Exhaust structure for soundproof engine-driven work equipment

Abstract

To reduce leakage of noise via an air exhaust port without lowering cooling performance of a soundproof type engine-driven work machine.SOLUTION: In an air exhaust chamber 30b, an upper obstacle plate 61 which projects horizontally from an upper end position T of a core 54b of a radiator 54 and lower obstacle plates 62 (621, 622) which project horizontally from a height position below the upper obstacle plate 61 and above a height-directional center position M of the core 54b of the radiator 54 are provided, and the upper obstacle plate 61 and lower obstacle plates 621, 622 are arranged in a course of noise of an engine room 30a extending to an exhaust port 35 via the radiator 54 so as to attenuate the noise. The upper obstacle plate 61 and lower obstacle plates 621, 622 do not block passage of cooling air flowing to the exhaust port 35 via the radiator 54, and consequently the noise can be reduced without lowering cooling performance of an engine-driven work machine 1.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to the exhaust section structure of a soundproof engine-driven working machine which comprises a working machine main body such as a compressor main body or a generator main body, the engine which drives it, and other necessary equipment housed within a soundproof box, and more specifically, to the exhaust section structure of a soundproof engine-driven working machine which makes it possible to reduce noise leakage generated within the soundproof box via the exhaust section of the soundproof engine-driven working machine. [Background technology]

[0002] Engine-driven work machines, such as compressors and generators that have an engine as a driving source, are configured as packaged soundproof work machines, with the engine, work machine body, and other components housed in a soundproof box to prevent noise from escaping outside the machine during operation and to make them easier to transport and install.

[0003] An example of the construction of such a soundproof engine-driven working machine 300 is shown in FIG.

[0004] The soundproof box 310 of the soundproof engine-driven work machine 300 shown in Figure 9 is composed of a base 320 on which the engine 351, the work machine body 352 such as the compressor body and generator body driven by the engine 351, and other components of the engine-driven work machine are placed, and a soundproof case 330 that covers the base 320 on which these components are placed, and a space is formed within the soundproof case 330 to accommodate the components of the engine-driven work machine.

[0005] The space within this soundproof case 330 is divided into front and rear in the longitudinal direction of the soundproof box 310 by a partition wall 312 erected vertically on the base 320, with one of these chambers forming an engine chamber 330a which houses the engine 351 and the work machine main body 352, and the other chamber forming an exhaust chamber 330b which communicates with the outside of the machine via an exhaust port 335 provided in the top panel 334.

[0006] The engine compartment 330a and the exhaust chamber 330b are connected through a communication port (not shown) provided in the central part of the partition wall 312, and a radiator 354 for the engine 351 is arranged at this communication port. A cooling fan 355 is provided to introduce cooling air to the radiator 354. When the cooling fan 355 generates cooling air from the engine compartment 330a toward the exhaust chamber 330b, the cooling air that has passed through the radiator 354 is introduced into the exhaust chamber 330b, and the cooling air introduced into the exhaust chamber 330b is discharged outside the aircraft through the exhaust port 335 provided in the top panel 334.

[0007] In addition, an air intake 327 for introducing outside air is provided on the side panel 333 of the soundproof case 330. When the cooling fan 355 is rotated to generate a flow of cooling air from the engine compartment 330a toward the exhaust compartment 330b, negative pressure is created inside the engine compartment 330a, so that outside air is introduced from outside the aircraft into the engine compartment 330a through the air intake 327 as cooling air.

[0008] In this way, the side panel 333 and top panel 334 of the soundproof engine-driven work machine 300 are provided with air intake 327 and air exhaust 335, and since the space inside the soundproof box 310 is connected to the outside of the machine, noise generated inside the soundproof box 310 can leak out of the machine through openings such as the air intake 327 and air exhaust 335.

[0009] For this reason, various soundproofing structures have been proposed to prevent noise generated inside the soundproof box 310 from leaking outside the aircraft through such openings.

[0010] As an example of such a soundproofing structure, Patent Document 1 listed below discloses a duct 360 shown in FIG. 10 attached to the inside of an air intake 327 provided in a side panel 333 of a soundproof box 310, thereby ensuring the introduction of outside air into the soundproof box 310 via the air intake 327 while preventing noise generated within the engine compartment 330a from leaking directly outside the aircraft via the air intake 327.

[0011] In addition, in Patent Document 2 listed below, as shown in FIG. 11, an exhaust port 335 connecting the exhaust chamber 330b with the outside of the machine is provided in the rear panel 332 of the soundproof box 310, and a louver 361 is attached to this exhaust port 335, thereby reducing noise leaking outside the machine through the exhaust port 335 and preventing rainwater from entering through the exhaust port 335. [Prior art documents] [Patent documents]

[0012] [Patent Document 1] JP 2009-121409 A [Patent Document 2] JP 2011-241695 A Summary of the Invention [Problem to be solved by the invention]

[0013] As described above, it has been proposed to attach ducts 360 and louvers 361 as a soundproofing measure for openings such as intake port 327 and exhaust port 335 provided in soundproof box 310.

[0014] However, if a duct 360 or louvers 361 are provided at the exhaust port 335 communicating with the aforementioned exhaust chamber 330b, the cooling air will not flow out as easily as in a configuration in which the duct 360 or louvers 361 is not provided at the exhaust port 335, and the amount of cooling air passing through the radiator 354 will decrease, resulting in a decrease in the cooling performance of the engine 351, which will affect the heat balance of the soundproof engine-driven work machine 300.

[0015] For this reason, with respect to the exhaust port 335 which is connected to the exhaust chamber 330b, soundproofing measures such as the installation of ducts 360 or louvers 361 are not taken, and noise reduction is generally dealt with mainly by doubling the soundproof case 330 or by increasing the size of the silencer of the engine 351.

[0016] However, soundproofing measures such as doubling the soundproof case 330 or using larger mufflers are very large-scale and costly, and taking such soundproofing measures would reduce the price competitiveness of soundproof engine-driven work machines in the market.

[0017] Therefore, there is a demand for soundproofing measures that are simpler in structure, can increase the soundproofing effect at low cost, and yet do not reduce the cooling performance of soundproof engine-driven work machines or can improve the cooling performance.

[0018] Therefore, the present invention has been made to eliminate the drawbacks of the above-mentioned conventional technology, and aims to provide an exhaust structure for a soundproof engine-driven work machine which has a relatively simple structure, can be realized at low cost, and can reduce the leakage of noise through an exhaust port provided in the top panel of the soundproof box and connected to the exhaust chamber, without reducing the cooling performance of the soundproof engine-driven work machine or capable of improving the cooling performance. [Means for solving the problem]

[0019] The means for solving the problems are described below together with the reference numerals used in the description of the embodiment of the invention. The reference numerals are used to clarify the correspondence between the description of the claims and the description of the embodiment of the invention, and needless to say, are not used to restrict the interpretation of the technical scope of the present invention.

[0020] In order to achieve the above object, the exhaust structure of the soundproof engine-driven working machine 1 of the present invention is as follows: A soundproof engine-driven working machine in which the inside of a soundproof box 10 is divided into two compartments by a partition wall 12 erected vertically, one compartment being an engine compartment 30a in which an engine 51 and a working machine body (not shown) are housed, and the other compartment being an exhaust chamber 30b communicating with the engine compartment 30a via a communication port (not shown) provided in the partition wall 12, an exhaust port 35 communicating with the outside of the machine is provided in a top panel 34 at the position where the exhaust chamber 30b is formed, a cooling fan 55 is provided for generating cooling air from the engine compartment 30a to the exhaust chamber 30b, and a radiator 54 for the engine 51 is disposed at the position where the communication port provided in the partition wall 12 is formed, and an exhaust section 40 for discharging the cooling air after heat exchange in the radiator 54 to the outside of the machine is formed in the section from the exhaust chamber 30b to the exhaust port 35, An upper baffle plate 61 having a rectangular shape in plan view is disposed horizontally in the exhaust chamber 30b, with one side 61a in contact with or close to the side surface of the radiator 54 on the exhaust chamber 30b side at a height position equal to or higher than the upper end position T of the core 54b of the radiator 54, and the other side 61b opposite to the one side 61a extending to a position partially overlapping with the exhaust port 35 in a plan view. , A lower baffle plate 62 (621, 622) having a rectangular shape in a plan view with one side 621a, 622a in contact with or close to the side surface of the core 54b of the radiator 54 on the side of the exhaust chamber 30b at a height position above the center position M in the height direction of the core 54b of the radiator 54 is disposed horizontally in the exhaust chamber 30b, The interval (W2a, W2b) between the one side 621a, 622a of the lower baffle plate 62 (621, 622) and the other side 621b, 622b facing the one side 621a, 622b is formed shorter than the interval W1 between the one side 61a and the other side 61b of the upper baffle plate 61. (Claim 1: see Figs. 1 to 5).

[0022] A plurality of the lower baffle plates 62 (621, 622) may be provided and arranged vertically at intervals, and the intervals W2a, W2b between the one side 621a, 622a and the other side 621b, 622b of the lower baffle plates 62 (621, 622) may be made shorter as the lower one is arranged (see claims). 2 (See Figure 4).

[0023] It is preferable to attach a sound insulating material (not shown) such as urethane foam to the upper baffle plate 61 and / or the lower baffle plate 62 (621, 622) (see claims). 3 ).

[0024] It is preferable to provide an upwardly protruding flange 63 on each of the sides 61a, 621a, 622a of the upper baffle plate 61 and the lower baffle plate 62 (621, 622) (see claims). 4 (See Figure 4).

[0025] Furthermore, it is preferable to provide a downwardly protruding flange 64 on the other sides 61b, 621b, 622b of the upper baffle plate 61 and the lower baffle plate 62 (621, 622) (see claims). 5 (See Figure 4). Effect of the Invention

[0026] With the configuration of the present invention described above, in a soundproof engine-driven work machine 1 equipped with the exhaust section structure of the present invention, it is possible to suppress the leakage of noise through the exhaust port 35 without reducing the cooling performance of the soundproof engine-driven work machine 1.

[0027] In particular, in a configuration in which a lower baffle plate 62 is provided, or more preferably in which multiple lower baffle plates 62 (621, 622) are provided and the spacing W2a, W2b between one side 621a, 622a and the other side 621b, 622b of the lower baffle plates 621, 622 becomes shorter the further down the plate goes, the imbalance in the amount of cooling air passing above and below the radiator 54 is corrected and made uniform, thereby improving the cooling performance of the soundproof engine-driven work machine 1.

[0028] In a configuration in which sound-proofing material (not shown) such as urethane foam is attached to the upper baffle plate 61 and / or the lower baffle plate 62 (621, 622), the effect of preventing noise leakage can be further improved.

[0029] Furthermore, by providing the upper baffle plate 61 and lower baffle plate 62 (621, 622) described above, when the soundproof engine-driven work machine 1 is stopped, rainwater blown in through the exhaust port 35 is less likely to fall on the core 54b of the radiator 54. As a result, rainwater that passes through the gaps between the fins provided on the core 54b of the radiator 54 can be effectively prevented from entering the engine compartment 30a.

[0030] In this case, by providing an upwardly protruding flange 63 on one side 61a, 621a, 622a of the upper baffle plate 61 and the lower baffle plate 62 (621, 622), rainwater falling on the upper baffle plate 61 and the lower baffle plate 62 (621, 622) can be effectively prevented from falling onto the core 54b side of the radiator 54.

[0031] In addition, by providing a downwardly protruding flange 64 on the other sides 61b, 621b, 622b of the upper baffle plate 61 and the lower baffle plate 62 (621, 622), not only can the strength of the upper baffle plate 61 and the lower baffle plate 62 (621, 622) be improved, but rainwater falling on the upper baffle plate 61 and the lower baffle plate 62 (621, 622) can be made to fall from the other sides 61b, 621b, 622b without accumulating on the upper baffle plate 61 and the lower baffle plate 62 (621, 622). [Brief description of the drawings]

[0032] [Figure 1] 1 is a perspective view of a soundproof engine-driven working machine equipped with an exhaust structure of the present invention; [Diagram 2] 1A is a side view of a soundproof engine-driven working machine equipped with the exhaust structure of the present invention, and FIG. 1B is a plan view of the exhaust port portion. [Diagram 3] FIG. 2 is an explanatory diagram of an exhaust section of a soundproof engine-driven working machine. [Figure 4] An explanatory diagram of the upper and lower baffles. [Diagram 5] FIG. 2 is a perspective view of a baffle unit equipped with an upper baffle and a lower baffle. [Figure 6] 1A and 1B are explanatory diagrams of the sound insulation effect in the exhaust structure of the present invention, where (A) is an explanatory diagram of the sound insulation effect against straight sound from a noise source NS, and (B) is an explanatory diagram of the sound insulation effect against noise that has passed through a radiator. [Figure 7] An explanatory diagram showing the flow of cooling air in the exhaust section, where (A) is an exhaust section without upper and lower baffles, and (B) is an exhaust section with upper and lower baffles. [Figure 8] FIG. 4 is an explanatory diagram of the effect of preventing rainwater from entering the exhaust section of the present invention. [Figure 9] FIG. 1 is an explanatory diagram showing a configuration example of a soundproof engine-driven working machine (conventional). [Figure 10] An explanatory diagram of a duct installed at the intake port of a soundproof engine-driven working machine (corresponding to FIG. 9(C) of Patent Document 1). [Figure 11] FIG. 5 is an explanatory diagram of the soundproofing structure (soundproofing using louvers) of an exhaust port of a soundproof engine-driven working machine (corresponding to FIG. 5 of Patent Document 2). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0033] The configuration of a soundproof engine-driven working machine 1 equipped with an exhaust section structure of the present invention will be described below with reference to the attached drawings.

[0034] [Overall configuration of soundproof engine-driven working machine] Reference numeral 1 in Figs. 1 and 2 indicates a soundproof engine-driven working machine equipped with the exhaust structure of the present invention.

[0035] This soundproof engine-driven work machine 1 is packaged by housing component equipment such as the engine 51 and the work machine body (not shown) within a soundproof box 10, thereby reducing the leakage of noise generated within the soundproof box 10 and making it easy to transport and install.

[0036] The aforementioned soundproof box 10 which houses the components of the soundproof engine-driven work machine 1 is composed of a base 20 which is rectangular in plan view on which the engine 51, the work machine body and other components are placed, and a soundproof case 30 which covers the base 20 when the components are placed on it.

[0037] Of these, the soundproof case 30 is a box-shaped case consisting of a front panel 31, a rear panel 32, a side panel 33, and a top panel 34, and by placing this soundproof case 30 on the base 20, a storage space is formed within the soundproof case 30 to accommodate the component equipment placed on the base 20.

[0038] In the soundproof case 30 in Figures 1 and 2, a portion of the side panel 33 on the front side of the page is removed.

[0039] The space within this soundproof case 30 is divided into two chambers, front and rear, in the longitudinal direction of the soundproof box 10, by a partition wall 12 erected vertically from the base 20, with an engine chamber 30a, in which the engine 51, the working machine body, etc. are housed, formed on the front panel 31 side, and an exhaust chamber 30b formed on the rear panel 32 side.

[0040] The aforementioned engine compartment 30a and exhaust chamber 30b are connected through a communication port (not shown) provided in the central part of the partition wall 12, and the exhaust chamber 30b is connected to the outside of the aircraft through an exhaust port 35 provided in the top cover 34 as shown in Figures 1 and 2.

[0041] A radiator 54 for the engine 51, consisting of an upper tank 54a, a lower tank 54c, and a core 54b, is arranged in the portion where a communication port (not shown) is formed in the partition wall 12 that divides the space within the soundproof case 30, as shown in Figure 3.

[0042] The positioning of the radiator 54 relative to the partition wall 12 may be such that the radiator 54 is attached within the aforementioned communication opening provided in the partition wall 12, or the radiator 54 may be attached to the engine chamber 30a side or the exhaust chamber 30b side of the partition wall 12 so that the core 54b of the radiator 54 faces the communication opening formed in the partition wall 12, and the configuration is not particularly limited as long as it is configured so that the cooling air generated by the cooling fan 55 described later can pass through the communication opening in the partition wall 12 and the core 54b of the radiator 54 and flow from the engine chamber 30a to the exhaust chamber 30b.

[0043] As shown in Figures 1 and 2, a cooling fan 55 is disposed within the engine compartment 30a of the soundproof box 10 to generate cooling air directed toward the radiator 54 mentioned above. When the cooling fan 55 is operated to generate cooling air, the air within the engine compartment 30a passes through the core 54b of the radiator 54 and undergoes heat exchange, and is then introduced into the exhaust chamber 30b and exhausted outside the aircraft through the exhaust port 35.

[0044] In this way, in the soundproof engine-driven work machine 1 having the above-mentioned structure, an exhaust section 40 is formed from the exhaust chamber 30b to the exhaust port 35 for discharging the cooling air outside the machine after it has passed through the radiator 54 and been heat exchanged.

[0045] [Upper and lower baffles] Within the exhaust chamber 30b of the soundproof box 10 configured as described above, an upper baffle plate 61, and preferably a lower baffle plate 62 (621, 622) together with the upper baffle plate 61, is provided horizontally from the surface of the radiator 54 facing the exhaust chamber 30b toward the rear panel 32 of the soundproof case 30.

[0046] The upper baffle plate 61 and the lower baffle plate 62 (621, 622) are both formed in a rectangular shape in a plan view with a length L (see Figure 5) that approximately corresponds to the spacing between the inner walls of the side panels 33, so that they can be installed within the exhaust chamber 30b so as to bridge the inner walls of the side panels 33, 33 of the soundproof case 30.

[0047] Of these, the upper baffle plate 61 is mounted horizontally within the exhaust chamber 30b with one side 61a forming one end in the width direction at a height position equal to or higher than the upper end position T (see Figure 3) of the core 54b of the radiator 54, and in the illustrated embodiment at the same height position as the upper end position T of the core 54b of the radiator 54, in contact with or close to the side of the exhaust chamber side of the radiator 54 (close to it in the illustrated embodiment), so that the spacing W1 between the one side 61a and the other side 61b is set so that the other side 61b opposite to the one side 61a extends to a position where it partially overlaps with the exhaust port 35 in a planar view.

[0048] In addition, the lower baffle plate 62 (621, 622) is mounted horizontally within the exhaust chamber 30b with one side 621a, 622a forming one end of its width direction being in contact with or close to (close to in the illustrated embodiment) the side of the core 54b of the radiator 54 facing the exhaust chamber 30b, below the upper baffle plate 61 and at a height position above the height center position M of the core 54b of the radiator 54.

[0049] The distances W2a, W2b between the sides 621a, 622a of this lower baffle plate 62 (621, 622) and the other sides 621b, 622b facing the sides 621a, 622a are formed shorter than the distance W1 between the side 61a and the other side 61b of the upper baffle plate 61 described above (see Figure 4).

[0050] In the illustrated embodiment, a plurality of lower baffle plates 62 (621, 622) (two in the illustrated embodiment) are provided, and these lower baffle plates 62 (621, 622) are attached at intervals in the height direction.

[0051] When multiple lower baffles 621, 622 are provided in this manner, the spacing W2b between one side 622a and the other side 622b of the lower baffle plate 622 arranged below is made shorter than the spacing W2a between one side 621a and the other side 621b of the upper lower baffle plate 621.

[0052] In this way, when the spacing W2a, W2b between one side 621a, 622a and the other side 621b, 622b of the lower baffle plate 62 (621, 622) is formed so that the spacing W2a, W2b between the sides 621a, 622a and the other sides 621b, 622b of the lower baffle plates 621, 622 is shorter the lower the side that is positioned, the other side 61b of the upper baffle plate 61 and the other sides 621b, 622b of the lower baffle plates 621, 622 may all be configured to be arranged on the same straight line in side view, as shown by the dotted line in Figure 3.

[0053] Of the sides of the upper baffle plate 61 and the lower baffle plate 62 (621, 622), the side 61a, 621a, 622a that is in contact with or positioned close to the radiator 54 is provided with an upwardly protruding flange 63, which prevents rainwater that falls into the exhaust chamber 30b through the exhaust port 35 from falling onto the upper surface of the upper baffle plate 61 or the lower baffle plate 62 (621, 622) from falling onto the radiator 54 side, thereby preventing such rainwater from passing through the core 54b of the radiator 54 and entering the engine compartment 30a side.

[0054] In addition, among each side of the upper baffle plate 61 and the lower baffle plate 62 (621, 622), the other side 61b, 621b, 622b opposite the side 61a, 621a, 622a is provided with a downwardly protruding flange 64, which reinforces the upper baffle plate 61 and the lower baffle plate 62 (621, 622) and is configured so that rainwater that falls on the upper baffle plate 61 and the lower baffle plate 62 (621, 622) can fall downward from the other side 61b, 621b, 622b without accumulating.

[0055] It is preferable to attach a known sound insulating material such as urethane foam to the upper baffle plate 61 and the lower baffle plate 62 (621, 622) configured in this manner.

[0056] The upper baffle plate 61 and the lower baffle plate 62 (621, 622) configured as described above may be attached independently and separately so as to bridge the inner surfaces of the side panels 33 of the soundproof case 30, but in this embodiment, the above-mentioned upper baffle plate 61 and the lower baffle plate 62 (621, 622) are installed between two side panels 65, 65, and a baffle plate unit 70 is formed in advance by connecting the upper baffle plate 61 and the upper lower baffle plate 621, and the upper lower baffle plate 621 and the lower lower baffle plate 622 with a partition plate 66.By installing this baffle plate unit 70 in the exhaust chamber 30b, the upper baffle plate 61 and the lower baffle plate 62 (621, 622) can be installed in the exhaust chamber 30b so as to be in a positional relationship with the above-mentioned radiator 54, thereby improving workability during assembly.

[0057] [Effect, etc.] (1) Noise reduction In a soundproof engine-driven work machine 1 equipped with an exhaust section 40 configured as described above, noise generated within the engine compartment 30a reaches the exhaust chamber 30b through the communication opening in the partition wall 12 and the gaps between the fins on the core 54b of the radiator 54, and leaks outside the machine through the exhaust port 35.

[0058] Here, if we assume that the position indicated by the symbol NS in Figure 6 (A) is the noise source within the engine compartment 30a, the path along which the straight-line sound from this noise source NS can pass through the core 54b of the radiator 54 and directly reach the exhaust port 35 is the range between the line ND1 connecting the noise source NS and the upper end T of the core of the radiator 54, and the line ND2 connecting the noise source NS and the edge 35b of the exhaust port 35 near the rear panel 32.

[0059] However, the gap between the lines ND1 and ND2 is blocked by an upper baffle plate 61 and a lower baffle plate 62 (621, 622) as shown in FIG. 6(A).

[0060] Furthermore, even if it is assumed that the noise source NS shown in Figure 6 (A) is moved up and down, the upper baffle plate 61 and the lower baffle plate 62 (621, 622) are positioned to block the path of the straight-line sound from the noise source NS, and therefore, by providing the upper baffle plate 61 and the lower baffle plate 62 (621, 622), all or part of the straight-line sound from the noise source NS cannot reach the exhaust port 35 without colliding with the upper baffle plate 61 or the lower baffle plate 62 (621, 622).

[0061] In addition, the path along which noise that has passed through the core 54b of the radiator 54, including not only straight-line sound from the noise source NS but also reflected sound within the engine compartment 30a, can directly reach the exhaust port 35 is the range between line NL1 connecting the edge 35a of the exhaust port on the radiator 54 side and the upper end position T of the core 54b of the radiator 54, and line NL2 connecting the edge 35b of the exhaust port 35 on the rear panel 32 side and the lower end position B of the core 54b of the radiator 54, as shown in Figure 6 (B).

[0062] However, as is clear from Figure 6(B), part of the gap between lines NL1 and NL2 is also blocked by upper baffle plate 61 and lower baffle plate 62 (621, 622), so that of the noise that passes through radiator 54, only that part that travels through the range indicated by the dashed diagonal line in Figure 6(B), i.e., only a portion of the reflected sound generated in the engine compartment 30a, can reach the exhaust outlet 35 directly.

[0063] As a result, in the soundproof engine-driven work machine 1 equipped with the exhaust structure of the present invention, the noise leaking outside the machine can be significantly reduced, and in particular, by attaching a soundproofing material such as urethane foam to the upper baffle plate 61 and the lower baffle plate 62 (621, 622), it is possible to more effectively reduce the leakage of noise.

[0064] As an example, in the soundproof engine-driven work machine 1 having the configuration shown in Figures 1 and 2, the sound power level (Lw) when the upper baffle plate 61 and the lower baffle plate 62 (621, 622) were not provided was 103 dB. However, when a baffle plate unit 70 (having a structure in which foamed urethane is attached as sound insulation material to the upper baffle plate 61 and the lower baffle plate 621, 622, respectively) having the configuration shown in Figures 3 to 5 was installed, the sound power level (Lw) could be reduced by -1 dB to 102 dB.

[0065] (2) Maintaining or improving cooling performance As explained as the prior art, a configuration in which ducts or louvers are provided at the opening of a soundproof box reduces the amount of cooling air flowing in exchange for reducing the amount of noise leaking outside the machine. However, in the soundproof engine-driven work machine 1 equipped with the exhaust structure of the present invention, while achieving the effect of reducing noise as described above, noise can be reduced without reducing the heat exchange efficiency of the radiator 54, and therefore without reducing the cooling performance of the soundproof engine-driven work machine.

[0066] In particular, in the configuration of the embodiment described with reference to Figures 1 to 5, the cooling performance has been improved compared to the soundproof engine-driven working machine 1 before the upper baffle plate 61 and the lower baffle plate 62 (621, 622) were provided.

[0067] The reasons why such an improvement in cooling performance is achieved are not entirely clear, but it is presumed that the improvement in cooling performance is achieved for the following reasons.

[0068] - Uniform flow rate of cooling air In a configuration in which the exhaust port 35 is provided on the top panel 34 of the exhaust chamber 30b, the upper side of the radiator 54 is located closer to the exhaust port 35 than the lower side.

[0069] Therefore, as shown in Figure 7 (A), in a configuration that does not have upper baffle plate 61 and lower baffle plate 62 (621, 622), when the cooling air that passes through the upper side of core 54b of radiator 54, which is close to the exhaust port 35, forms a flow toward the exhaust port 35, the cooling air that passes through the lower side of core 54b of radiator 54 is blocked by the flow on the upper side.

[0070] Therefore, in a configuration that does not have the upper baffle plate 61 or the lower baffle plate 62 (621, 622), the wind speed (air volume) of the cooling air flowing through the lower side of the core 54b of the radiator 54 decreases, and it is thought that the lower side of the radiator 54 is not able to contribute sufficiently to heat exchange.

[0071] In contrast, in the configuration of the present invention, the cooling air passing above the core 54b of the radiator 54 encounters resistance as it passes through the gaps between the upper baffle plate 61 and the upper lower baffle plate 621, and between the upper lower baffle plate 621 and the lower lower baffle plate 622, and thereby its flow speed decreases, thereby making it possible to make the flow speed of the cooling air passing above the core 54b of the radiator 54 closer to the flow speed of the cooling air passing below.

[0072] Moreover, since the widths W1, W2a, W2b of the upper baffle plate 61 and the lower baffle plate 62 (621, 622) become narrower as they go downward, the cooling air passing through the upper side of the core 54b of the radiator 54 encounters greater resistance, while the resistance encountered by the cooling air decreases as it goes downward (towards the central position M).

[0073] As a result, regardless of the position in the height direction of the radiator 54 through which it passes, the wind speed of the cooling air, and therefore the volume of the cooling air passing through the radiator 54, is made uniform, and heat exchange is carried out evenly throughout the entire height direction of the radiator 54. This improves the heat exchange efficiency of the radiator 54, and is presumably improving the cooling performance of the soundproof engine-driven work machine.

[0074] Rectification effect In addition, the upper baffle plate 61 and the lower baffle plate 62 (621, 622) provided in the exhaust air chamber 30b function as rectifying plates for the cooling air that has passed through the core 54b of the radiator 54, and the intervals W2a, W2b between the sides 621a, 622a and the other sides 621b, 622b of the lower baffle plate 62 (621, 622) are shorter than the interval W1 between the side 61a and the other side 61b of the upper baffle plate 61. By making the spacing W2b between one side 622a and the other side 622b of the lower baffle plate 622 shorter than the spacing W2a between one side 621a and the other side 621b of the plate 621, as shown in Figure 7 (B), the cooling air that passes through the lower side of the core 54b of the radiator 54 can flow toward the exhaust port 35 without being obstructed by the upper baffle plate 61 or the lower baffle plate 62 (621, 622).

[0075] In this way, the cooling air that has passed through the core 54b of the radiator 54 can be allowed to reach the exhaust port 35 smoothly, thereby increasing the amount of cooling air passing through the radiator 54, thereby improving the heat exchange efficiency of the radiator 54, which is also thought to be one of the reasons why the cooling performance has been improved.

[0076] (3) Preventing rainwater from entering In addition, as described above, in the soundproof engine-driven work machine 1 equipped with the exhaust section structure of the present invention, not only is it possible to simultaneously maintain or improve cooling performance and reduce noise, but it is also possible to effectively prevent rainwater that has entered the exhaust chamber 30b through the exhaust port 35 from passing through the core 54b of the radiator 54 and entering the engine chamber 30a.

[0077] That is, as shown in Figure 8, even if rainwater enters the exhaust chamber 30b through the exhaust port 35 as indicated by the dashed arrow, this rainwater collides with the upper surfaces of the upper baffle plate 61 and the lower baffle plate 62 (621, 622) and is therefore unable to directly reach the core 54b of the radiator 54.

[0078] In this way, when the upper baffle plate 61 and the lower baffle plate 62 (621, 622) are given the function of preventing rainwater from entering, a flange 63 (see Figure 4) protruding upward is provided on one side 61a, 621a, 622a of the four sides of the upper baffle plate 61 and the lower baffle plate 62 (621, 622) that is positioned on the radiator 54 side, so that rainwater that falls on the top surface of the upper baffle plate 61 or the lower baffle plate 62 (621, 622) does not flow down toward the radiator 54 side.

[0079] In this case, in order to prevent rainwater falling onto the upper baffle plate 61 and the lower baffle plate 62 (621, 622) from accumulating on the upper surface of the upper baffle plate 61 and the lower baffle plate 62 (621, 622), a flange 64 protruding downward may be provided on the other sides 61b, 621b, 622b opposite the one sides 61a, 621a, 622a, so that rainwater can fall from the other sides 61b, 621b, 622b.

[0080] Furthermore, by forming such flanges 63, 64, the strength of the upper baffle plate 61 and the lower baffle plate 62 (621, 622) can also be improved.

[0081] In this way, in the soundproof engine-driven work machine 1 of the present invention, by making a relatively simple structural modification by providing an upper baffle 61 and a lower baffle 62 (621, 622) in the exhaust chamber 30b, it is possible to obtain the combined effects of reducing noise, maintaining or improving cooling performance, and preventing rainwater that has entered through the exhaust port 35 from entering the engine chamber 30a through the core 54b of the radiator 54. [Explanation of symbols]

[0082] 1. Soundproof engine-driven work equipment 10 Soundproof box 12 Partition Wall 20 Foundations 30 Soundproof Case 30a Engine room 30b Ventilation room 31 Front Panel 32 Rear panel 33 Side Panel 34 Top Panel 35 Ventilation port 35a, 35b Edge (of exhaust port 35) 40 Air exhaust section 51 Engine 54 Radiator 54a Upper Tank 54b Core 54c Lower Tank 55 Cooling Fan 61 Upper baffle plate 61a Side (of upper baffle plate) 61b Other side (of upper baffle plate) 62 Lower baffle plate 621 Lower baffle plate (upper side) 621a One side (of the lower baffle plate 621) 621b Other side (of lower baffle plate 621) 622 Lower baffle plate (lower side) 622a One side (of the lower baffle plate 622) 622b other side (of lower baffle plate 622) 63 Flange (upward) 64 Flange (downward) 65 Side Panel 66 Partition 70 Baffle Plate Unit 300 Soundproof engine-driven work machine 310 Soundproof Box 312 Partition Wall 320 Foundations 327 Air Intake 330 Soundproof Case 330a Engine Room 330b Ventilation room 332 Rear Panel 333 Side Panel 334 Top Panel 335 Exhaust port 351 Engine 352 Work machine body 354 Radiator 355 Cooling Fan 360 Duct 361 Louver T Top end position of radiator core M Height center position of radiator core B. Bottom end position of radiator core W1: Distance between one side 61a and the other side 61b of the upper baffle plate 61 W2a: Distance between one side 621a and the other side 621b of the lower baffle plate 621 W2b: Distance between one side 622a and the other side 622b of the lower baffle plate 622 L Length of upper and lower baffles NS Noise source ND1: A line connecting the noise source NS and the top end T of the radiator core ND2: A line connecting the noise source NS and the edge 35b of the exhaust port 35 NL1: A line connecting the upper end T of the radiator core and the edge 35a of the exhaust port 35 NL2: A line connecting the lower end B of the radiator core and the edge 35b of the exhaust port 35

Claims

1. A soundproof engine-driven working machine in which the inside of a soundproof box is divided into two compartments by a vertically erected partition wall, one compartment being an engine compartment in which an engine and a working machine body are housed, and the other compartment being an exhaust compartment communicating with the engine compartment via a communication port provided in the partition wall, an exhaust port communicating with the outside of the machine is provided in a top panel at the position where the exhaust compartment is formed, a cooling fan is provided for generating cooling air from the engine compartment to the exhaust compartment, and a radiator for the engine is disposed at the position where the communication port provided in the partition wall is formed, and an exhaust section is formed in a section from the exhaust compartment to the exhaust port to discharge the cooling air after heat exchange in the radiator to the outside of the machine, An upper baffle plate having a rectangular shape in plan view is arranged horizontally in the exhaust chamber, with one side of the baffle plate being in contact with or close to the side surface of the radiator on the exhaust chamber side at a height position equal to or higher than the upper end position of the radiator core, and the other side opposite to the one side being extended to a position partially overlapping with the exhaust port in a plan view, A lower baffle plate having a rectangular shape in a plan view and one side of which is in contact with or close to a side surface of the core of the radiator on the side of the exhaust chamber at a height position above the center position of the core in the height direction of the radiator, is disposed horizontally in the exhaust chamber, An exhaust structure for a soundproof engine-driven working machine, characterized in that the distance between the one side of the lower baffle plate and the other side opposite to the one side is formed shorter than the distance between the one side of the upper baffle plate and the other side.

2. 2. The exhaust structure of a soundproof engine-driven working machine as claimed in claim 1, characterized in that a plurality of lower baffle plates are provided, arranged at intervals above and below, and the interval between the one side and the other side of the lower baffle plate is made shorter the lower the lower the baffle plate is arranged.

3. 3. The exhaust structure of a soundproof engine-driven working machine according to claim 2, wherein a sound-proofing material is attached to the upper baffle plate and / or the lower baffle plate.

4. 4. The exhaust structure of a soundproof engine-driven working machine according to claim 2, wherein an upwardly projecting flange is provided on said one side of said upper baffle plate and said lower baffle plate.

5. 5. The exhaust structure of a soundproof engine-driven working machine according to claim 2, wherein the other sides of the upper baffle plate and the lower baffle plate are provided with downwardly projecting flanges.

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