Work machine

Abstract

To provide a work machine capable of reducing noise due to engine sound leaked from an exhaust port formed in a top wall to the outside toward a side part.SOLUTION: A work machine 1 includes: an outer wall 13 surrounding a machine room 80; and an engine 30 arranged in the machine room 80. The outer wall 13 includes a top wall 15. The top wall 15 includes: a high wall 16R; a low wall 17 located at a position lower than the high wall 16R; and an adjacent wall 18R located at a position adjacent to the low wall 17 and extending from the high wall 16 downward or diagonally downward. In the low wall 17, an exhaust port 77 for exhausting air in the machine room 80 to the outside of the machine room 80 is formed.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to work machines such as hydraulic excavators. [Background technology]

[0002] In general, a work machine includes an exterior wall surrounding a machine room and an engine disposed in the machine room. An exhaust port is formed in the exterior wall for discharging air from the machine room to the outside of the machine room, and engine noise generated by the engine leaks from the exhaust port to the outside of the machine room, causing noise. Therefore, it is desirable to reduce noise caused by the engine noise.

[0003] Patent Document 1 discloses a work machine in which a first exhaust port that discharges air in the axial direction of an engine output shaft and a second exhaust port that discharges air upward are provided close to each other. The first exhaust port is formed in the bonnet (top wall) so as to open in the axial direction of the engine output shaft (horizontally). This work machine is equipped with an exhaust guide that changes the flow direction of air discharged from the first exhaust port in the axial direction of the engine output shaft to upward on the windward side of the second exhaust port. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2011-208632 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the work machine described in Patent Document 1, it is desirable to further reduce noise caused by engine sound that leaks to the outside from the first exhaust port and travels sideways.

[0006] An object of the present disclosure is to provide a work machine capable of reducing noise caused by engine noise leaking to the outside and traveling sideways from an exhaust port formed in a top wall. [Means for solving the problem]

[0007] A working machine according to a first aspect comprises an outer wall surrounding a machine room and an engine disposed in the machine room, the outer wall including a top wall, the top wall including a high wall, a low wall positioned lower than the high wall, and an adjacent wall positioned adjacent to the low wall and extending downward or diagonally downward from the high wall, and the low wall is formed with an exhaust port for discharging air from the machine room to the outside of the machine room.

[0008] In this work machine, the adjacent wall extends downward or diagonally downward from the high wall and is located adjacent to the low wall, and an exhaust port is formed in this low wall. That is, the adjacent wall has a portion that extends from a position adjacent to the low wall where the exhaust port is formed to a high wall that is located higher than the low wall. Therefore, a portion of the engine sound that leaks to the outside from the exhaust port is prevented from traveling laterally by the adjacent wall. This makes it possible to reduce the loudness (volume) of the engine sound that leaks to the outside from the exhaust port and is transmitted to the side of the work machine. Therefore, in this work machine, it is possible to reduce noise caused by engine sound that leaks to the outside from an exhaust port formed in the top wall and travels laterally.

[0009] The second aspect preferably includes the following configuration in addition to the first aspect. That is, the working machine according to the second aspect preferably further includes a shielding wall disposed in the machine room below the bottom wall and above the engine, and the shielding wall is disposed in a position so as to cover the exhaust port from below. In this second aspect, the shielding wall can prevent foreign matter such as rainwater and dust from entering the machine room through the exhaust port.

[0010] The third aspect preferably includes the following configuration in addition to the second aspect. That is, in the work machine according to the third aspect, it is preferable that the adjacent wall extends from the high wall to the shielding wall. In this third aspect, the adjacent wall and the shielding wall are arranged so as to be continuous, so that foreign matter such as rainwater and dust is more effectively prevented from entering the machine room through the exhaust port.

[0011] The fourth aspect is preferably the second or third aspect further provided with the following configuration. That is, in the working machine according to the fourth aspect, it is preferable that the low wall and the shielding wall define a passage for guiding the air in the machine room laterally to the exhaust port, and the adjacent wall is configured to guide the air guided to the exhaust port upward to the height position of the high wall. In this fourth aspect, the air in the machine room is smoothly guided laterally along the passage to the exhaust port, and the air guided to the exhaust port is smoothly guided upward along the adjacent wall to the height position of the high wall. In addition, a part of the engine sound traveling laterally along the passage hits the adjacent wall before reaching the exhaust port, and is prevented from traveling laterally by this adjacent wall. This makes it possible to further effectively reduce noise caused by the engine sound leaking to the outside from the exhaust port formed in the top wall and traveling laterally.

[0012] A fifth aspect may further include the following configuration in any of the first to fourth aspects. That is, in the work machine according to the fifth aspect, the exhaust port may be defined by a side edge of the low wall and the adjacent wall. In this fifth aspect, since the adjacent wall is located directly beside the exhaust port, the adjacent wall can more effectively prevent a portion of the engine sound leaking to the outside from the exhaust port from traveling sideways.

[0013] The sixth aspect is preferably any one of the first to fifth aspects further including the following configuration. That is, in the work machine according to the sixth aspect, it is preferable that the high wall is a right side high wall located to the right of the low wall, the adjacent wall is a right side adjacent wall located to the right of the low wall and extending downward or diagonally downward from the right side high wall, and the top wall further includes a left side high wall located to the left of the low wall and a left side adjacent wall located to the left of the low wall and extending downward or diagonally downward from the left side high wall. In this sixth aspect, the right side adjacent wall and the left side adjacent wall are respectively located to the right and left of the low wall, and an exhaust port is formed in this low wall, so that a part of the engine sound leaking to the outside from the exhaust port is prevented from traveling to the right by the right side adjacent wall, and another part of the engine sound leaking to the outside from the exhaust port is prevented from traveling to the left by the left side adjacent wall. This makes it possible to reduce the volume (sound volume) of the engine sound leaking to the outside from the exhaust port and transmitted to the right and left of the work machine, respectively. Therefore, with this work machine, noise caused by engine sound leaking to the outside through the exhaust port formed in the top wall and traveling sideways can be further reduced.

[0014] A seventh aspect may further include the following configuration in any of the first to fifth aspects: That is, in the work machine according to the seventh aspect, the high wall may be located to the right, left, front or rear of the low wall. Effect of the Invention

[0015] According to the present disclosure, a work machine is provided that is capable of reducing noise caused by engine noise that leaks outside and travels sideways through an exhaust port formed in a top wall. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 is a left side view showing an example of a work machine according to an embodiment. [Diagram 2] FIG. 2 is a perspective view of an upper rotating body of the work machine as viewed diagonally from the rear left. [Diagram 3] FIG. [Figure 4] FIG. 2 is a cross-sectional view taken along line AA in FIG. [Diagram 5] FIG. 2 is a right side view showing the rear of the work machine. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] An embodiment of the present disclosure will be described with reference to the drawings.

[0018] As shown in Fig. 1, the work machine 1 includes a lower travelling body 2 including a travelling device, an upper rotating body 3 supported on the lower travelling body 2 so as to be rotatable relative to the lower travelling body 2 about a vertically extending rotating shaft, and a working device 4 supported on the upper rotating body 3. The work machine 1 according to this embodiment is a hydraulic excavator, but the work machine in this disclosure is not limited to hydraulic excavators and may be other work machines such as a crane or a bulldozer. The travelling device may be a crawler travelling device 2a shown in Fig. 1, or a travelling device having tires (not shown).

[0019] The working device 4 includes a boom 6 that is attached to the upper rotating body 3 so as to be able to rise and fall, an arm 7 that is attached to the boom 6 so as to be able to rotate, and a tip attachment 8 that is attached to the arm 7 so as to be able to rotate. In this embodiment, the tip attachment 8 is a bucket, but the tip attachment may be another tip attachment such as a grapple, a fork, a crusher, or the like.

[0020] The upper rotating body 3 includes a rotating frame 3a, a cab 12 supported by the rotating frame 3a, and an outer wall 13 disposed behind the cab 12. The outer wall 13 has, for example, a box shape and defines a machine room 80. The machine room 80 will be described later. As shown in Figs. 2 and 3, the cab 12 is disposed, for example, at the left front part of the rotating frame 3a. A driver's seat, operating levers, operating pedals, etc. are disposed in the cab 12. A counterweight 22 is disposed at the rear of the upper rotating body 3. The counterweight 22 is a weight for balancing.

[0021] The work machine 1 includes a hydraulic pump 98, which will be described later, and a plurality of actuators. Each of the plurality of actuators operates by receiving a supply of hydraulic oil discharged from the hydraulic pump 98. The plurality of actuators include a boom cylinder 9 for raising and lowering the boom 6, an arm cylinder 10 for rotating the arm 7, a tip attachment cylinder 11 for rotating the tip attachment 8, and a hydraulic motor (not shown) for rotating the upper rotating body 3 relative to the lower traveling body 2.

[0022] The upper rotating body 3 of the work machine 1 has a machine room 80 surrounded by an outer wall 13. In the specific example shown in Figures 2 and 3, the machine room 80 is formed rearward of the cab 12, but for example, it may be formed on the side (right side) of the cab 12, or it may be formed both rearward and sideward of the cab 12. As shown in Figures 1 to 3, the outer wall 13 includes a side wall 14 arranged so as to cover the machine room 80 from the side, and a top wall 15 arranged so as to cover the machine room 80 from above.

[0023] The outer wall 13 of the upper rotating body 3 has an intake port 71 and a top wall exhaust port 77. The top wall exhaust port 77 is an example of an exhaust port in the present disclosure. The intake port 71 is an opening for drawing air outside the machine room 80 (outside air) into the machine room 80 as cooling air. The top wall exhaust port 77 is an opening for discharging air in the machine room 80 to the outside of the machine room 80. The top wall exhaust port 77 is formed in the top wall 15. In this embodiment, the intake port 71 is formed in the left rear part of the upper rotating body 3, but the location where the intake port 71 is formed is not limited to the left rear part of the upper rotating body 3.

[0024] The outer wall 13 may further have a first sidewall exhaust port 75 and a second sidewall exhaust port 76. Each of the first sidewall exhaust port 75 and the second sidewall exhaust port 76 is an opening for discharging air in the machine room 80 to the outside of the machine room 80. In this embodiment, the first sidewall exhaust port 75 and the second sidewall exhaust port 76 are formed in the right rear part of the upper rotating body 3 (specifically, the right rear part of the sidewall 14), but the location where the first sidewall exhaust port 75 and the second sidewall exhaust port 76 are formed is not limited to the right rear part of the upper rotating body 3.

[0025] As shown in Fig. 4, the machine chamber 80 includes an intake chamber 81 and an engine chamber 82. In this embodiment, the top wall exhaust port 77 is formed in a portion of the top wall 15 that covers the engine chamber 82 from above. The intake port 71, the intake chamber 81, and the engine chamber 82 are arranged to be aligned in this order in the left-right direction as shown in Fig. 4. Air in the engine chamber 82 is exhausted to the outside of the machine chamber 80 through the top wall exhaust port 77, the first side wall exhaust port 75, and the second side wall exhaust port 76.

[0026] As shown in FIG. 4, the working machine 1 includes a cooling fan 20, an engine 30, a heat exchanger 40, an intake guide 50, and a hydraulic pump 98. The cooling fan 20 generates an air flow AF that flows through the intake port 71, the intake chamber 81, the engine chamber 82, and the top wall exhaust port 77 (side wall exhaust ports 75, 76) in this order. The intake guide 50 is disposed in the intake chamber 81. The heat exchanger 40 is interposed between the intake chamber 81 and the engine chamber 82. The intake guide 50 guides the air that flows from the intake port 71 into the intake chamber 81 to the heat exchanger 40. The cooling fan 20, the engine 30, and the hydraulic pump 98 are disposed in the engine chamber 82. The engine 30 drives the hydraulic pump 98.

[0027] As shown in Fig. 4, the intake guide 50 includes an intake port side upper wall 51, an intake port side lower wall 54, and a duct 55 (heat exchanger side duct). The intake port side upper wall 51 and the intake port side lower wall 54 guide air flowing from the intake port 71 into the intake chamber 81 to the duct 55. The duct 55 further guides the guided air to the heat exchanger 40. A filter 85 is disposed in the duct 55. The intake port side upper wall 51 is disposed at the upper part of the intake chamber 81, and the intake port side lower wall 54 is disposed at the lower part of the intake chamber 81.

[0028] 4, the airflow AF flowing from the intake port 71 into the intake chamber 81 is guided by the intake guide 50 so that it flows in a roughly Z-shape (or S-shape) into the heat exchanger 40. By forming such a Z-shaped passage, noise caused by engine sound that passes through the heat exchanger 40 and leaks to the outside from the intake port 71 is effectively reduced.

[0029] The work machine 1 further includes a partition 90 that separates the intake chamber 81 and the engine room 82. In this case, the intake chamber 81 and the engine room 82 are separated by the partition 90, so that engine noise passing through areas other than the heat exchanger 40 and heading toward the intake port 71 can be reduced. In this embodiment, as shown in Fig. 4, the partition 90 includes an upper partition 90A that closes the gap between the heat exchanger 40 and the top wall 15 of the outer wall 13, and a lower partition 90B that closes the gap between the heat exchanger 40 and the floor surface (for example, the upper surface of the revolving frame 3a). The partition 90 may further include a side partition (not shown) that closes the gap between the heat exchanger 40 and the side wall 14 of the outer wall 13.

[0030] 3, the right rear and left rear parts of the upper rotating body 3 have a curved shape when viewed from above, with a portion of the air intake port 71 formed in the left rear part and the other portion of the air intake port 71 formed in the left side part (left side part of the upper rotating body 3) extending in the front-rear direction. Since a portion of the air intake port 71 is formed in the curved left rear part, it becomes easier to ensure the opening area of ​​the air intake port 71.

[0031] 4, an air cleaner 95 is disposed in the intake chamber 81. The air cleaner 95 purifies the air in the intake chamber 81, and then supplies the purified air to the engine 30 through unillustrated piping.

[0032] The work machine 1 includes a hydraulic pump 98 driven by the engine 30, and a plurality of mufflers 97 disposed on the hydraulic pump 98 and configured to reduce the exhaust noise of the engine 30. The hydraulic pump 98 and the plurality of mufflers 97 are disposed in the engine compartment 82.

[0033] The work machine 1 includes a first partition 61 disposed in the machinery room 80. In this embodiment, the first partition 61 is disposed in the engine room 82 of the machinery room 80. The first partition 61 has a vertical wall portion 64 interposed between the engine 30 and the first sidewall exhaust port 75 and extending upward, and a horizontal wall portion 65 extending laterally from an upper portion of the vertical wall portion 64 toward the first sidewall exhaust port 75.

[0034] In this work machine 1, the first partition 61 having the vertical wall portion 64 interposed between the engine 30 and the first sidewall exhaust port 75 and the horizontal wall portion 65 extending laterally from an upper portion of the vertical wall portion 64 toward the first sidewall exhaust port 75 is disposed in the engine chamber 82 of the machinery room 80, so that engine noise leaking to the outside from the first sidewall exhaust port 75 is reduced, and air is smoothly guided toward the first sidewall exhaust port 75 in the engine chamber 82 of the machinery room 80. That is, this work machine 1 can reduce the noise of the engine 30 and improve the air flow in the engine chamber 82 of the machinery room 80. Therefore, the work machine 1 can improve the air flow in the engine chamber 82 of the machinery room 80 while reducing noise caused by engine noise leaking to the outside from the first sidewall exhaust port 75.

[0035] In the specific example shown in Fig. 4, the first partition 61 has a substantially L-shape when the work machine 1 is viewed from behind (i.e., in a rear view). The vertical wall portion 64 is disposed so as to extend in the vertical direction, and the horizontal wall portion 65 is disposed so as to extend in the horizontal direction, but the extending directions of the vertical wall portion 64 and the horizontal wall portion 65 are not limited to the specific example shown in Fig. 4. For example, the "upward" direction in which the vertical wall portion 64 extends may be a direction parallel to the vertical direction, or a direction inclined relative to the vertical direction. The "lateral direction" in which the horizontal wall portion 65 extends may be a direction parallel to the horizontal direction, or a direction inclined relative to the horizontal direction.

[0036] In the specific example shown in Fig. 4, each of the vertical wall portion 64 and the horizontal wall portion 65 has a flat plate-like shape, but the shapes of the vertical wall portion 64 and the horizontal wall portion 65 are not limited to the specific example shown in Fig. 4. For example, the vertical wall portion 64 may have a curved shape, or may have a shape including a flat plate-like portion and a curved portion. Similarly, the horizontal wall portion 65 may have a curved shape, or may have a shape including a flat plate-like portion and a curved portion.

[0037] The vertical wall portion 64 is disposed at a position such that the vertical wall portion 64 blocks part or all of the engine sound generated by the engine 30 and traveling straight toward the first sidewall exhaust port 75. The vertical wall portion 64 is disposed at a position such that the vertical wall portion 64 covers part or all of the engine 30 when the engine 30 is viewed from the first sidewall exhaust port 75.

[0038] 4, the range indicated by the arrows between straight lines L1 and L2 indicates the range of sound (direct sound) that is transmitted in a linear manner from the engine 30 and muffler 97 to the first sidewall exhaust port 75, among the sound that leaks from the first sidewall exhaust port 75 to the outside of the machine room 80. The straight line L1 is a straight line that passes through the upper end 75A of the first sidewall exhaust port 75 and touches the first partition 61 when the work machine 1 is viewed from behind, and indicates the upper limit of the direct sound. The straight line L2 is a straight line that passes through the lower end 75B of the first sidewall exhaust port 75 and touches the muffler 97 when the work machine 1 is viewed from behind, and indicates the lower limit of the direct sound.

[0039] In the specific example shown in FIG. 4, since the upper end of the muffler 97 is located above the upper end 61A of the first partition 61 and the upper end 30A of the engine 30, the straight line L2 indicating the lower limit of the direct sound is a straight line that passes through the lower end 75B of the first sidewall exhaust port 75 and is tangent to the muffler 97. For example, when the upper end 30A of the engine 30 is located above the upper end of the muffler 97 and the upper end 61A of the first partition 61, the straight line L2 indicating the lower limit of the direct sound may be a straight line that passes through the lower end 75B of the first sidewall exhaust port 75 and is tangent to the engine 30. Also, for example, when the upper end 61A of the first partition 61 is located above the upper end 30A of the engine 30 and the upper end of the muffler 97, the straight line L2 indicating the lower limit of the direct sound may be a straight line that passes through the lower end 75B of the first sidewall exhaust port 75 and is tangent to the first partition 61.

[0040] As shown in FIG. 4, the range in which the engine sound and the sound of the muffler 97 leak to the outside from the first side wall exhaust port 75 is a range relatively high above the ground, so the noise felt by people near the work machine 1 can be reduced.

[0041] 4, the airflow AF that flows into the engine compartment 82 flows in a roughly Z-shape (or S-shape) to reach the first sidewall exhaust port 75 or the second sidewall exhaust port 76, and is exhausted from the first sidewall exhaust port 75 or the second sidewall exhaust port 76 to the outside of the machine compartment 80. This effectively reduces noise caused by engine noise leaking to the outside from the first sidewall exhaust port 75 and the second sidewall exhaust port 76.

[0042] The second sidewall exhaust port 76 is formed below the first sidewall exhaust port 75, and the lateral wall portion 65 has an upper guide surface 65A which is an upper surface that guides air in the engine chamber 82 of the machine chamber 80 to the first sidewall exhaust port 75, and a lower guide surface 65B which is a lower surface that guides air in the engine chamber 82 of the machine chamber 80 to the second sidewall exhaust port 76. In this case, the air in the engine chamber 82 of the machine chamber 80 is smoothly guided to the first sidewall exhaust port 75 and the second sidewall exhaust port 76 by the upper guide surface 65A and the lower guide surface 65B of the lateral wall portion 65, respectively.

[0043] 4, the side wall portion 65 defines the position of the lower end 75B of the first sidewall exhaust port 75 and also defines the position of the upper end 76A of the second sidewall exhaust port 76. The position of the upper end 75A of the first sidewall exhaust port 75 is defined by the top wall 15 or the side wall 14 of the exterior wall 13. The position of the lower end 76B of the second sidewall exhaust port 76 is defined by the upper surface of the counterweight 22, but may also be defined by the side wall 14 of the exterior wall 13.

[0044] The thickness (thickness in the direction of the airflow AF) of the upper surface of the counterweight 22 is greater than the thickness of the sidewall 14 of the outer wall 13. The upstream end of the upper surface of the counterweight 22 in the direction of the airflow AF is located upstream of the airflow AF from the downstream end 61C of the first partition 61. This effectively prevents foreign matter such as rainwater and dust from entering the machine room 80 (engine room 82) through the second sidewall exhaust port 76. The downstream end 61C of the first partition 61 is the downstream end (right end) of the first partition 61 in the airflow AF, and is the downstream end 61C of the lateral wall portion 65.

[0045] In this embodiment, the horizontal wall portion 65 extends in the horizontal direction (right direction) from the vertical wall portion 64 to a position corresponding in the left-right direction to the side surface (right side surface) of the side wall 14 of the outer wall 13. However, the position of the side end (right end) of the horizontal wall portion 65 does not have to be a position corresponding to the side surface (right side surface) of the side wall 14, and may be a position between the upper end of the vertical wall portion 64 and the side surface (right side surface) of the side wall 14.

[0046] The vertical wall portion 64 is not only interposed between the engine 30 and the first sidewall exhaust port 75, but also between the engine 30 and the second sidewall exhaust port 76. In this case, the vertical wall portion 64 is disposed at a position such that the vertical wall portion 64 blocks part or all of the engine sound generated by the engine 30 that travels straight toward the second sidewall exhaust port 76. The vertical wall portion 64 is disposed at a position such that the vertical wall portion 64 covers part or all of the engine 30 when the engine 30 is viewed from the second sidewall exhaust port 76.

[0047] 4, line L3 is a line passing through the downstream end 61C of the first partition 61 and the lower end 61B of the first partition 61 when the working machine 1 is viewed from behind. The lower end 61B of the first partition 61 is located lower than the lower end 76B of the second side wall exhaust port 76.

[0048] In this embodiment, when the work machine 1 is viewed from behind, the engine 30 is located upstream of the straight line L3 in the air flow AF. This makes it possible to effectively prevent engine sound generated from the engine 30 from leaking to the outside through the second sidewall exhaust port 76. Also, in this embodiment, when the work machine 1 is viewed from behind, the muffler 97 is located upstream of the straight line L3 in the air flow AF. This makes it possible to effectively prevent sound generated from the muffler 97 from leaking to the outside through the second sidewall exhaust port 76.

[0049] The work machine 1 further includes a second partition 62 interposed between the hydraulic pump 98 and the multiple mufflers 97. The second partition 62 can separate the area in which the hydraulic pump 98 is arranged from the area in which the multiple mufflers 97 are arranged, so that even if hydraulic oil is splashed from the hydraulic pump 98 to the surrounding area, the hydraulic oil is prevented from adhering to the muffler 97.

[0050] 4, the multiple mufflers 97 include a first muffler 97 and a second muffler 97 disposed above the first muffler 97. The multiple mufflers 97 are disposed directly above the hydraulic pump 98, but do not necessarily have to be disposed directly above the hydraulic pump 98. The multiple mufflers 97 are located downstream of the airflow AF from the engine 30. The hydraulic pump 98 is located downstream of the airflow AF from the engine 30. Note that the multiple mufflers 97 may be located upstream of the airflow AF from the engine 30, and the hydraulic pump 98 may be located upstream of the airflow AF from the engine 30.

[0051] The second partition 62 is disposed between the hydraulic pump 98 and the muffler 97, extending from a position adjacent to the engine 30 toward the lower part of the vertical wall portion 64. In this case, the second partition 62 can not only separate the area in which the hydraulic pump 98 is disposed from the area in which the muffler 97 is disposed, but can also guide the air (air flow AF) around the engine 30 to the vertical wall portion 64 of the first partition 61.

[0052] The second partition 62 has an upstream end 62A, which is one end located adjacent to the engine 30, and a downstream end 62B, which is the other end adjacent to or connected to the lower part of the vertical wall portion 64. The second partition 62 is disposed so as to extend in the horizontal direction from the upstream end 62A to the downstream end 62B toward the vertical wall portion 64 between the hydraulic pump 98 and the muffler 97. The "lateral direction" in which the second partition 62 extends may be a direction parallel to the horizontal direction or may be a direction inclined relative to the horizontal direction. In the specific example shown in FIG. 4, the second partition 62 has a flat plate-like shape, but the shape of the second partition 62 is not limited to the specific example shown in FIG. 4. For example, the second partition 62 may have a curved shape or may have a shape including a flat plate-like portion and a curved portion.

[0053] An upper end 75A of the first sidewall exhaust port 75 is located above the upper end 30A of the engine 30, an upper end 61A of the first partition 61 is located above the upper end 30A of the engine 30, and a lower end 61B of the first partition 61 is located below the upper end 30A of the engine 30. When the first sidewall exhaust port 75 is formed at a position shifted upward relative to the engine 30 in the vertical direction as shown in Fig. 4, the first partition 61 is disposed at a position shifted upward relative to the engine 30 so as to be effectively interposed between the engine 30 and the first sidewall exhaust port 75. This makes it possible to effectively block a portion of the engine sound traveling from the engine 30 toward the first sidewall exhaust port 75.

[0054] The first sidewall exhaust port 75 is formed in the sidewall 14 of the exterior wall 13, and the first partition wall 61 is covered by the top wall 15 of the exterior wall 13 located above the first partition wall 61. Since the first sidewall exhaust port 75 is formed in the sidewall 14 of the exterior wall 13 and the top wall 15 of the exterior wall 13 covers the first partition wall 61 from above, it is possible to prevent foreign matter such as rainwater and dust from entering the machine room.

[0055] As shown in Fig. 3, the right rear and left rear parts of the outer wall 13 have a curved shape when viewed from above, and the first sidewall exhaust port 75 is formed in the right rear part. In this case, at least a portion of the first sidewall exhaust port 75 is formed in the curved right rear part, making it easier to ensure the opening area of ​​the first sidewall exhaust port 75. In the specific example shown in Fig. 3, a portion of the first sidewall exhaust port 75 is formed in the right rear part, and the other portion of the first sidewall exhaust port 75 is formed in the right side part (the right side part of the upper rotating body 3) extending in the front-rear direction.

[0056] Since the outer wall 13 has a first side wall exhaust outlet 75 and a second side wall exhaust outlet 76 in addition to the top wall exhaust outlet 77, it is easier to secure the opening area of ​​the outlet through which the air in the machine room 80 is discharged to the outside of the machine room 80.

[0057] The features of the ceiling wall exhaust port 77 in the work machine 1 according to this embodiment will be described below.

[0058] [First feature] In the work machine 1 shown in Figures 3 and 4, the top wall 15 includes a right side high wall 16R, a low wall 17 located lower than the right side high wall 16R, and a right side adjacent wall 18R located adjacent to the low wall 17 and extending diagonally downward to the left from the right side high wall 16R, and a top wall exhaust port 77 is formed in the low wall 17 to exhaust air from the machine room 80 (specifically, the engine room 82) to the outside of the machine room 80.

[0059] In this work machine 1, the right adjacent wall 18R extends diagonally downward to the left from the right high wall 16R and is located adjacent to the low wall 17, and the top wall exhaust port 77 is formed in this low wall 17. That is, the right adjacent wall 18R has a portion that extends from a position adjacent to the low wall 17 where the top wall exhaust port 77 is formed to the right high wall 16R that is located higher than the low wall 17. Therefore, a part of the engine sound that leaks from the top wall exhaust port 77 to the outside of the machine room 80 is prevented from traveling laterally by the right adjacent wall 18R. This makes it possible to reduce the volume (sound volume) of the engine sound that leaks to the outside from the top wall exhaust port 77 and is transmitted to the right of the work machine 1. Therefore, in this work machine 1, it is possible to reduce noise caused by the engine sound that leaks to the outside from the top wall exhaust port 77 formed in the top wall 15 and travels to the right.

[0060] [Second feature] The work machine 1 having the second characteristic further includes a shielding wall 19 that is arranged in the machine room 80 (specifically, the engine room 82) below the bottom wall 17 and above the engine 30. As shown in Figs. 3 and 4, this shielding wall 19 is arranged in a position that covers the top wall exhaust port 77 from below. In this case, the shielding wall 19 can prevent foreign matter such as rainwater and dust from entering the machine room 80 (specifically, the engine room 82) through the top wall exhaust port 77. As shown in Fig. 3, the shielding wall 19 has an upper surface that overlaps with the top wall exhaust port 77 when viewed from above. The area of ​​the upper surface of the shielding wall 19 is larger than the opening area of ​​the top wall exhaust port 77.

[0061] [Third feature] In a work machine 1 having the third feature, the right adjacent wall 18R extends from the right high wall 16R to the right edge 191 of the shielding wall 19. In this case, the right adjacent wall 18R and the shielding wall 19 are disposed so as to be continuous, which more effectively prevents foreign matter such as rainwater and dust from entering the machine room through the exhaust port. The upper end of the right adjacent wall 18R is located above the low wall 17, and the lower end of the right adjacent wall 18R is located below the low wall 17. It is preferable that the upper surface of the shielding wall 19 and the left side surface of the right adjacent wall 18R are positioned so as to cover the entire ceiling wall exhaust port 77 from below when viewed from above.

[0062] [Fourth feature] In the work machine 1 having the fourth feature, the low wall 17 and the shielding wall 19 define a passage 86 that guides the air in the machine room 80 (specifically, the engine room 82) to the right to the top wall exhaust port 77, and the right side adjacent wall 18R is configured to guide the air guided to the top wall exhaust port 77 upward to the height position of the right side high wall 16R. In this case, the air in the engine room 82 is smoothly guided to the right along the passage 86 to the top wall exhaust port 77, and the air guided to the top wall exhaust port 77 is smoothly guided upward along the right side adjacent wall 18R to the height position of the right side high wall 16R. In addition, a part of the engine sound traveling to the right along the passage 86 hits the right side adjacent wall 18R before reaching the top wall exhaust port 77, and is prevented from traveling to the side by this right side adjacent wall 18R. This makes it possible to more effectively reduce noise caused by the engine sound leaking to the outside from the top wall exhaust port 77 formed in the top wall 15 and traveling to the side.

[0063] The right adjacent wall 18R and the shielding wall 19 have a substantially L-shape in the rear view shown in Fig. 4. In this case, as shown by the dashed-dotted arrow in Fig. 4, the airflow AF that has flowed into the engine compartment 82 flows in a substantially Z-shape (or S-shape) until it reaches the top wall exhaust port 77 and is exhausted from the top wall exhaust port 77 to the outside of the engine compartment 82. This effectively reduces noise caused by the engine sound leaking to the outside from the top wall exhaust port 77.

[0064] [Fifth feature] In a work machine 1 equipped with the fifth characteristic, the top wall exhaust port 77 is defined by the right edge 171 of the low wall 17 and the right side adjacent wall 18R. In this case, since the right side adjacent wall 18R is located immediately to the right of the top wall exhaust port 77, the right side adjacent wall 18R can more effectively block a portion of the engine sound leaking to the outside from the top wall exhaust port 77 from traveling to the right. Part or all of the right edge 171 of the low wall 17 is located to the left of the right side adjacent wall 18R.

[0065] [6th feature] In the work machine 1 having the sixth feature, the top wall 15 further includes not only the right side high wall 16R and the right side adjacent wall 18R, but also the left side high wall 16L located to the left of the low wall 17, and the left side adjacent wall 18L located to the left of the low wall 17 and extending diagonally downward to the right from the left side high wall 16L. The right side adjacent wall 18R and the left side adjacent wall 18L are disposed to the right and left of the low wall 17, respectively, and the top wall exhaust port 77 is formed in the low wall 17 between the right side adjacent wall 18R and the left side adjacent wall 18L. A part of the engine sound leaking to the outside from the top wall exhaust port 77 is prevented from traveling to the right by the right side adjacent wall 18R, and another part of the engine sound leaking to the outside from the top wall exhaust port 77 is prevented from traveling to the left by the left side adjacent wall 18L. This makes it possible to reduce the volume (sound volume) of the engine sound leaking to the outside from the top wall exhaust port 77 and transmitted to the right and left of the work machine 1, respectively. Therefore, noise caused by engine noise leaking to the outside through the top wall exhaust port 77 formed in the top wall 15 and traveling to the right and left can be further reduced.

[0066] An upper edge of the left adjacent wall 18L is located above the bottom wall 17, and a lower edge of the left adjacent wall 18L is connected to the left edge of the bottom wall 17. Since the lower edge of the left adjacent wall 18L and the left edge of the bottom wall 17 are located to the left of the left edge 192 of the shielding wall 19, air from the engine compartment 82 flows smoothly into the passage 86.

[0067] The bottom wall 17 extends rightward from a lower edge of the left adjacent wall 18L toward the right adjacent wall 18R, and the shielding wall 19 extends leftward from a lower edge of the right adjacent wall 18R. A right edge 191 of the shielding wall 19 may be located to the right of the right edge of the bottom wall 17.

[0068] In the specific example shown in FIG. 4, the low wall 17 and the shielding wall 19 are arranged to extend in the horizontal direction, but the extending direction of the low wall 17 and the shielding wall 19 is not limited to the specific example shown in FIG. 4. The extending direction of the low wall 17 and the shielding wall 19 may be parallel to the horizontal direction or inclined relative to the horizontal direction. The extending direction of the right high wall 16R and the left high wall 16L may be parallel to the horizontal direction or inclined relative to the horizontal direction. The right high wall 16R, the left high wall 16L, the low wall 17, the right adjacent wall 18R, the left adjacent wall 18L, and the shielding wall 19 have a flat plate-like shape, but their shapes are not limited to the specific example shown in FIG. 4. Each of the right side high wall 16R, the left side high wall 16L, the low wall 17, the right side adjacent wall 18R, the left side adjacent wall 18L and the shielding wall 19 may have a curved shape or may have a shape that includes a flat portion and a curved portion.

[0069] [Variations] Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments and includes, for example, the following modified examples.

[0070] (A) Exhaust vent In the above embodiment, the outer wall 13 is formed with not only a top wall exhaust port 77 but also a first side wall exhaust port 75 and a second side wall exhaust port 76, but in the work machine of the present disclosure, one or both of the first side wall exhaust port 75 and the second side wall exhaust port 76 are not essential and can be omitted.

[0071] In the above embodiment, the top wall exhaust port 77 formed in the bottom wall 17 is defined by the right edge of the bottom wall 17 and the right adjacent wall 18R, but may be defined by the left edge of the bottom wall 17 and the left adjacent wall 18L, in which case, a part or all of the left edge of the bottom wall 17 is located to the right of the left adjacent wall 18L. Also, in the work machine of the present disclosure, the exhaust port (top wall exhaust port) formed in the top wall may be an opening penetrating the low wall, in which case, the top wall exhaust port is formed in the low wall by being defined by the low wall. That is, in the present disclosure, the top wall exhaust port formed in the bottom wall may be defined by the inner peripheral edge of the opening penetrating the low wall, or may be defined by the side edge of the low wall and the adjacent wall.

[0072] (B) High walls and adjacent walls In the above embodiment, the top wall 15 includes a right side high wall 16R located to the right of the low wall 17, a right side adjacent wall 18R located to the right of the low wall 17 and extending downward or diagonally downward from the right side high wall 16R, a left side high wall 16L located to the left of the low wall 17, and a left side adjacent wall 18L located to the left of the low wall 17 and extending downward or diagonally downward from the left side high wall 16L, but the work machine in the present disclosure is not limited to the specific example such as the above embodiment. In the work machine in the present disclosure, the top wall may have a right side high wall and a right side adjacent wall, but may not have a left side high wall and a left side adjacent wall. Also, the top wall may have a left side high wall and a left side adjacent wall, but may not have a right side high wall and a right side adjacent wall. Also, the top wall may have one or both of a front side high wall located in front of the low wall and a rear side high wall located behind the low wall. Specifically, the top wall may include a front high wall located in front of the low wall, and a front adjacent wall located adjacent to the low wall and extending downward or diagonally downward from the front high wall. The top wall may also include a rear high wall located behind the low wall, and a rear adjacent wall located adjacent to the low wall and extending downward or diagonally downward from the rear high wall.

[0073] In the above embodiment, the right side adjacent wall 18R extends diagonally downward to the left from the right side high wall 16R, and the left side adjacent wall 18L extends diagonally downward to the right from the left side high wall 16L, but the right side adjacent wall 18R may extend downward from the right side high wall 16R, and the left side adjacent wall 18L may extend downward from the left side high wall 16L.

[0074] (C) Shielding walls In the embodiment described above, the work machine 1 is provided with a shielding wall 19, but in the work machine of the present disclosure, the shielding wall is not essential and can be omitted. In addition, a sound absorbing material 193 may be attached to the underside of the shielding wall 19, for example, as shown in FIG. [Explanation of symbols]

[0075] 1: Work machine 3: Upper rotating body 13: Exterior wall 14: Side wall 15: Ceiling wall 16:High wall 17: Low wall 18: Adjacent wall 19: Shielding wall 30: Engine 30A: Top of engine 61: 1st bulkhead 61A: Top of the first bulkhead 61B: Lower end of first bulkhead 61C: Side end of first bulkhead 62:Second bulkhead 62A: upstream end of second bulkhead 62B: downstream end of second bulkhead 64:Vertical wall part 65: Side wall 65A: Upper guide surface of side wall 65B: Lower guide surface of side wall 75: First side wall exhaust port 75A: Top end of first side wall exhaust port 75B: Lower end of first side wall exhaust port 76: Second side wall exhaust port 76B: Lower end of second side wall exhaust port 77: 3rd exhaust port 80: Machine room 81: Air intake chamber 82: Engine room 97: Muffler 98: Hydraulic pump AF: Air flow

Claims

1. An outer wall surrounding the machine room; an engine disposed in the engine room, the outer wall includes a top wall, the top wall includes a high wall, a low wall located lower than the high wall, and an adjacent wall located adjacent to the low wall and extending downward or diagonally downward from the high wall, and the low wall is formed with an exhaust port for discharging air from the machine room to the outside of the machine room.

2. a shielding wall disposed in the engine room below the bottom wall and above the engine, The work machine according to claim 1 , wherein the shielding wall is disposed in a position so as to cover the exhaust port from below.

3. The work machine of claim 2 , wherein the adjacent wall extends from the high wall to the shield wall.

4. the bottom wall and the shielding wall define a passage for laterally directing air in the machine room to the exhaust port; 4. The work machine according to claim 2 or 3, wherein the adjacent wall is configured to guide air guided to the exhaust port upward to a height position of the high wall.

5. The work machine according to any one of claims 1 to 3, wherein the exhaust port is defined by a side edge of the bottom wall and the adjacent wall.

6. the high wall is a right-side high wall located to the right of the low wall, and the adjacent wall is a right-side adjacent wall located to the right of the low wall and extending downward or obliquely downward from the right-side high wall, The work machine according to any one of claims 1 to 3, wherein the top wall further includes a left side high wall located to the left of the low wall, and a left side adjacent wall located to the left of the low wall and extending downward or diagonally downward from the left side high wall.

7. The work machine of claim 1 , wherein the high wall is located to the right, left, in front or behind the low wall.

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