JP2005145114A - Engine hood of construction machinery, engine room structure of construction machinery, and cooling device of construction machinery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce noise in an engine hood of construction machinery, an engine room structure of construction machinery, and a cooling device of construction machinery. <P>SOLUTION: This engine hood of construction machinery for opening/closing a maintenance opening formed in the upper wall surface 22 of an engine room storing an engine 26, a cooling fan 25, and a cooling package 24 installed on the upstream side of the cooling fan 25 in the axial flow direction Y, the maintenance opening comprises a swelled plate 41 formed to be swelled upward relative to the upper wall surface 22 when the maintenance opening is closed and having cooling air discharge ports 41ba and 42ea formed on the downstream side of the cooling fan in the axial direction Y and in the swing flow direction. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an engine hood that opens and closes a maintenance port on an upper wall of an engine room of a construction machine used in various fields such as a construction site, a harbor, and a factory, and an engine room structure and a construction machine of a construction machine using the same. The present invention relates to a cooling device.

  Today, various construction machines such as traveling construction machines such as excavators and wheel loaders and stationary construction machines such as cranes are used in various fields such as construction sites, harbors, factories, and the like. The structure of these construction machines is, for example, a hydraulic excavator that is a traveling construction machine, as shown in FIG. 11, a lower traveling body 101, and an upper revolving body 102 that is pivotably disposed above the lower traveling body 101. The upper revolving unit 102 is provided with three parts including a work device 103 that performs various work. Of these, the upper swing body 102 has a counterweight 102-1 disposed behind the machine body, and an engine room 102-2 disposed in front of the machine body of the counterweight 102-1.

Here, the engine room 102-2 will be described with reference to FIG. FIG. 12 is a diagram showing a configuration of a general engine room, and is a schematic cross-sectional view of the engine room viewed from the front of the body.
In the engine room 102-2, devices such as the engine 106 and the hydraulic pump 108 are disposed, and the working device 103 (see FIG. 11) is operated by the hydraulic pressure generated by driving the hydraulic pump 108 by the engine 106.

  Construction machines are generally used in harsh environments such as excavation of rocks in dams, tunnels, rivers, roads, etc., and demolition of buildings and buildings. In such environments, equipment such as the engine 106 and the hydraulic pump 108 are used. The load applied to the engine is high, and the engine temperature and the oil temperature are likely to rise. For this reason, in these construction machines, as shown in FIG. 12, a cooling package 104 composed of a relatively large-capacity radiator, an oil cooler, or the like is provided in the flow path of the cooling air generated by the fan 105 driven by the engine 106. In addition, engine cooling water and hydraulic oil are cooled by these cooling packages 104 (see, for example, Patent Document 1).

That is, external air (cooling air) is sucked from the upper opening 110 of the radiator room 102A in which the cooling package 104 is installed by the rotation of the fan 105, and this air passes through the core of the fin-shaped cooling package 104. In doing so, the engine cooling water and hydraulic oil are cooled.
The main engine room 102B is provided with an opening 111 on the upper surface and an opening 112 on the lower surface at a predetermined distance from the fan 105 in the fan axial flow direction (left-right direction in FIG. 12). Yes. The opening 111 on the upper surface includes a plurality of openings formed in a mesh shape or a louver shape, and is formed with a relatively large width in the fan axial flow direction. On the other hand, the opening 112 on the lower surface is formed as a single opening having a relatively large area.

The pump room 102C in which the hydraulic pump 108 is installed is provided with an opening 113 on the upper surface and an opening 114 on the lower surface. These openings 113 and 114 are openings of the main engine room 102B. Like 111, it consists of a plurality of openings formed in a mesh shape or a louver shape.
Air that has been heated to a high temperature by cooling the engine coolant or hydraulic oil is discharged to the outside from the exhaust openings 111 and 112 of the main engine room 102B, or passes through the main engine room 102B, and the air in the pump room 102C. The gas is discharged from the exhaust openings 113 and 114 to the outside.

By the way, especially in the hydraulic excavator, the flow of air discharged from the fan 105 has almost no component in the fan axial direction, and the component in the centrifugal direction and the component in the swirl direction (hereinafter collectively referred to as the centrifugal / swirl direction component). Has been confirmed to be the main component.
Hereinafter, the reason for this will be described with reference to FIGS.
In the case of a hydraulic excavator, the space where a radiator, an engine, and the like can be mounted inside the upper swing body 102 is as shown in FIG. 13A, and is narrower than the space of other construction machines as shown in FIG. 13B. In particular, the cross-sectional area (cross section perpendicular to the fan axial flow direction) is reduced. This is because if the height of the engine room is increased, the rear view from the driver's seat in front of the engine room is obstructed, and if the width of the engine room (the length of the front and rear of the construction machine) is increased, the captain will This is because it becomes longer and the turning radius at the rear end of the construction machine becomes larger, which is inconvenient for use in a narrow field.

  Thus, in the hydraulic excavator, the thickness of the cooling package 104 (dimension with respect to the direction in which the cooling air travels) is increased, and the contact area between the cooling package 104 and the cooling air, that is, the cooling package 104 is reduced. The cooling performance is ensured. As a result, the pressure resistance received when the cooling air passes through the cooling package 104 becomes relatively large.

  In construction machines, axial fans are generally used as cooling fans in order to reduce cost and size. FIG. 14 is a schematic diagram showing a performance curve of a general axial fan. As apparent from the performance curve L, in the axial fan, generally, the fan air volume V per unit time tends to decrease as the pressure loss ΔP on the upstream side of the fan increases. The fan air volume V is the amount of movement of the cooling air from the upstream side of the fan to the downstream side of the fan. Therefore, the axial flow that is a linear flow from the upstream side of the fan to the downstream side of the fan increases as the pressure loss ΔP on the upstream side of the fan increases. Directional flow is particularly difficult to obtain.

For this reason, in the low pressure loss region R _L where the pressure loss ΔP on the upstream side of the fan is less than the predetermined value ΔP ₀ , the flow of the cooling air becomes as shown in FIGS. In the high pressure loss region R _H where the loss ΔP is equal to or greater than the predetermined value ΔP _0, the flow of the cooling air is as shown in FIGS. 16 (a) and 16 (b). is a diagram showing by matching the axial direction, in FIG. 15 (a) and 15 FIG. 15 (a), the show lower only the rotation center line C _L of the cooling fan].

That is, since the fan air volume is relatively large in the low pressure loss region _RL , as shown in FIG. 15A, the fan upstream side is relatively large as represented by the vector F _{IN, 1.} An axial flow of air flow is generated, and the flow as represented by the vector F _{OUT, 1} on the downstream side of the fan, that is, the axial flow direction component vector F _{A, 1} dominates rather than the centrifugal / swirl direction component vector F _{C, 1.} Flow will occur. Then, the air volume becomes larger as it goes to the centrifugal side as shown by a vector in FIG.

On the other hand, since the fan air volume is relatively small in the high pressure loss region _RH , as shown in FIG. 16 (a), a relatively small amount as shown by the vector F _{IN, 2} on the upstream side of the fan. Only the axial flow is generated, and on the downstream side of the fan _{, the} flow shown by the vector F _{OUT, 2} , that is, the centrifugal / swirl direction component vector F _{C, 2} is more dominant than the axial flow direction component vector F _{A, 2.} A flow is generated, and the air volume becomes larger toward the centrifugal side as indicated by a vector in FIG.

Such a relationship between the pressure loss ΔP on the upstream side of the fan and the flow of cooling air on the downstream side of the fan has been confirmed by experiments and simulations.
As described above, since the hydraulic excavator has a thick cooling package, the pressure loss ΔP on the upstream side of the fan is large and the cooling fan is used in the high pressure loss region. The flow component of the cooling air on the fan outlet side is centrifugal / The turning direction component becomes dominant.

  However, in the prior art shown in FIGS. 11 and 12, as described above, the exhaust opening 111 having a plurality of openings formed in a mesh shape is spaced from the fan 105 in the fan axial flow direction. Since the cooling air sucked into the main engine room 102B is forced to flow in the axial direction before being discharged, the fan is forced to flow in the axial direction. Is done.

In other words, in this prior art, air having a centrifugal / swirl direction component as a main component of the flow is forced to flow in the axial direction, so that the pressure loss experienced by the air due to the generation of turbulent flow is relatively small. There is a problem that the air is not smoothly discharged after passing through the cooling package 104 (discharge efficiency is low).
In order to improve the exhaust efficiency, it is conceivable to increase the opening area of the main engine room 102B. In this case, however, noise (wind noise generated when engine noise or cooling air passes through the cooling package 104, etc.). Leakage to the outside), and a new problem arises.

Therefore, Patent Document 2 discloses a construction machine as shown in FIG. 17 as a technique for improving the efficiency of exhausting cooling air from the engine room and reducing noise. In this construction machine, an inlet 131 for cooling air is provided on the upper surface of the engine room 130, and a cooling air discharge passage (fan air flow channel, fan air flow duct) is formed on the upper surface and both side surfaces (vehicle front and rear surfaces) of the engine room 130. ) 132 to 134 are provided, and the entrance (the left end portion in FIG. 17) of the cooling air passage is positioned near the outer periphery of the cooling fan. With such a configuration, the cooling air blown from the cooling fan in the centrifugal / swirl direction is efficiently discharged from a small opening, and an increase in noise from the engine room 130 is prevented.
Japanese Utility Model Publication No. 3-83324 JP 2001-193102 A

However, the prior art shown in FIG. 17 has the following problems.
That is, similarly to the above-described prior art shown in FIG. 11, the discharge ports 132a and 134a of the cooling air passages 132 and 134 are provided on the upper surface of the engine room. Noise will be emitted toward the. Although it is possible to suppress noise emitted from construction machinery, for example, by enclosing the work place with a shield, providing such a shield for the noise emitted vertically upward requires large-scale work. It is not realistic, and part of the noise in the horizontal direction and the noise in the vertically downward direction are mainly absorbed by the ground, etc., but there is no such absorber for the noise emitted in the vertically upward direction. Its propagation range is extremely wide.

  The present invention has been made in view of the above problems, and an object thereof is to provide an engine hood for a construction machine, an engine room structure for the construction machine, and a cooling device for the construction machine that can reduce noise.

  In order to achieve the above object, an engine hood for a construction machine according to claim 1 of the present invention is an engine room that houses an engine, a cooling fan, and a cooling package installed upstream in the axial direction of the cooling fan. An engine hood for a construction machine that opens and closes a maintenance port formed on a wall surface, and has a shape that bulges upward with respect to the upper wall surface in a closed posture in which the maintenance port is closed, and is downstream of the axial flow direction. It is characterized by having a bulging plate in which the cooling air discharge port is formed at each of the part and the downstream part in the swirl flow direction of the cooling fan.

  An engine hood for a construction machine according to a second aspect of the present invention is the engine hood for a construction machine according to the first aspect, in which the space is opened with respect to the upper portion of the bulging plate and below the discharge port. It is characterized by comprising a bottom plate assembled to the bulging plate, a space between the bulging plate and the bottom plate, and a communication port for communicating the engine room.

The engine hood for a construction machine according to a third aspect of the present invention is the engine hood for a construction machine according to the second aspect, characterized in that the communication port is disposed above the cooling fan.
The engine hood for a construction machine according to a fourth aspect of the present invention is the engine hood for the construction machine according to the second or third aspect, wherein the bottom plate is located upstream of the inner wall surface of the bulging plate in the axial direction of the fan. The communication port is assembled to the bulging plate with a gap, and the communication port is formed by the gap.

The engine hood of the construction machine according to claim 5 of the present invention is the engine hood of the construction machine according to claim 2 or 3, wherein the bottom plate is located upstream of the inner wall surface of the bulging plate in the fan swirl flow direction. The communication port is assembled to the bulging plate with a gap, and the communication port is formed by the gap.
The engine hood of the construction machine of the present invention according to claim 6 is the engine hood of the construction machine according to any one of claims 1 to 5, wherein the wall surface on the upstream side in the swirl flow direction of the bulging plate is: It is characterized by being formed in a curved shape along the swirl flow direction.

  The engine room structure of a construction machine according to claim 7 of the present invention is a structure of an engine room of a construction machine that houses an engine, a cooling fan, and a cooling package installed upstream in the axial direction of the cooling fan. A maintenance port is formed on the upper wall surface forming the engine room, and the engine hood of the construction machine according to any one of claims 1 to 6 is attached to the upper wall surface with respect to the maintenance port. It is a feature.

  An engine room structure of a construction machine according to claim 8 of the present invention is a structure of an engine room of a construction machine that houses an engine, a cooling fan, and a cooling package installed upstream in the axial direction of the cooling fan. A maintenance port is formed in the upper wall surface of the machine body that forms the engine room, and the engine hood of the construction machine according to claim 1 is attached to the maintenance port, and the engine hood is attached to the machine body. In a closed posture with the maintenance port closed, a bottom plate connected to the bulging plate below the discharge port so as to open a space with respect to the upper portion of the bulging plate, and the bulging plate and the bottom portion It is characterized by comprising a space between the plate and a communication port for communicating with the engine room.

The engine room structure of the construction machine of the present invention according to claim 9 is the engine room structure of the construction machine according to claim 7 or 8, wherein the wall surface on the upstream side in the swirl flow direction of the bulging plate is in the swirl flow direction. It is characterized by being formed in a curved shape along the line.
The engine room structure of the construction machine according to claim 10 of the present invention comprises an engine, a cooling fan, and a cooling package installed on the upstream side in the axial direction of the cooling fan, and the internal space functions as a cooling air passage. An engine room structure of a machine, comprising: an opening formed in an upper wall surface forming the engine room; and a portion downstream of the upper wall surface attached to the opening so as to cover the opening And a duct having a discharge port for the cooling air at each downstream portion in the swirling flow direction of the cooling fan.

An engine room structure for a construction machine according to an eleventh aspect of the present invention is the engine room structure for a construction machine according to the tenth aspect, wherein the opening is disposed above the cooling fan.
The engine room structure of the construction machine according to claim 12 of the present invention is the engine room structure of the construction machine according to claim 10 or 11, wherein the wall surface upstream of the duct in the swirl flow direction is along the swirl flow direction. It is characterized by being formed in such a curved shape.

  A cooling device for a construction machine according to a thirteenth aspect of the present invention comprises a cooling air passage formed by an internal space of an engine room, a cooling fan, and a cooling package installed upstream in the axial direction of the cooling fan. A cooling device for a construction machine, comprising: an opening formed on an upper wall surface forming the engine room; and an outer side of the upper wall surface so as to cover the opening, and downstream in the axial direction And a duct having a cooling air discharge port at a downstream side in the swirling flow direction of the cooling fan.

A construction machine cooling apparatus according to a fourteenth aspect of the present invention is the construction machine cooling apparatus according to the thirteenth aspect, characterized in that the opening is disposed above the cooling fan.
A construction machine cooling device according to a fifteenth aspect of the present invention is the construction machine cooling device according to the thirteenth or fourteenth aspect, wherein the upstream wall surface of the duct in the swirl flow direction is along the swirl flow direction. It is characterized by being formed into a curved shape.

  According to the present invention, the cooling air discharge port of the duct (or engine hood functioning as a duct) is provided in the downstream portion in the fan axial flow direction and the downstream portion in the fan swirl flow direction, respectively. Therefore, it is possible to smoothly discharge the cooling air having a dominant flow component in the centrifugal / swirl direction and the cooling air having a relatively large flow component in the axial flow direction, which occupies most of the cooling air discharged from the cooling fan. As a result, cooling air can be discharged efficiently with a small opening area of the discharge port, and noise can be reduced.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In addition, in each figure of FIGS. 1-10, the arrow X in a figure shows the front-back direction (henceforth an engine room width direction) of a construction machine, and the arrow Y in a figure shows the left-right direction (henceforth, following) of a construction machine. Also referred to as the fan axial flow direction).
In the following embodiments, an example in which the present invention is applied to a hydraulic excavator as a construction machine will be described.

(1) First Embodiment A construction machine to which an engine hood, an engine room structure, and a cooling device as a first embodiment of the present invention are applied will be described with reference to FIG. FIG. 1 is a schematic perspective view showing the overall configuration of the construction machine according to the first embodiment of the present invention.
The construction machine is composed of three parts: a lower traveling body 1, an upper revolving body 2 disposed on the upper side of the lower traveling body 1, and a work device 3 provided on the upper revolving body 2 for performing various operations. It is configured. Among these, the upper revolving body 2 has a counterweight 2A disposed behind the airframe, and an engine room 2B disposed in front of the airframe of the counterweight 2A. A maintenance port 22a is provided on the ceiling surface so that the engine in the engine room 2B can be maintained, and an engine hood 40 for opening and closing the maintenance port 22a is attached. In FIG. 1, the engine hood 40 is in an open position with the maintenance port 22a open.

Next, the structure of the engine room 2B as the first embodiment of the present invention will be described with reference to FIG. 2A and 2B are views showing the structure of the engine room 2B. FIG. 2A is a schematic cross-sectional view as seen from the front of the airframe, and FIG. 2B is a schematic cross-sectional view taken along line AA in FIG.
In the engine room 2B, the engine 26 is installed with its crankshaft directed in the left-right direction Y of the fuselage, and an axial cooling fan 25 is disposed on the right side of the engine 26 in FIG. . The cooling fan 25 is installed in such a posture that its axial flow direction coincides with the left-right direction Y of the airframe, and sucks outside air from an introduction opening 22c formed in the engine room ceiling surface (upper wall surface) 22. Outside air is circulated as cooling air through a cooling air passage formed by the internal space of the engine room 2B.

  Here, the cooling fan 25 is configured to send cooling air in the direction to the left in FIG. 2A, and as indicated by an arrow D, the fan blade 25a as viewed from the upstream side in the fan axial flow direction. Is designed to rotate clockwise. Here, the cooling fan 25 is an engine drive type mechanically coupled to the engine crankshaft, but is not limited to this, and may be a hydraulic drive type.

On the upstream side in the axial direction of the cooling fan 25 (right side in FIG. 2A), a cooling package 24 including a radiator, an oil cooler, and the like is installed, and the downstream side in the fan axial direction of the engine 26 [FIG. On the left side in (a), a hydraulic pump 27 mechanically connected to the engine crankshaft is installed.
The interior of the engine room 2B is partitioned between the cooling package 24, the engine 26, and the hydraulic pump 27. The radiator room 2Ba in which the radiator (cooling package 24) is installed, the engine 26, and the cooling fan 25 are provided. The main room (hereinafter referred to as the main engine room) 2Bb and the pump room 2Bc in which the hydraulic pump 27 is installed are divided.

An engine hood 40 is attached to the upper wall surface 22 of the engine room 2B so as to be openable and closable, and the engine 26 and the like are inspected via a maintenance port 22a (see FIG. 1) that appears when the engine hood 40 is opened upward. Maintenance such as parts replacement, repair and cleaning can be performed.
Here, the structure of the engine hood 40 will be described with reference to FIGS.

  FIG. 3 is a partially cutaway view of the engine hood 40 and is a schematic perspective view seen from obliquely above. FIG. 4 is a schematic view of the main part of the upper swing body with the engine hood 40 closed as seen obliquely from above. FIG. 5 is a partially cutaway view of the main body 21 that constitutes the engine room 2B as its internal space, and shows the main part of the upper revolving body with the engine hood 40 open from obliquely above. It is the seen typical perspective view.

The engine hood 40 includes a flat bottom plate 42 and a bulging plate 41 attached to the upper side of the bottom plate 42.
The bottom plate 42 forms a ceiling surface of the main engine room 2Bb, and is attached to the main body 21 through a hinge (not shown). The bottom plate 42 is centered on one side (here, the rear side) on which the hinge is attached. Vertically between a closed posture (the posture in FIGS. 3 and 4) that closes the maintenance port 22a in a horizontal posture and an open posture (the posture in FIG. 5) that opens the maintenance port 22a in a standing posture It is configured to be swingable.

  Further, the bottom plate 42 is assembled to the bulging plate 41 with a gap 44 with respect to the wall surface 41 d on the upstream side in the fan axial direction of the bulging plate 41. The air passage 43 (which will be described later) formed between the bottom plate 42 and the inside of the main engine room 2Ba functions as a communication port. The gap 44 has a slit shape that is long in the engine room width direction X, and is positioned above the cooling fan 25 of the cooling fan 25.

The bulging plate 41 is fixed to the bottom plate 42. Here, the engine room width direction X is set to be approximately the same length as the bottom plate 42, and both end edges of the engine room width direction X are set to the engine room width of the bottom plate 42. It is fixed to the bottom plate 42 so as to coincide with both end edges in the direction X.
The bulging plate 41 has a central portion (main surface) 41 a that bulges with respect to its lower edge portion that contacts the bottom plate 42 and thus with respect to the bottom plate 42. Specifically, the bulging plate 41 has a substantially trapezoidal cross section and has a substantially box-shaped outline. The bulging plate 41 has a rectangular main surface 41a and four surroundings of the periphery of the main surface 41a. It consists of wall surfaces 41b-41e. The bulging plate 41 is assembled to the bottom plate 42 with a space 43 between the main surface 41 a and the bottom plate 42, and here, the main surface in the assembled state of the bulging plate 41 and the bottom plate 42. 41 a is in a posture parallel to the bottom plate 42.

  Further, the wall surface 41c on the upstream side of the fan swirl flow has a curved shape (shape like an arc centered on the fan rotation axis) along the fan swirl flow. Further, a plurality of discharge ports 41ba are arranged in parallel along the engine room width direction X on the surface 41b on the downstream side in the fan axial flow direction, and the discharge ports 41ea on the surface 41e on the downstream side in the fan swirl flow direction. Are arranged side by side. Here, although the shape of each discharge port 41ba and 41ea is circular, it is not limited to circular.

In the closed position where the engine hood 40 closes the maintenance port 22a, the communication port (hereinafter also referred to as opening) 44 serves as an inlet between the main surface 41a of the bulging plate 41 and the bottom plate 42, and the above A cooling air passage 43 is formed with the outlet 41ba formed in the bulging plate 41 as an outlet.
Reference numeral 45 denotes a partition plate, which is positioned above the cooling package 24 in the closed posture in which the maintenance port 22a of the engine hood 40 is closed, and is placed on the intake side (before passing through the cooling package 24). The partition is vertically divided between the side with the relatively cool cooling air and the exhaust side (the side with the relatively cool cooling air after passing through the cooling package 24) (not shown in FIG. 4).

  Referring again to FIGS. 2A and 2B, in such a configuration, the cooling fan 25 is operated to take in the cooling air from the engine room introduction opening 22c into the airframe body (cooling air passage). The outside air passes through the cooling package 24 and then flows from the opening 44 into the air passage 43 formed between the bulging plate 41 and the bottom plate 42, and the air passage 43 smoothly discharges the outlet 41 ba, It is guided to 41ea, discharged to the outside of the machine, and cools the cooling water and hydraulic oil of the hydraulic pump when passing through the cooling package 24.

That is, the cooling device according to the present embodiment includes the engine room introduction opening 22c, the cooling air passage (the space in the body body 21, that is, the chambers 2Ba, 2Bb, 2Bc), the cooling package 24, the cooling fan 25, and the engine hood 40. It is composed.
A part of the cooling air flowing into the engine room 2B is a little, but a connecting portion 27a between the engine 26 and the hydraulic pump 27, and a partition wall (fire wall) 28 between the main engine room 2Bb and the pump room 2Bc. And flow into the pump room 2Bc. For this reason, mesh-like discharge ports 22b and 23b are supplementarily provided on the upper wall surface 22 and the lower wall surface 23 so as to face the pump room 2Bc, and cooling air flows from these openings 22b and 23b to the outside of the machine. It is supposed to be discharged.

The engine hood of a construction machine, the engine room structure of the construction machine, and the cooling device according to the first embodiment of the present invention are configured as described above, and cooling air is supplied as shown in FIGS. Is distributed.
In other words, the operation of the cooling fan 25, outside air is sucked from the opening 22c into the engine room 2B in as cooling air as indicated by the arrow F _1. The sucked cooling air passes through the cooling package 24 as indicated by arrows F _{2 to} F ₄ , and at this time, the engine cooling water and the pump hydraulic oil flowing in the cooling package 24 are cooled.

As described in the prior art, since the pressure loss of the cooling package 24 is generally relatively large, the cooling air sent from the cooling fan 25 flows as indicated by arrows F ₅ and F ₆ , and the cooling fan The main component of the cooling air flow 25 is a centrifugal / swirl direction component. That is, most of the cooling air sent out from the cooling fan 25 flows in a substantially centrifugal direction linearly or while turning.

Therefore, in the present embodiment, an inlet (communication port) 44 of the air passage 43 formed by the engine hood 40 is disposed on the upper surface of the wall surface of the body body at the place where the cooling air is directed, so that the air is sent out from the cooling fan 25. As shown by the arrow F ₆ , most of the cooling air that has flowed into the air passage 43 formed between the bulging plate 41 and the bottom plate 42 of the engine hood 40 without receiving direct resistance, Guided by this air passage 43, it is smoothly discharged from the discharge port 41ea on the downstream side in the fan swirl flow direction to the outside of the machine. Further, the cooling air having a strong flow component in the axial direction as compared to the cooling air indicated by the arrow F ₆ while having the centrifugal / swirl direction component as the main component of the flow is guided by the air passage 43 and indicated by the arrow F ₇ . As shown, the air is smoothly discharged from the discharge port 41ba on the downstream side in the fan axial direction to the outside of the machine.

Also, among the cooling air flowing as a main component the flow of the centrifugal / turning direction toward the opening 44, towards the fan swirling flow upstream wall 41c of the bulged plate 41 as indicated by arrow F ₅ in FIG. 2 (b) The cooling air flowing in the vertical direction flows upward, but is deflected toward the discharge port 41ea on the downstream side in the fan swirl flow direction by the curved shape of the wall surface 41c, and is smoothly discharged from the discharge port 41ea.

As described above, the cooling air discharged from the cooling fan 25 is guided by the air passage 43 having the opening 44 arranged on the outer periphery of the cooling fan as an inlet, whereby the cooling air discharge efficiency can be improved.
As a result, the total opening area of the discharge ports 41ba and 41ea can be made relatively small, and wind noise generated when engine noise and cooling air pass through the fan blades and the cooling package 24 (hereinafter referred to as “engine noise and the like”). Leakage to the outside, that is, noise, and the pressure loss of the cooling air can be reduced, and the cost of the cooling fan 25 can be reduced to reduce the cost. Alternatively, since the cooling air discharge efficiency is improved, it is possible to increase the air volume even when the cooling fan 25 having the same specification is used, and a compact cooling package having a smaller heat exchange area than the conventional one is used. Is possible.

The cooling air discharged from the engine room 2B is guided by the air passage 43 formed by the engine hood 40, is deflected in the horizontal direction, and is smoothly discharged to the outside of the machine. Engine sound and the like leaking to the outside through the attitude air passage 43 also propagates in the horizontal direction as indicated by the broken arrow N ₁ .
It is possible to suppress the noise emitted from the construction machine in the horizontal direction, for example, by enclosing the work place with a shield, but providing such a shield against the noise emitted vertically upward is a major work. However, some of the noise emitted in the horizontal direction and the noise emitted vertically downward are absorbed by the ground, etc., but such absorbers are used for noise emitted vertically upward. The propagation range is extremely wide.

Therefore, the propagation range (the propagation direction and the propagation distance) can be narrowed by setting the noise propagation direction in this horizontal direction.
Further, engine noise transmitted through the air passage 43 as indicated by the arrow N ₁ is absorbed and attenuated by the bulging plate 41 and the bottom plate 42 forming the air passage 43.
In addition, part of the engine sound or the like is transmitted through the bottom plate 42 and the bulging plate 41 as indicated by the broken arrow N ₂ in FIG. 2B. At this time, the bottom plate 42 and the bulging plate 41 is attenuated. That is, as indicated by the arrow N ₂ , the engine sound that propagates outside the machine is shielded and attenuated by the two wall surfaces of the bottom plate 42 and the bulging plate 41 from the outside of the machine.

In addition, by being guided to the air passage 43, the cooling air is discharged from the position separated from the engine room introduction opening 22c to the outside of the apparatus rather than being directly discharged from the opening 44 to the outside of the apparatus. The cooling air is discharged toward the side away from the engine room introduction opening 22c. As a result, it is possible to prevent the cooling air (hot air) having a high temperature after heat exchange with the cooling package 24 discharged to the outside of the machine from being introduced again from the engine room introduction opening 22c (entrainment of hot air).
Also in this respect, cooling of the cooling package 24 and thus cooling of engine cooling water, pump hydraulic oil, etc. can be performed efficiently, and the cooling package can be made compact.

(2) Second Embodiment An engine hood, an engine room structure, and a cooling device as a second embodiment of the present invention will be described with reference to FIGS.

  FIGS. 6 to 8 are views showing an engine hood, an engine room structure, and a cooling device according to the present embodiment. FIG. 6 is a view showing the structure of the engine room 2B, and FIG. FIG. 7B is a schematic BB cross-sectional view of FIG. 7A, and FIG. 7 is a partially cutaway view of the engine hood 50, and is a schematic perspective view seen obliquely from above. FIG. 8 is a schematic perspective view of the main part of the upper revolving body with the engine hood 50 closed, as viewed obliquely from above. FIG. It is the typical perspective view which looked at the upper revolving superstructure main part of the open state from diagonally upward. In addition, about the components mentioned in the said 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

The engine hood 50 of the present embodiment is configured as shown in FIGS. 6 to 8 and includes a hood main body 51 and an additional plate (bottom plate) 54.
The hood main body 51 opens and closes the maintenance port 22a, and is attached to the main body 21 through a hinge (not shown). The hood main body 51 is centered on one side where the hinge is attached (here, the rear side). It can swing up and down between a closed posture in which the maintenance port 22a is closed in a horizontal posture and an open posture in which the maintenance port 22a is opened in a standing posture.

The hood main body 51 has a bulging portion (bulging plate) 52 and a flat plate portion 53 that are arranged in the fan axial flow direction, and the bulging portion 52 is directed upstream in the fan axial flow direction and the flat plate portion 53 is directed to the fan axial flow. It is attached to the fuselage body 21 in a posture directed toward the downstream side.
The bulging portion 52 has a shape in which a central portion (main surface) 52 a bulges with respect to the flat plate portion 53. Specifically, the bulging portion 52 has a substantially trapezoidal cross section and a substantially box-shaped outline, and surrounds a quadrilateral main surface 52a and the periphery of the main surface 52a. The side wall surfaces 52b to 52e are made to have the lower surface coincident with the lower surface of the flat plate portion 53. Further, the side wall surface 52c on the upstream side of the fan swirl flow has a curved shape along the fan swirl flow (shape like an arc centered on the fan rotation axis).

  The quadrilateral additional plate 54 is attached inside the bulging portion 52. The dimension of the additional plate 54 in the fan axial flow direction Y is set to be smaller than the same dimension of the bulging portion 52 by the same dimension of the cooling package 24, and the dimension in the engine room width direction X is the bulging portion 52. The outer peripheral edge on the downstream side in the fan axial flow direction and the downstream side in the fan swirl flow direction is set as the inner periphery on the downstream side in the fan axial flow direction and the downstream side in the fan swirl flow direction. It is fixed to the bulging portion 52 so as to coincide with the lower edge.

The bulging portion 52 has a plurality of discharge ports 52ba arranged in parallel along the engine room width direction X in the range where the additional plate 54 is connected to the surface 52b downstream of the fan axial flow direction. A plurality of discharge ports 52ea are arranged in parallel along the fan axial flow direction Y in a range where the additional plate 54 is connected to the side wall surface 52e on the downstream side in the swirling flow direction.
The shape of the discharge port 52ba is circular here, but is not limited thereto. Similarly, the shape of the discharge port 52ea is circular here, but is not limited thereto.

Reference numeral 57 denotes a partition plate, which is positioned above the cooling package 24 in a closed posture in which the maintenance port 22a of the engine hood 50 is closed, and vertically extends in the bulging plate 51 between the intake side and the exhaust side. It is designed to partition (omitted in FIG. 8).
In such a configuration, in a closed posture in which the maintenance port 22a of the engine hood 50 is closed, an opening 55 is formed between the bulging portion 52 and the additional plate 54 so as to face the engine room 2B. The opening 55 functions as a communication port that allows the engine room 2 </ b> Bb and the inside of the engine hood 50 to communicate with each other, and cooling air after passing through the cooling package 24 flows into the engine hood 50. That is, the air passage 56 having the opening 55 as an inlet and the exhaust ports 52ba and 52ea as outlets is formed in the bulging portion 52.
Since other configurations are the same as those of the first embodiment, description thereof is omitted.

In the engine hood of a construction machine, the engine room structure of the construction machine, and the cooling device according to the second embodiment of the present invention, as shown in FIGS. 6A and 6B, the cooling air discharged by the cooling fan 25 is since the main component of flows as indicated by the arrow F ₁₀ is a centrifugal / turning direction, the air passage 56 formed inside the bulging portion 52, and side wall surfaces of the fan swirling flow downstream, the fan shaft By providing the exhaust ports 52ba and 52ea in the direction of the cooling air, the cooling air can be efficiently discharged with a small opening area of the exhaust ports 52ba and 52ea. Can do.

Further, if there is no additional plate 54, the cooling air whose swirling direction is the main component of the flow is caused to circulate toward the fan rotation center C _F side as indicated by a two-dot chain line arrow F ₁₁ in FIG. 6B. However, by providing the additional plate 54, it is possible to guide such cooling air to the exhaust ports 52ba and 52ea. The cooling air can be efficiently discharged with the opening areas of the exhaust ports 52ba and 52ea.

Since high cooling air discharge efficiency is obtained in this way, the same effect as in the first embodiment can be obtained.
In the above description, the additional plate 54 is a component of the engine hood 50 and is fixed to the hood main body 51. However, the additional plate 54 may be fixed to the body main body 21 as shown in FIG. In this case, the engine hood is constituted by the member 51 (the bulging portion 52, the flat plate portion 53, and the partition plate 57) alone, and the engine hood 51 is closed as shown in FIGS. 8, the air passage having the opening 55 formed between the bulging portion 52 and the additional plate 54 facing the engine room 2B as an inlet and the exhaust ports 52ba and 52ea of the engine hood 51 as outlets. 56 is formed.

(3) Others The engine room structure of the construction machine and the cooling device for the construction machine of the present invention are not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.
For example, in the above embodiment, the configuration in which the engine hood functions as a duct is illustrated, but a cooling air exhaust duct may be provided on the upper wall surface forming the engine room separately from the engine hood. Referring to FIG. 3, the opening 44 is formed in the upper wall surface of the machine body, and the member 41 may be fixed to the upper wall surface of the machine body as a duct so as to cover the opening 44 (this configuration is the first embodiment described above). It can also be said that the upper wall surface 22 and the bottom plate 42 in FIG. In this case, the maintenance port and the engine hood may be installed at other parts of the upper wall surface of the machine body.

  Moreover, the engine hood of the construction machine of the present invention can be configured without a bottom plate. For example, the hood 50 of the second embodiment shown in FIG. 7 may have a configuration without the additional plate 54 as the bottom plate. Even in this case, the exhaust port 52ea provided on the downstream side in the fan swirl flow direction is mainly used as the exhaust. Cooling air can be efficiently discharged from the outlets 52ba and 52ea.

It is a typical perspective view showing the whole construction machine composition concerning a 1st embodiment of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the structure of the engine hood of the construction machine, the engine room structure of a construction machine, and the cooling device of a construction machine as 1st Embodiment of this invention, Comprising: (a) is typical cross section seen from the body front FIG. 2B is a schematic AA sectional view of FIG. It is the figure which shows the engine hood of the construction machine concerning 1st Embodiment of this invention partially fractured | ruptured, Comprising: It is the typical perspective view seen from diagonally upward. It is the typical perspective view which looked at the upper revolving super structure principal part of the state which closed the engine hood concerning 1st Embodiment of this invention from diagonally upward. It is the typical perspective view which looked at the upper turning body principal part in the state where the engine hood concerning a 1st embodiment of the present invention was opened from the slanting upper part. It is a figure which shows the structure of the engine hood of the construction machine as 2nd Embodiment of this invention, the engine room structure of a construction machine, and the cooling device of a construction machine, Comprising: (a) is typical cross section seen from the body front FIG. 4B is a schematic BB cross-sectional view of FIG. It is the figure which shows the engine hood of the construction machine concerning 2nd Embodiment of this invention partially broken, Comprising: It is the typical perspective view seen from diagonally upward. It is the typical perspective view which looked at the upper turning body principal part in the state where the engine hood concerning a 2nd embodiment of the present invention was closed from the slanting upper part. It is the typical perspective view which looked at the upper turning body principal part in the state where the engine hood concerning a 2nd embodiment of the present invention was opened from the slanting upper part. It is the typical perspective view which looked at the upper revolving superstructure principal part of the state which opened the engine hood concerning the modification of 2nd Embodiment of this invention from diagonally upward. It is a typical perspective view which shows the whole structure of the conventional construction machine. It is a figure which shows the internal structure of the engine room of the conventional construction machine, Comprising: It is typical sectional drawing of the engine room seen from the body front. It is a figure for demonstrating the relationship between the width in an engine room and the thickness of a cooling package in the cooling device of a construction machine, (a) is a schematic diagram when the inside of an engine room is comparatively narrow, (b) It is a schematic diagram when the inside of an engine room is comparatively wide. It is a schematic diagram which shows the performance curve of the cooling fan of a general axial flow type. (A), (b) is a schematic diagram which shows the flow of the cooling air before and behind a cooling fan by a vector when the upstream pressure loss is comparatively small. (A), (b) is a schematic diagram which shows the flow of the cooling air before and behind a cooling fan by a vector when the upstream pressure loss is comparatively large. It is a typical perspective view which shows the structure of the cooling device of the conventional construction machine.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Lower traveling body 2 Upper turning body 2A Counterweight 2B Engine room 2Ba Radiator room 2Bb Main engine room 2Bc Pump room 3 Working device 21 Machine body 22 Machine body upper wall surface 23 Machine body lower wall surface 22a Maintenance port 22c Engine room introduction opening 24 Cooling Package 25 Cooling fan 26 Engine 26a Muffler 27 Engine pump 40, 50 Engine hood 41 Expansion plate 41a Expansion plate main surface 41b End surface 41e of the expansion plate on the downstream side of the fan axial flow direction Fan swirl flow direction of the expansion plate Downstream end faces 41ba, 41ea Discharge opening 42 formed in the bulging plate Additional plate (bottom plate)
43 Air passage 44 formed in the engine hood 44 Communication port 51 Hood body 52 Swelling part (swelling plate)
52b End face 52e on the downstream side in the fan axial flow direction of the bulging plate End face 52ba, 52ea on the downstream side in the swirling flow direction of the bulging plate Discharge opening 53 formed in the bulging portion Flat plate portion 54 Additional plate (bottom plate)
55 Communication port 56 Air path formed in the engine hood

Claims (15)

An engine hood for a construction machine that opens and closes a maintenance port formed on an upper wall surface of an engine room that houses an engine, a cooling fan, and a cooling package installed on the upstream side in the axial direction of the cooling fan,
In the closed position of closing the maintenance port, the shape is formed so as to bulge upward with respect to the upper wall surface, and the cooling air flows to the downstream portion in the axial direction and the downstream portion in the swirling direction of the cooling fan, respectively. An engine hood for a construction machine, characterized by comprising a bulging plate in which a discharge port is formed. A bottom plate assembled to the bulging plate below the discharge port so as to open a space with respect to the upper portion of the bulging plate;
2. The engine hood for a construction machine according to claim 1, comprising a space between the bulging plate and the bottom plate and a communication port for communicating the engine room. The engine hood for a construction machine according to claim 2, wherein the communication port is disposed above the cooling fan. The bottom plate is assembled to the bulging plate with a gap on the upstream side in the fan axial flow direction with respect to the inner wall surface of the bulging plate, and the communication port is formed by the gap. Item 4. The engine hood for a construction machine according to Item 2 or 3. The bottom plate is assembled to the bulging plate with a gap on the upstream side in the fan swirl flow direction with respect to the inner wall surface of the bulging plate, and the communication port is formed by the gap. Item 4. The engine hood for a construction machine according to Item 2 or 3. The construction machine according to any one of claims 1 to 5, wherein a wall surface on the upstream side in the swirling flow direction of the bulging plate is formed in a curved shape along the swirling flow direction. Engine hood. An engine room structure for a construction machine that houses an engine, a cooling fan, and a cooling package installed on the upstream side in the axial direction of the cooling fan,
A maintenance port is formed on the upper wall surface forming the engine room, and the engine hood of the construction machine according to any one of claims 1 to 6 is attached to the upper wall surface with respect to the maintenance port. And engine room structure of construction machinery. An engine room structure for a construction machine that houses an engine, a cooling fan, and a cooling package installed on the upstream side in the axial direction of the cooling fan,
A maintenance port is formed on the upper wall surface of the machine body forming the engine room, and the engine hood of the construction machine according to claim 1 is attached to the maintenance port,
The engine hood is attached to the fuselage main body and is connected to the bulging plate below the discharge port so as to open a space with respect to the upper portion of the bulging plate in a closed position with the maintenance port closed. A bottom plate,
An engine room structure for a construction machine, characterized by comprising a space between the bulging plate and the bottom plate and a communication port for communicating with the engine room. The engine room structure for a construction machine according to claim 7 or 8, wherein a wall surface of the bulging plate on the upstream side in the swirl flow direction is formed in a curved shape along the swirl flow direction. An engine room structure for a construction machine that houses an engine, a cooling fan, and a cooling package installed upstream in the axial direction of the cooling fan, and whose internal space functions as a cooling air passage,
An opening formed in the upper wall surface forming the engine room;
A duct which is attached to the outside of the upper wall surface so as to cover the opening, and has a cooling air discharge port at a downstream portion in the axial flow direction and a downstream portion in the swirling flow direction of the cooling fan; The engine room structure of construction machinery, characterized by comprising The engine room structure for a construction machine according to claim 10, wherein the opening is disposed above the cooling fan. The engine room structure for a construction machine according to claim 10 or 11, wherein a wall surface upstream of the duct in the swirling flow direction is formed in a curved shape along the swirling flow direction. A cooling device for a construction machine, comprising a cooling air passage formed by an internal space of an engine room, a cooling fan, and a cooling package installed upstream in the axial direction of the cooling fan,
An opening formed in the upper wall surface forming the engine room;
A duct which is attached to the outside of the upper wall surface so as to cover the opening, and has a cooling air discharge port at a downstream portion in the axial flow direction and a downstream portion in the swirling flow direction of the cooling fan; A construction machine cooling device, characterized by comprising: 14. The cooling device for a construction machine according to claim 13, wherein the opening is disposed above the cooling fan. The cooling device for a construction machine according to claim 13 or 14, wherein a wall surface upstream of the duct in the swirling flow direction is formed in a curved shape along the swirling flow direction.

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