JP3974453B2 - Engine intake structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an intake structure of an engine, and more particularly to a technique for reducing intake noise.
[0002]
[Prior art]
Conventionally, the intake noise of the engine has been suppressed. For example, it is a common practice to obtain a silencing effect by narrowing the opening at the end on the outside air side of a tubular member, such as an intake hose or intake pipe for taking in outside air, to reduce the diameter.
[0003]
[Problems to be solved by the invention]
However, in order to obtain a silencing effect by narrowing the opening of the intake hose or the like, it is necessary to adjust the diameter of the opening of the intake hose or the intake pipe according to the engine displacement or characteristics. For this reason, a plurality of hoses according to the engine displacement is required, and preparing a large number of hoses or pipes has a problem of increasing costs.
[0004]
[Means for Solving the Problems]
The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.
[0005]
In claim 1, in the intake hose (13) connected to the outside air side intake end of the air cleaner (12) of the engine (6), the intake passage is reduced to the outside air side intake opening of the intake hose (13). Insert an intake muffler pipe (16), create a plurality of intake muffler pipes (16) with different inner diameters and lengths, select one according to the type of engine to be installed, and fix it. When reducing low-frequency noise, an intake silencer pipe (16) with a narrow inner diameter (A1) is attached, and when reducing high-frequency noise, an intake silencer pipe (16 ') with a large inner diameter (A2). and the attachable, also short length of the intake silencer pipe (16) (B1) intake silencer pipe (16), or long (B2) and can be attached to the intake silencer pipe (16 '), also , Intake The silencer pipe (16) can be inserted into the intake hose (13) or extended to the outside of the intake hose (13), and the intake silencer pipe (16) has a small inner diameter. The intake silencer pipe (16 ') having a large inner diameter is continuously connected in series and can be installed in the intake hose (13), and the intake silencer pipe (16) is inserted into the intake hose (13). In the state, it is fastened and fixed by the hose band (17) from the outside of the intake hose (13).
[0006]
According to a second aspect of the present invention, an inclined portion (16a) is formed on the inner diameter of the opening on the outside air side of the intake silencer pipe (16).
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the invention will be described. FIG. 1 is a side view of a turning work vehicle having an engine intake structure according to the present invention, FIG. 2 is a plan view of the engine, FIG. 3 is a plan sectional view of an outside air side end of an intake hose, and FIG. FIG. 5 is a plan cross-sectional view of the outside air side end of the intake hose with the pipe inserted, FIG. 5 is a plan cross-sectional view of the outside air side end of the intake hose in the second embodiment, and FIG. FIG. 7 is a partial cross-sectional view of the intake hose according to the third embodiment.
[0008]
First, a schematic configuration of a turning work vehicle to which the engine intake structure according to the present invention is applied will be described. As shown in FIG. 1, the turning work vehicle supports the upper body 3 so as to be turnable via a swivel bearing 2 having an axis in the vertical direction at the center of the upper part of the traveling device 1 equipped with a pair of left and right crawler belts 1a. A blade 4 is disposed at one end of the front and rear of the traveling device 1 so as to be rotatable up and down. The upper body 3 includes an engine 6, a battery, a fuel tank, and the like placed on a revolving frame 5 and covered with a bonnet 7 to constitute an engine room. A steering part is arranged in the front part, a seat seat, a travel lever, a work operation lever, etc. are arranged in the steering part, and a canopy 8 is arranged above the bonnet 7. A work machine 9 is attached to the front end of the revolving frame 5.
[0009]
Next, the engine 6 will be described. As shown in FIG. 2, intake manifolds 10, 10... And exhaust manifolds 11, 11. The other end of the intake manifolds 10, 10... Is connected to an intake hose 13 via an air cleaner 12 and sucks outside air, and the other end of the exhaust manifolds 11, 11. Like to do. A cooling fan 15 is fixed to the output shaft or fan shaft of the engine 6. The outside air sucked from the intake hose 13 is cleaned by removing dust and the like by the air cleaner 12, passes through the intake manifolds 10, 10..., The intake valve, and flows into the cylinder. Burns with fuel. The combustion gas generated thereafter is discharged from the cylinder to the exhaust manifolds 11, 11..., Passes through the muffler 14, and is discharged to the outside.
[0010]
In such a configuration, as shown in FIG. 3, the present invention is configured such that a cylindrical intake silencer pipe 16 that reduces the intake passage is inserted inside the opening of the outside air side end portion of the intake hose 13. The intake silencer pipe 16 is made of metal or synthetic resin, and the intake silencer pipe 16 is tightened by the hose band 17 from the outside of the intake hose 13 while being inserted into the intake hose 13. It is configured to be fixed.
[0011]
As shown in FIGS. 3 and 4, a plurality of intake silencing pipes 16 having different inner diameters are prepared, and one of them is selected according to the type of engine to be attached, and the pipe 16 having the highest silencing effect is attached. It is. For example, when reducing low-frequency noise, the intake silencer pipe 16 with a narrow inner diameter A1 is attached, and when reducing high-frequency noise, the intake silencer pipe 16 'with a larger inner diameter A2 is attached.
[0012]
In addition, as shown in FIG. 4, the length B1 of the intake silencer pipe 16 can be changed to be longer or shorter like B2 to mute the sound. In this case, it can be inserted into the intake hose 13 or extended outward. Further, as shown in FIG. 7, it is possible to silence the intake muffler pipe 16 having a small inner diameter and the intake muffler pipe 16 ′ having a large inner diameter arranged in series in the intake hose 13. In this case, the order of connection may be reversed. Accordingly, it is possible to change the throttle diameter of the outside air side opening of the intake hose 13 without newly creating the intake hose 13 itself, and the intake hose formed from the same mold in engines with different displacements. 13 can be used, so that the manufacturing cost of the intake hose 13 can be reduced.
[0013]
Further, as shown in FIG. 5, a gentle inclined portion 16a or a round is formed in the inner diameter portion of the opening portion on the outside air side of the intake silencer pipe 16. With this configuration, as shown in FIG. 3, when the end portion on the outside air side of the intake silencer pipe 16 is cut in a plane, the sucked outside air is opened to the outside air side of the intake silencer pipe 16. When passing through the edge of the inner diameter, wind noise may occur. However, by configuring the inclined portion 16a or the round as in the present invention, it is possible to prevent the generation of wind noise by being sucked in smoothly and contribute to noise reduction.
[0014]
【The invention's effect】
Since the present invention is configured as described above, the following effects can be obtained.
[0015]
In the intake hose (13) connected to the outside air intake end of the air cleaner (12) of the engine (6), the intake passage is reduced to the outside air intake opening of the intake hose (13). The intake silencer pipe (16) is inserted, and a plurality of intake silencer pipes (16) having different inner diameters and lengths are created, and either one is selected and fixed according to the type of engine to be installed. In order to reduce low frequency noise, an intake silencer pipe (16) having a narrow inner diameter (A1) is attached, and in order to reduce high frequency noise, an intake silencer pipe (16 ') having a large inner diameter (A2) is attached. ), And the intake silencer pipe (16) having a short length (B1), the intake silencer pipe (16), and the long (B2) intake silencer pipe (16 ′), and the intake silencer pipe . Pipe (16) Inserted into the inside of the intake hose (13), or, attached to extend to the outside of the intake hose (13), also, the inner diameter smaller intake silencer pipe (16), the pipe large intake silencer inner diameter ( 16 ′) are continuously arranged in series and installed in the intake hose (13), and the intake hose (13) is inserted into the intake hose (13). The hose band (17) is fastened and fixed from the outside of the hose band (17), so the intake hose of the same shape is used in engines with different displacements and with different specifications, and an intake silencer pipe suitable for the engine is inserted into the intake pipe. Thus, the silencing effect can be enhanced simply by fixing, and the silencing measures can be taken at a low cost with a simple configuration. Further, even if the silencing characteristics fluctuate, the intake silencing pipe is simply replaced, so that it can be easily handled.
[0016]
According to the second aspect of the present invention, since the inclined portion is formed in the inside diameter of the opening on the outside air side of the intake silencer pipe, it is possible to prevent wind noise from being generated when outside air passes through the opening of the pipe. It is possible to enhance the silencing effect with a simple configuration.
[Brief description of the drawings]
FIG. 1 is a side view of a turning work vehicle having an engine intake structure of the present invention.
FIG. 2 is a plan view of the engine.
FIG. 3 is a plan sectional view of an outside air side end portion of an intake hose.
FIG. 4 is a plan sectional view of an outside air side end portion of an intake hose into which intake silencer pipes having different inner diameters are inserted.
5 is a plan sectional view of an outside air side end portion of an intake hose according to Embodiment 2. FIG.
6 is a partial cross-sectional view of a plan view of an intake hose in Embodiment 2. FIG.
7 is a partial cross-sectional view of a plan view of an intake hose according to Embodiment 3. FIG.
[Explanation of symbols]
12 Air cleaner 13 Intake hose 16 Intake silencer pipe 16a Inclined part

Claims (2)

In an intake hose connected to the outside air intake end of an engine air cleaner, an intake silencer pipe for reducing the intake passage is inserted into the outside air intake opening of the intake hose. Create multiple parts of different sizes, select one of them according to the type of engine to be installed, and fix it. If you want to reduce low-frequency noise, install an intake silencer pipe with a narrow inner diameter and high-frequency noise. was can be attached to the intake silencer pipe thick inner diameter in the case of reduction, also short intake silencer pipe lengths of the intake silencer pipe, or to allow attachment long intake silencer pipe, the intake silencer insert the use pipe to the interior side of the intake hose, or, to enable attachment to extend to the outside of the air intake hose, also small and the intake silencer pipe inner diameter, the inner diameter size The intake muffler pipe is continuously connected in series and can be installed in the intake hose, and with the intake muffler pipe inserted into the intake hose, tightened and fixed by a hose band from the outside of the intake hose. Characteristic engine intake structure.   2. The intake structure for an engine according to claim 1, wherein an inclined portion is formed in an inner diameter of an opening on the outside air side of the intake silencer pipe.

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