running characteristic test. Moreover, it also has a role as a safety cover by covering the outside of the drive wheel. The movable frame portion is in the lowered position during the running characteristic test and is installed around the drive wheels of the vehicle. Due to the elastic deformation of the cushion material, it is possible to prevent a gap from being generated between the movable frame portion and the vehicle side portion, thereby enhancing the soundproofing effect. In this way, the noise level during the running characteristic test can be reduced to a level where the operator does not need to wear earplugs or earmuffs.
[0009]
On the other hand, when the vehicle is moved relative to the chassis dynamometer before and after the running characteristic test, the movable frame portion is moved to the flip-up position above the main body of the soundproofing device. Therefore, the movable frame portion does not get in the way when the vehicle moves, and smooth operation is possible.
[0010]
In one aspect of the above-described chassis dynamometer soundproofing device, the movable frame portion is positioned rearward of the opening at the flip-up position. Thereby, in the flip-up position, a sufficient space can be secured between the main body of the soundproofing device and the vehicle, and the workability when moving the vehicle can be improved.
[0011]
In another aspect of the above-described chassis dynamometer soundproofing device, the sound absorbing material has irregularities formed on the surface on the opening side. Thereby, the surface area of the sound absorbing material can be increased, and the sound absorption efficiency can be increased. Therefore, when using a sound absorbing material of the same size, the sound absorbing effect can be enhanced. Conversely, even if the thickness of the sound absorbing material is reduced, the same sound absorbing effect can be ensured.
[0012]
In another aspect of the above sound proof device for chassis dynamometer, an air nozzle for forming an air flow is provided inside the main body. Since the soundproofing device has a structure that covers the periphery of the drive wheel, heat can be easily trapped inside, and the test results such as fuel consumption and emission can be affected by heat. Therefore, by providing an air nozzle and ventilating, it is possible to release the heat inside the main body and eliminate the influence on the measurement result.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Preferred embodiments of the present invention will be described below with reference to the drawings.
[0014]
FIG. 1 is a side view showing an overall configuration of a vehicle testing apparatus to which a chassis dynamometer soundproofing device (hereinafter simply referred to as “soundproofing device 100”) according to the present invention is applied, and FIG. 2 is a front view thereof. . 1 and 2, the chassis dynamometer 1 includes a roller 2 that is rotatably mounted at a position where the driving wheel 4 of the test vehicle 3 is disposed. The test vehicle 3 is arranged on the chassis dynamometer 1 such that the drive wheels 4 (front wheels in this example) are located on the rollers 2 of the chassis dynamometer 1. In FIG. 1, as an example of vehicle measurement using the chassis dynamometer 1, the exhaust gas discharged from the exhaust pipe of the test vehicle 3 is measured by the analyzer 5. That is, when the driving wheel 4 of the test vehicle 3 disposed on the chassis dynamometer 1 is driven, the driving wheel 4 rotates on the roller 2. In this state, exhaust gas discharged from the exhaust pipe of the test vehicle 3 is introduced into the analyzer 5 and analyzed.
[0015]
In such a vehicle test, due to the rotation of the drive wheel 4 and the roller 2 of the test vehicle 3, a large noise is generated from the vicinity of the drive wheel 4. In order to reduce this noise, in the present invention, as shown in FIGS. 1 and 2, a soundproof device 100 for covering the noise source and absorbing the noise is provided outside the two drive wheels 4 serving as the noise source. Install.
[0016]
Fig.3 (a) is a perspective view which shows schematic structure of the soundproofing apparatus 100 of this invention.
[0017]
The soundproofing device 100 has a structure like an earmuff, and is roughly composed of a main body 101 and a flip-up movable frame portion 102. FIG. 3A shows a state where the movable frame portion 102 is lowered, that is, a state where the movable frame portion 102 is disposed so as to contact the test vehicle 3 (hereinafter also referred to as “lowering state”), and FIG. A state in which the frame 102 is flipped up (hereinafter also referred to as a “bounce-up state”) is shown. The main body 101 is fixed. The main body 101 has an opening 107 on the side facing the vehicle, that is, the side where the movable frame 102 is provided, and the sound absorbing material 104 is accommodated in the opening 107.
[0018]
The movable frame portion 102 is formed by fixing a cushion material 102aa on a frame 102b made of metal or the like. The cushion material 102a is formed of, for example, a foam material, rubber, or other elastically deformable material, and is attached to the frame 102b with, for example, an adhesive. The movable frame portion 102 is provided so as to be movable in the direction of the arrow 120 with respect to the main body 101 by a rotating mechanism such as a plurality of arms (not shown). A handle 106 is provided on the top of the frame 102b. The operator can raise and lower the handle 106 to bring the movable frame portion 102 into a flip-up state and a lowering state. In this example, an example in which the movable frame unit 102 is raised and lowered manually by an operator is shown, but the movable frame 102 may be raised and lowered using a motor (not shown).
[0019]
Further, as shown in FIG. 3B, a sealing material 109 such as a cushion rubber is attached to a position on the outer peripheral surface of the main body 101 and the inner peripheral surface of the movable frame portion 102 to contact the main body 101. It is more preferable to prevent noise from leaking out from the gap between the movable frame 102.
[0020]
4 (a) and 4 (b) are horizontal sectional views taken along line II ′ of FIGS. 3 (a) and 3 (b), respectively, and FIG. 4 (a) is a lowering of the movable frame 102. The state is shown, and FIG. 4B shows the flip-up state. In FIGS. 4A and 4B, the side portion of the test vehicle 3 is indicated by a broken line.
[0021]
As shown in FIGS. 3 (b) and 4 (b), the movable frame portion 102 is retracted to the main body 101 side of the soundproof device 100 in the flip-up state, so that a predetermined width is provided between the side portion of the vehicle and the soundproof device 100. Space SP. Preferably, it is preferable that the movable frame portion 102 moves completely up to the upper side of the main body 101, that is, outward from the opening of the main body 101. Thereby, since the space | interval between a pair of soundproofing apparatuses 100 becomes large, the test vehicle 3 can be easily introduce | transduced and arrange | positioned on the chassis dynamometer 1. FIG. Then, the movable frame 102 is lowered as shown in FIGS. 3A and 4A in a state where the test vehicle 3 is disposed at a predetermined position on the chassis dynamometer 1.
[0022]
FIG. 5 schematically shows a state in which the soundproofing device 100 is installed on the test vehicle 3, that is, a lowered state of the movable frame portion 102. As shown in FIGS. 4A and 5, during the vehicle test, the movable frame portion 102 of the soundproof device 100 is driven by the test vehicle 3 with the test vehicle 3 disposed on the chassis dynamometer 1. It arrange | positions so that the circumference | surroundings of the ring | wheel 4 may be covered. At this time, the movable frame 102 of the soundproofing device 100 is in a lowered state, and the cushion material 102a contacts the vehicle body so as to cover the periphery of the drive wheels 4 of the test vehicle 3. That is, the cushion material 102 a is pressed against the vehicle body of the test vehicle 3 to be elastically deformed and comes into contact with the vehicle body of the test vehicle 3 without a gap. Thereby, the noise generated by the drive wheel 4 and the roller 2 during the test is confined in the soundproofing device 100 and absorbed by the sound absorbing material 104, and the surrounding noise level can be lowered.
[0023]
Next, the operation of the above soundproof device 100 during the experiment will be described. FIG. 6 is a plan view schematically showing the operation of the soundproofing device 100 at the start of the vehicle test. As shown in the figure, a pair of soundproofing devices 100 are arranged on both sides of the chassis dynamometer 1. Note that at the time before the start of the vehicle test, both the pair of soundproofing devices 100 are in the flipped-up state.
[0024]
First, when the operator drives the test vehicle 3 at an appropriate position indicated by a broken line 3x on the chassis dynamometer 1, that is, the driving wheel 4 (front wheel in this example) of the test vehicle 3 is a roller of the chassis dynamometer 1. 2 so as to be located on the top.
[0025]
Next, the movable frame portion 102 of each soundproof device 100 is lowered to a position where it comes into contact with the side surface of the test vehicle 3 as indicated by a broken line 102x. Thereby, the periphery of the left and right drive wheels 4 of the test vehicle 3 is covered with the soundproofing device 100. In this state, the drive wheel 4 of the test vehicle 3 is driven to perform a vehicle test.
[0026]
[Modification 1]
Next, a modified example of the sound absorbing material 104 housed inside the main body 101 will be described. In the above embodiment, the exposed surface of the sound absorbing material 104, that is, the surface facing the side of the vehicle is formed flat. On the other hand, irregularities can be formed on the exposed surface of the sound absorbing material 104. FIG. 7A shows an example of a vertical cross-sectional shape of a sound absorbing material having a flat exposed surface, and FIG. 7B shows an example of a vertical cross-sectional shape of the sound absorbing material having irregularities formed on the exposed surface.
[0027]
Basically, the sound absorbing effect of the sound absorbing material 104 depends on the surface area of the sound absorbing material 104, and the sound absorbing effect increases as the surface area increases. Therefore, the sound absorbing effect can be increased by forming irregularities on the exposed surface of the sound absorbing material 104. Further, by forming the unevenness, the thickness of the sound absorbing material 104 can be reduced. That is, since the sound absorption effect can be enhanced by forming the unevenness, as shown in FIG. 7, it is possible to obtain the same sound absorption effect even with a thinner sound absorption material.
[0028]
In addition, the example of FIG.7 (b) has shown the vertical cross section, and has shown the example by which an unevenness | corrugation is arranged in the perpendicular direction. Instead, the irregularities may be arranged in the horizontal direction, or may be an irregular shape in which a large number of protrusions are arranged on the exposed surface.
[0029]
Thus, the sound absorbing effect of the sound absorbing material can be enhanced by forming an uneven shape on the exposed surface of the sound absorbing material, that is, the surface facing the side surface of the test vehicle 3. Therefore, if the sound absorbing material has the same thickness, the sound absorbing effect can be enhanced by forming the unevenness. On the contrary, by forming irregularities, it is possible to reduce the thickness of the entire sound absorbing material while maintaining the same sound absorbing effect. Thereby, the depth of the main body 101 of the soundproofing device 100 can be reduced, and the soundproofing device 100 can be downsized.
[0030]
[Modification 2]
Since the above-described soundproofing device 100 has a structure in which the movable frame portion 102 covers the periphery of the drive wheel 4 that is a noise source, there is an effect of confining noise inside the soundproofing device 100. However, there is a tendency that frictional heat generated by the rotation of the drive wheel 4 is accumulated in the soundproofing device 100 accordingly. Therefore, when the vehicle test is performed with the soundproofing device 100 attached, the tire surface temperature may increase, which may adversely affect the fuel efficiency and emission of the vehicle test result.
[0031]
Therefore, as shown in FIG. 8, an air nozzle 105 is installed inside the main body 101 of the soundproofing device 100 to ventilate the inside of the soundproofing device 100 and form an air flow. By doing so, it is possible to suppress the temperature rise inside the soundproofing device, and it is possible to reduce or eliminate the influence on the fuel consumption and emission of the vehicle test result.
[0032]
【The invention's effect】
As described above, the soundproofing device for a chassis dynamometer according to the present invention includes a sound absorbing material inside and is configured so as to cover the driving wheel of the test vehicle with the movable frame portion, so that the vehicle test on the chassis dynamometer The noise generated by the rotation of the drive wheels and rollers can be reduced to a level that does not place a burden on the operator. In addition, since the movable frame part is constructed as a flip-up type, the movable frame part can be flipped up and retracted to the side, and the test vehicle can be smoothly introduced into the chassis dynamometer, and work efficiency can be improved. Rise.
[Brief description of the drawings]
FIG. 1 is a diagram schematically showing an overall configuration of a vehicle test apparatus to which a chassis dynamometer soundproofing device according to the present invention is applied.
FIG. 2 is a front view of the vehicle test apparatus shown in FIG.
FIG. 3 is a perspective view of the soundproofing device for a chassis dynamometer of the present invention, FIG. 3 (a) shows a lowered state of the movable frame portion, and FIG. 3 (b) shows a raised state of the movable frame portion.
4 is a horizontal sectional view taken along line II ′ of FIGS. 3 (a) and 3 (b). FIG.
FIG. 5 is a diagram schematically showing a state in which a chassis dynamometer soundproofing device is installed on a test vehicle.
FIG. 6 is a plan view schematically showing the operation of the chassis dynamometer soundproofing device at the start of a vehicle test.
FIG. 7 is an enlarged view of a modification of the sound absorbing material.
FIG. 8 is a view showing a modification in which an air nozzle is provided.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Chassis dynamometer 2 Roller 3 Test vehicle 4 Drive wheel 100 Soundproof apparatus 101 for chassis dynamometers Main body 102 Movable frame part 104 Sound absorbing material 105 Air nozzle 106 Handle 107 Opening part

Claims (4)

A main body having an opening disposed facing the side surface of the vehicle and containing a sound absorbing material therein;
A movable frame portion movable between a flip-up position that is an upper position of the main body and a lowered position that is a front position of the opening;
The movable frame portion is provided with a cushion material on a side surface facing the vehicle, and contacts the side surface of the vehicle so as to cover the periphery of the driving wheel of the vehicle through the cushion material at the lowered position. A soundproofing device for a chassis dynamometer. 2. The chassis dynamometer soundproofing device according to claim 1, wherein the movable frame portion is located behind the opening in the flip-up position. The soundproofing device for a chassis dynamometer according to claim 1 or 2, wherein the sound absorbing material is formed with irregularities on a surface on the opening side. The sound proof device for a chassis dynamometer according to any one of claims 1 to 3, further comprising an air nozzle that forms an air flow inside the main body.

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