JPS6225852B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a noise attenuation device, and more particularly to a noise attenuation device that is attached to an engine enclosure to reduce engine noise.

Conventionally, in order to appropriately reduce engine noise without impairing the cooling characteristics of the engine in earthmoving vehicles or construction machinery, etc., it has not been possible to install a noise attenuation device equipped with a plurality of silencing louvers at the opening of the engine enclosure device. Are known. However, the conventional noise attenuation device simply has a silencing louver disposed in front of the flow of noisy air, and therefore has the disadvantage that the noise prevention effect is small. In particular, the effect of preventing noise to the front of the vehicle and the surrounding area is small. In addition, since conventional noise attenuating devices with silencing louvers have a structure that does not allow adjustment of the amount of noisy air emitted, noise attenuating devices with louvers are ideal for changes in usage environment such as season of use and location of use. The disadvantage is that it is not possible to obtain a sufficient flow of cooling air.

The present invention has been made in order to eliminate the above-mentioned conventional drawbacks, and for this reason, the present invention includes a radiator silencer device that guides the noisy air discharged from the opening in front of the opening of the radiator guard upwardly. A noise attenuation device mounted on an engine enclosure device comprising a double-structured underguard for guiding part of the noisy air discharged from the opening into the engine compartment, the radiator opening including a plurality of horizontal louvers attached at intervals vertically to a frame member attached to the frame member,
The horizontal louver is characterized in that it has a cross-sectional shape that vertically disperses the noisy air passing through the noise attenuation device.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The content of the present invention will be described below with reference to embodiments shown in the accompanying drawings.

Figures 1 and 2 show the case where the present invention is applied to an engine enclosure device for an earthmoving vehicle, in which 1 is an engine, 3 is a cooling fan, 5 is a radiator core, 2 is a hood, and 4 is a side guard,
6 is the dash board, 8 is the radiator guard, 1
2 is under guard, 14 is radiator guard 8
16 indicates a silencer device assembled to the radiator guard 8 in front of the silencing louver device 14, which constitutes the noise attenuation device according to the present invention.

As shown in the figure, the hood 2 has a double structure including an outer plate 18 and an inner plate 20, and an intake duct 22 is formed between the outer plate 18 and the inner plate 20. The duct 2
The front end of 2 is closed by a plate 24, and the rear end is an opening 28 communicating with an engine room 26. Near the front end of the duct 22, the left and right corners of the hood 2 are formed of punched metal 30, and the punched metal forms an intake port 32 for sucking cooling air into the duct 22 from outside the vehicle. A sound absorbing material 34 is stretched over almost the entire inner and outer surfaces of the duct 22.

The silencing louver device 14 includes a plurality of horizontal louvers 36 that are vertically spaced apart and provided in parallel.
These louvers 36 are attached to a fixed frame (not shown), and the fixed frame is detachably attached to the opening 9 of the radiator guard 8. Each horizontal louver has a sound absorbing material 3 as shown in FIG.
8 is surrounded by a punching metal 40 made of a porous material or member having a sufficient aperture ratio, and is installed at a certain angle with respect to the flow of noisy air discharged by the cooling fan 3. In addition, as shown in FIG. 1, the louvers 36 have different cross-sectional shapes; the horizontal louver 36a directs noise air upwards, the horizontal louver 36b directs noise air downwards, and the wedge-shaped horizontal louver 3
6c has a shape that allows part of the noisy air to be discharged upward and the rest downward. The spacing and number of the louvers are determined for each vehicle so that the engine has enough ventilation to prevent overheating and can exhibit a sufficient sound absorption effect.

The radiator silencer device 16 is installed slightly separated from the louver device 14 so as to form a space 42 between the radiator silencer device 16 and the louver device 14. The radiator silencer device 16 has a width that is almost the same as the width of the radiator guard 8 so as to cover almost the entire surface of the radiator guard 8, its upper end extends to the same height as the hood 2, and its lower end extends to the under guard. It is smoothly connected to the 12 slanted bottom surfaces. The radiator silencer device includes an outer substantially planar plate 44 and a sound absorbing material 4 stretched over the entire inner surface of the plate 44.
6. A plurality (1 to 3) of vertical partition plates 48 are installed to divide the space 42 formed by the device 16, the radiator guard 8, and the silencing louver device 14 into several rooms to enhance the silencing effect. It is detachably attached to the outer plate 44. The partition plate 48 is formed by surrounding a sound absorbing material with punched metal having a sufficient aperture ratio. Space portion 4 formed by this device 16
The upper end of 2 is an opening 5 through which noisy air is discharged to the outside of the vehicle.
0, and the opening 50 is covered with a punched metal or the like 52 having a sufficient aperture ratio to prevent foreign matter from entering from outside the vehicle. The space section 42
The lower end of the noisy air is smoothly connected to the underguard 12 in order to guide a portion of the noise air to the guide path 54 formed by the double-layered underguard 12.

The under guard 12 has a double structure with an inner plate 56 and an outer plate 58 to form a guideway 54. The inlet 60 of the guideway 54 is connected to the lower end of the upper space 42, and the outlet 62 is connected to the engine. It opens into room 26. A sound absorbing material may be provided on the inner and outer surfaces of the guideway 54 to enhance the sound absorbing effect.

In the figure, 64 indicates a radiator tank, 66 indicates a hydraulic tank, 68 indicates an opening for an air cleaner, and 70 indicates an opening for a muffler.

Next, to describe the operation of the above-described embodiment, cooling air is supplied from outside the vehicle to the duct 22 through the cooling air intake port 32 of the hood 2 by the blowing action of the cooling fan 3.
through the duct 22 and into the opening 28.
It is sucked into the engine room 26. Since the opening 28 is separated from the cooling air intake port 32 by the duct 22 covered with a sound absorbing material 34, the noise inside the engine room 26 is absorbed by the sound absorbing material 34 while being dissipated to the outside of the vehicle through the duct 22. and reduced. Since the sound absorbing material is stretched over almost the entire surface of the duct 22, a large sound absorbing area can be obtained and a good sound absorbing effect can be obtained. In addition, by providing sound absorbing material on the inner and outer surfaces of the duct 22 in this way, it is possible to reduce the reverberation of noise on the iron plate surface, and also to prevent the occurrence of chatter noise due to the vibration of the plates 18 and 20. can.

Cooling air sucked into the engine room 26 through the opening 28 passes around the engine 1 and is discharged to the radiator core 5 by the cooling fan 3. Since the gap between the radiator core 5 and the exhaust gas 72 and 74 is closed, most of the noisy air discharged by the cooling fan 3 flows through the radiator core 5.
and is guided to the silencing louver device 14.

The silencing louver device 14 has a sound absorbing effect on the noisy air discharged by the cooling fan 3, but as described above, since each louver 36 is angled with respect to the flow of the noisy air, a good sound absorbing effect cannot be obtained. Furthermore, since the louvers 6 have different cross-sectional shapes, the noisy air is dispersed vertically, resulting in an excellent noise prevention effect.

Noise air passing through the silencing louver device 14 is guided to a radiator silencer device 16 in front of the louver device 14. The radiator silencer device 16 muffles the noisy air with the sound absorbing material 46, guides the noisy air along the space 42, discharges a part of it to the outside of the vehicle from the upper opening 50, and discharges the rest from the lower end entrance 60. It leads to the taxiway 54. The vertical dispersion of the noisy air by the silencing louver device facilitates the discharge of the noisy air from the upper opening 50 and the guidance to the guide path 54. At this time, the sound absorbing material 46 prevents the plate 44 from chattering noise caused by collision of noisy air or vibration of the vehicle body.

The noise air guided into the guideway 54 from the space 42 is introduced into the engine room 26 from the outlet 62 through the guideway 54, where it is combined with the cooling air taken in from the cooling air intake port 32 of the hood 2. Mix again from the cooling fan 3 to the radiator core 5,
It is circulated through the silencing louver device 14 and the radiator silencer device 16. As a result, part of the noisy air discharged from the radiator silencer device 16 to the outside of the vehicle can be recirculated back into the engine room 26 through this device, thereby reducing the noise discharged to the outside of the vehicle. Further, since the under guard 12 has a double structure, there is an advantage that noise in the engine room is difficult to pass through to the outside of the vehicle.

Although not particularly shown, the sound deadening louver device 1
The horizontal louver 36 shown in No. 4 is installed in a non-fixed manner in order to provide the louver angle that provides the most appropriate flow of noise air in response to changes in the environment such as the season of use of the vehicle and the location of use. It can also be variable.

As described above, according to the present invention, since the noisy air discharged outside the engine enclosure device can be dispersed vertically, an excellent noise prevention effect can be obtained without increasing the sound volume only in a specific direction. In particular, the noise attenuating device of the present invention works in conjunction with the radiator silencer device to double attenuate the noise air discharged from the opening of the radiator guard, and also discharges the noisy air upward. And the noise level to the surrounding area can be significantly reduced. In addition, by dispersing the noisy air from the radiator guard opening vertically using horizontal louvers, the flow of the noisy air discharged from the upper opening of the radiator silencer device and the noisy air circulating into the engine room via the under guard is reduced. We can guide you smoothly. By making it possible to change the louver angle of the horizontal louver as described above, or by changing the cross-sectional shape of the louver, it is possible to respond to changes in the usage environment such as the frequency of use of the noise attenuation device and the place of use. The flow rate of the noisy air discharged from the radiator silencer device and the noisy air circulated into the engine compartment via the under guard can be optimally controlled.

The device of the present invention can also be applied to an engine enclosure device having a general structure that does not have the special structure of the double-structured cooling air intake duct shown in the embodiment. The device of the present invention can also be applied to engines other than earthmoving vehicles, such as engine enclosure devices for construction machinery.

[Brief explanation of the drawing]

FIG. 1 is a side view of the internal structure of an embodiment of the engine enclosure device according to the present invention, FIG. 2 is a partially omitted plan view of the device shown in FIG. It is a sectional view of a louver. 1... Engine, 2... Hood, 3... Cooling fan, 4... Side guard, 5... Radiator core, 8... Radiator guard, 12... Under guard, 14... Sound deadening louver device, 16... Radiator silencer device, 22... duct, 26...
...engine room, 28...opening, 32...intake port, 34...sound absorbing material, 36a, 36b, 36c...
...Luba, 42...Space department.

Claims (1)

[Scope of Claims] 1. A radiator silencer device in front of the opening of the radiator guard that guides the noisy air discharged from the opening to be discharged upward, and a radiator silencer device that guides the noisy air discharged from the opening to the engine. A noise attenuation device attached to an engine enclosure device equipped with a double-layered underguard for guiding circulation into a room, the device being attached to a frame member attached to the radiator opening at vertical intervals. 1. A noise attenuation device comprising a plurality of horizontal louvers arranged in a horizontal direction, the horizontal louvers having a cross-sectional shape that vertically disperses noisy air passing through the noise attenuation device. 2. The device of claim 1, wherein the horizontal louvers include horizontal louvers of different cross-sectional shapes including upwardly and downwardly sloping surfaces, respectively. 3. The apparatus of claim 2, wherein the horizontal louver further includes a horizontal louver having a wedge-shaped cross section. 4. The device according to item 1, wherein each of the horizontal louvers is attached to the frame member so that the angle can be fixed or adjusted. 5. The surface of each of the horizontal louvers is surrounded by a porous material or member having a sufficient aperture ratio, and a sound absorbing material is formed inside the material, and the material is detachably attached so as to be replaceable. Apparatus according to paragraph 1.