JP2543669Y2 - Intake sound reduction device for soundproof engine working machine - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intake noise reduction device for a soundproof engine working machine such as a generator with an engine.

[0002]

2. Description of the Related Art Conventionally, a technology provided with an intake silencer as an intake noise reduction device in a soundproof engine working machine is known. For example, the actual opening 62-2
This is like the technique described in Japanese Patent No. 1448.

[0003]

However, in the prior art, the intake silencer is formed as a separate chamber inside the soundproof box, and the entire soundproof box is enlarged to constitute the intake silencer. There was a need. An object of the present invention is to make it possible to store an intake silencer inside a compact soundproof box.

[0004]

The problems to be solved by the present invention are as described above. Next, means for solving the problems will be described. Engine E intake manifold M and air cleaner 7
An intake silencer 8 is interposed in the intake passage between
An elastic material pipe 9 connects between the cleaner 7 and the intake silencer 8.
And the lower communication port 16 of the intake silencer 8 is sucked.
The air manifold M is disposed above the front end communication portion 17 and
In a configuration in which the intake passage between the
In the soundproof box constituting the outer periphery of the gin working machine,
The air cleaner 7 and the exhaust pipe are located in the upper part of the engine E.
14 and an intake silencer 8 in the space between them.
Is placed .

[0005]

Next, the operation of the present invention will be described with reference to FIGS. When the cavity resonance frequency of the volume of the air cleaner 7 resonates with the fundamental vibration frequency of the intake system during operation of the output voltage frequency of 50 Hz / 60 Hz, a low frequency is generated, which causes noise. This low frequency also excites the bonnet component panel from the inside, which significantly increases noise. In the case of only the conventional air cleaner 7,
As shown in FIG. 6, a cavity resonance frequency was generated due to the volume of the air cleaner. Particularly, since the cavity resonance frequency was close to the intake system vibration frequency of 60 Hz, both were easy to resonate. On the other hand, by interposing the intake silencer 8 as in the present invention, a cavity resonance frequency is generated in a volume obtained by adding the air cleaner 7 and the intake silencer 8, and this frequency is higher than 60 Hz as shown in FIG. And the resonance of both will disappear,
It was possible to reduce the noise.

[0006]

Next, an embodiment of the present invention will be described. 1 is a front view showing a main part of an intake sound reducing device in a soundproof engine working machine, FIG. 2 is a plan perspective view of the soundproof engine working machine, and FIG. FIG. 4 is an enlarged side view showing a mounting portion of the intake silencer 8 and the intake manifold M. FIG. 5 is a drawing showing a state of generation of a cavity resonance frequency when the intake silencer 8 is provided.
FIG. 3 is a diagram showing a state of generation of a cavity resonance frequency when the intake silencer 8 is not provided.

This will be described with reference to FIGS. 1, 2 and 3. In a soundproof engine working machine, the outer wall is configured as a soundproof wall,
Engine E, clutch housing 11 and generator D inside
Are integrally configured. The power output by the generator D can be taken out of the terminal box 2. An operation panel 1 is arranged above the terminal box 2 and the engine E
And the operation of the generator D can be performed. A radiator fan 13 and a radiator 12 are arranged at a position on the right side of the engine E, and a silencing muffler 6 is arranged on the left side of the radiator 12.

An exhaust pipe 14 connects the exhaust manifold of the engine E to the muffler 6.
As shown in FIG. 2, the exhaust pipe 14 is constituted by metal exhaust pipes 14b and 14c and an elastic material pipe 14a, so that vibration of the engine E is not transmitted to the muffler 6. An air cleaner 7 is horizontally arranged near the front of the soundproof engine working machine, and an intake silencer 8 is arranged between the air cleaner 7 and the exhaust pipe 14 at a position above the intake manifold M of the engine E. ing. Then, the portion of the right side soundproof wall 16 below the intake silencer 8 is connected to the front end communication portion 17 of the intake manifold M by the connector 15.

Next, a connection state between the intake silencer 8 and the intake manifold M will be described with reference to FIG. The intake manifold M is fixed to the cylinder head of the engine E, and is branched according to the number of cylinders of the engine E. However, the front end communication portion 17 is provided at one position, and the air taken in from the front end communication portion 17 is branched into the respective cylinder portions. The intake silencer 8 is fixed to the intake manifold M by an intake silencer fixing band 18 protruding from the intake manifold M. The air cleaner 7 and the intake silencer 8 are connected by an elastic pipe 9. By connecting with the elastic material pipe 9, transmission of vibration between the intake silencer 8 and the air cleaner 7 can be shielded, so that noise can also be avoided.

[0010]

[Effects of the Invention] Since the present invention is configured as described above, the following effects can be obtained. First, since the intake silencer 8 is interposed in addition to the air cleaner 7, the capacity of the air cleaner can be increased. It is possible to dump to the frequency exceeding. As a result, the fundamental vibration frequency of the intake system and the cavity resonance frequency resonate, and low-frequency vibration is not generated, so that the soundproof wall does not vibrate at a low frequency from the inside. Second, it is necessary to increase the size of the hood of the soundproof engine working machine by adding the intake silencer 8. In the present invention, however, the intake silencer 8 is connected to the air cleaner 7 and the exhaust pipe 1.
4, the intake silencer 8 can be easily attached without increasing the volume of the hood, since the intake manifold M is mounted above the intake manifold M of the engine E. .

[Brief description of the drawings]

FIG. 1 is a front view showing a main part of an intake noise reducing device in a soundproof engine working machine.

FIG. 2 is a plan perspective view of the soundproof engine working machine.

FIG. 3 is a side perspective view of the sound deadening muffler 6 as viewed from the same side.

FIG. 4 is an enlarged side view showing a mounting portion of the intake silencer 8 and the intake manifold M.

FIG. 5 is a diagram showing a state of occurrence of a cavity resonance frequency when an intake silencer 8 is laid.

FIG. 6 is a diagram showing a state of generation of a cavity resonance frequency when there is no intake silencer 8;

[Explanation of symbols]

 M Intake manifold 1 Operation panel 2 Terminal box 3 Fuel gauge 4 Fuel tank 5 Battery 6 Silence muffler 7 Air cleaner 8 Intake silencer 9 Elastic material pipe 14 Exhaust pipe

Claims (1)

(57) [Scope of request for utility model registration] 1. An intake manifold M of an engine E and air.
An intake silencer 8 is interposed in the intake passage between the cleaner 7
An elastic material is provided between the air cleaner 7 and the intake silencer 8.
The lower communication port of the intake silencer 8 is connected by a pipe 9.
16 above the front end communication portion 17 of the intake manifold M
In the configuration in which the intake passage is connected between the two,
Inside the soundproof box that constitutes the outer periphery of the soundproof engine working machine
And an air cleaner 7 at a position above the engine E.
And an exhaust pipe 14 are arranged in the space between them.
An intake sound reducing device for a soundproof engine working machine, wherein a sensor 8 is disposed .