JPS6341543Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an engine noise reduction device formed in an engine enclosure device.

Conventionally, an enclosing device for an engine of an earthmoving vehicle or a construction machine, etc., has been formed by, for example, a hood 2, a side guard 4, a dart board 6, a radiator guard 8, a radiator grill 10, an under guard 12, etc., as shown in FIG. is common. A cooling system is established in the engine by discharging the air sucked through the opening of the hood or side guard to the front of the vehicle etc. from a cooling fan. However, this causes engine noise and other mechanical noise to be discharged from the front opening of the vehicle along with the exhaust air. Although completely enclosing the front of the engine compartment substantially eliminates these noises, sealing the engine compartment in this manner severely limits the engine cooling system and can cause overheating. Therefore, several methods have been proposed to obtain suitable noise attenuation characteristics at the same time without impairing the cooling characteristics of the engine. These methods include, for example, attaching a noise-reducing louver device to the front opening of the radiator guard, or attaching a radiator mask or radiator silencer to the front of the radiator guard to guide and discharge the noisy air discharged by the cooling fan to the top of the vehicle. This is an old method.

However, in the above-mentioned conventional method, the silencing effect of the silencing louver device alone is small, and simply discharging noisy air upwards of the vehicle like a radiator mask does not sufficiently attenuate the noise of the exhaust air.
Furthermore, there still remained problems in terms of noise countermeasures, such as the radiator silencer, which protrudes so much toward the front of the vehicle that it does not cover the entire vehicle.

The present invention has been made to eliminate the above-mentioned conventional drawbacks. Therefore, the present invention provides a noise reduction device for an engine in which cooling air is discharged from a radiator guard opening by a cooling fan. In addition to installing the device, a radiator silencer device is provided in front of the silencing louver device with a space between it and the radiator guard, covering almost the entire surface of the radiator guard, and cooling air is discharged from the upper part of the space. The silencing louver device includes a plurality of horizontal louvers with different cross-sectional shapes installed at an angle with respect to the flow of cooling air discharged by the cooling fan, and the louvers have a fixed angle or an adjustable angle with respect to the flow of cooling air. The radiator silencer device consists of a plate with a sound-absorbing material stretched on the inner surface, and the plate is a substantially vertical plane over the entire silencer device, or is recessed rearward from near the center to the bottom. It is characterized by the presence of

Hereinafter, the content of the present invention will be explained along with the embodiments shown in the attached drawings.

Figures 2 and 3 show the case where the present invention is applied to an engine enclosure device for an earthmoving vehicle. In the figures, 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.

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 8 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, and 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. As shown in FIG. 4, each horizontal louver is formed by surrounding a sound absorbing material 38 with a punching metal 40 having a sufficient aperture ratio.
installed at an angle to the flow of noisy air discharged by the Furthermore, as shown in FIG. 2, the louvers 6 have different cross-sectional shapes; the horizontal louver 36a directs noise air upward, the horizontal louver 36b directs noise air downward, and the wedge-shaped horizontal louver 36c directs noise air downward. Its shape allows some of the noisy air to be exhausted upwards and the rest downwards. The spacing and number of the louvers are determined for each vehicle so that the engine has sufficient ventilation to prevent overheating and to 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 12. It is smoothly combined with the sloping bottom surface of the The radiator silencer device is composed of an outer substantially planar plate 44 and a sound absorbing material 46 stretched over the entire inner surface of the plate 44. 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. The upper end of the space 42 formed by the present device 16 is an opening 50 through which noisy air is discharged to the outside of the vehicle. That's covered. The space section 42
The lower end is smoothly connected to the underguard 12 in order to guide a part 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 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 is a radiator, a tank, 66 is a hydraulic tank, 68 is an opening for an air cleaner, and 70 is an opening for a muffler.

Next, to describe the operation of the device in the above embodiment, cooling air is supplied from the outside of 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. Moreover, since the cross-sectional shapes of each louver 36 are different, the noise air is dispersed vertically.

Noise air that has passed 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
At the same time, the noise-absorbing material 46 muffles the noisy air, 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 guides the rest to the guideway 54 from the lower end entrance 60. . In addition,
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 the guide path, 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.

FIG. 5 shows another modification of the present invention, in which the space 42 formed by the radiator silencer device 16 is connected to the guideway 54 formed by the double-layered underguard 12. The outer plate 5 of the radiator guard near the
As shown in FIG.
An air exhaust port is formed at the bottom of the vehicle to pass through to the outside of the vehicle. As a result, (1) a part of the air recirculated to the engine room 26 is discharged outside the vehicle, which is advantageous in terms of preventing engine overheating, (2) the ventilation condition in the taxiway 54 is improved, and (3) ) Since the noise air discharged downward from the vehicle is absorbed by the ground, there is an advantage that the noise level does not substantially increase; There is an advantage that foreign substances such as soil and stones can be easily discharged by opening the plate 86.

FIG. 7 shows still another modification of the present invention, in which the plate 44 of the radiator silencer device 16 is recessed rearward from near the center to the bottom as shown in the figure. A part of the silencing louver device 14 and the under guard 12 are modified as shown in the figure. This avoids interference between the radiator silencer device 16 and the mounting frame of the working device attached to the front of the earthmoving vehicle.

Although not particularly shown, the horizontal louver 36 of the noise reduction louver device 14 is designed to provide a 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 is also possible to attach the horizontal louver 36 in a variable manner instead of a fixed manner.

Although not specifically mentioned, other configurations of the modified examples shown in FIGS. 5 to 7 above are shown in FIGS. 2 to 4.
The configuration can be the same as that of the embodiment shown in the figure.

As described above, according to the present invention, in an engine noise reduction device in which cooling air is discharged from a radiator guard opening by a cooling fan, a silencing louver device is installed in the radiator guard opening, and a silencing louver device is installed in front of the radiator guard opening. A radiator silencer device that covers almost the entire surface of the radiator guard is installed with a space between it and the silencing louver device, and cooling air is discharged from the top of the space, so that the cooling characteristics of the engine are not impaired. It is possible to sufficiently reduce the noise level of the exhaust air without causing any noise. In this case, the noisy air coming from the radiator guard opening was first reduced by a sound-deadening louver device, and then further reduced by a silencer device covered with sound-absorbing material, making it possible to obtain a large noise reduction effect. Moreover, since the flow of the noise air is guided by the plurality of horizontal louvers angled with respect to the flow of the air, the flow of the noise air discharged from the upper opening of the silencer device can be smoothly guided. Also,
The noisy air is forcibly dispersed vertically by multiple horizontal louvers with different cross-sectional shapes.
This dispersion not only provides a silencing effect, but also controls the flow of noisy air. Furthermore, in the present invention, the noisy air is substantially discharged only from the upper opening of the silencer device, so that no dust or the like is thrown up, and the workability is good. Furthermore, the plate on which the sound-absorbing material of the silencer device is stretched is a nearly vertical plane over the entire silencer device, or it is recessed rearward from near the center to the bottom, creating an excellent sense of unity with the vehicle. can be retained.

The device of this invention is applicable to engines other than earthmoving vehicles.
For example, it can be applied to an enclosing device for the engine of a construction machine. Further, in the above-described embodiment, a part of the exhaust air is particularly recirculated to the engine room through the guide path of the double-layered underguard, but the recirculation action of the exhaust air is not necessarily necessary.
Furthermore, 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 dual-structure cooling air intake duct and under guard shown here.

[Brief explanation of the drawing]

FIG. 1 is a side view of an earthmoving vehicle equipped with a conventional engine enclosure device, FIG. 2 is a side view of the internal structure of an embodiment of the engine enclosure device equipped with the engine noise reduction device according to the present invention, and FIG. 3 is a side view of an earthmoving vehicle equipped with a conventional engine enclosure device. is a partially omitted and partially sectional plan view of the device shown in FIG. 2, FIG. 4 is a sectional view of the louver, FIG. 5 is a partial side view showing a modification of the device of the present invention, and FIG. 7 is a view taken along the line - in FIG. 5, and FIG. 7 is a view similar to FIG. 2 showing a further modification of the device of the present invention. 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...
... Louver, 42 ... Space section, 44 ... Plate,
46... Sound absorbing material, 50... Opening, 54... Taxiway, 56, 58... Plate, 60... Inlet, 6
2...exit, 84...exhaust port.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) In an engine noise reduction device in which cooling air is discharged from a radiator guard opening by a cooling fan, a noise reduction louver device is installed in the radiator guard opening, and a noise reduction device is installed in front of the noise reduction louver device. A radiator silencer device that covers almost the entire surface of the radiator guard is provided with a space between it and the silencing louver device, and cooling air is discharged from the upper part of the space,
The silencing louver device includes a plurality of louvers with different cross-sectional shapes installed at an angle with respect to the flow of cooling air discharged by the cooling fan, and the louvers have a fixed angle or an adjustable angle with respect to the flow of cooling air. The radiator silencer device consists of a plate with a sound absorbing material stretched on the inner surface, and the plate is a substantially vertical plane over the entire silencer device, or is recessed rearward from near the center to the bottom. An engine noise reduction device featuring: (2) The device according to item 1, wherein a vertical partition plate is provided on the inner surface of the radiator silencer device to partition the space into a plurality of rooms.