JPH11254976A - Noise reducing device for construction machine and cover and exhaust part used for this device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the exhaust noises of a construction machine by providing, on the upper surface of a cover, an exhaust part for exhausting air to the outside while allowing an air flow flowing out with a prescribed angle to the axial line of the rotating shaft of a fan. SOLUTION: A side cover 22 and an opening and closing cover 23 constitute a cover for covering an engine, a cooling fan and the like. An exhaust part 31 is provided on the upper surface of the opening and closing cover 23 to guide and discharge the air flow flowing out of the cooling fan to the outside. An exhaust air guide body mounting frame and a plurality of exhaust air guide bodies 35 are provided on the substantially rectangular opening on the opening and closing cover 23. The exhaust air guide bodies 35 are arranged so as to substantially orthogonal to the air flow flowing out with a prescribed angle to the axial line of an auxiliary rotating shaft which is the rotating shaft of the cooling fan. Since exhaust can be actively performed while guiding such an air flow to diagonal direction, the air flow can be discharged to the outside with a small air resistance. Consequently, the exhaust noises can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a noise reduction device for a construction machine, and more particularly, to a noise reduction device for a construction machine capable of reducing noise based on exhaust air from a fan for cooling a radiator, an oil cooler, or the like. Things.

[0002]

2. Description of the Related Art An engine mounted on a rear part of a revolving superstructure of a construction machine and an auxiliary machine related to the engine are usually covered with an engine cover. The engine cover of this type of construction machine, after passing the air taken in from the intake hole provided on one side to a heat exchanger such as a radiator or an oil cooler by a cooling fan, further passes the side of the engine, Since the air is exhausted to the outside through the exhaust hole provided on the other side of the engine cover, the distance from the above-described intake hole to the exhaust hole is long, and the air passage resistance is large.
In order to solve this point, as described in JP-A-9-156384, an opening is provided on the upper surface of the engine cover, and one end of an exhaust duct is fixed to this opening,
A configuration has been proposed in which the other end of the exhaust duct is located behind the cooling fan, and the rear of the engine is closed by a partition.

[0003]

In the above prior art, the air passing through a radiator is discharged to the outside through an exhaust duct immediately after a cooling fan, and the passage distance from the intake to the exhaust is shortened. Is to reduce the passage resistance of the wire. Here, generally, an axial fan is used as a cooling fan in a construction machine. This axial fan normally generates airflow from the upstream side to the downstream side in the axial direction of the fan when there is no airflow resistance on the upstream side or the downstream side. However, in a construction machine, a radiator or the like having a large passage resistance is disposed on the upstream side of the axial fan and an engine is disposed on the downstream side. It becomes a passing resistor. As a result, the air that has passed through the axial fan is swirled by the rotation of the blades of the axial fan, and flows in a diagonal direction that has not only an axial component but also a centrifugal component. The fluid flows out at an angle in the fan rotation direction with respect to the axial direction of the fan rotation shaft. However, the above-mentioned prior art does not sufficiently consider the outflow angle of the airflow, and the exhaust duct is arranged parallel to the axis of the crankshaft of the engine when viewed from the upper surface thereof. Therefore, the air that has passed through the fan described above flows into the exhaust duct at an angle. As a result, there is a regret that the passage resistance in the exhaust duct becomes large, and the collision noise and the wind noise of the exhaust in the exhaust duct are generated, and these noises are loud.
The generation of such noise is not preferable from the viewpoint of environmental protection in recent years.

Further, in the above-mentioned conventional technology, all of the air passing through the radiator does not flow into the exhaust duct, and part of the air flows rearward from the side of the engine. At this time, since the rear of the engine is closed by the partition wall, the flow flowing in behind the engine is captured in the engine room. as a result,
There is a regret that the temperature rise in the engine room cannot be sufficiently suppressed.

A first object of the present invention is to provide a noise reduction device for a construction machine capable of reducing the exhaust noise of the construction machine, and a cover and an exhaust portion used for the device.

A second object of the present invention is to provide a noise reduction device for a construction machine capable of sufficiently suppressing a temperature rise in an engine room of the construction machine, and a cover and an exhaust portion used for the device.

[0007]

According to the present invention, in order to achieve the first object, a heat exchanger such as a radiator or an oil cooler and an engine are cooled by an air flow generated by a fan. In a construction machine in which a heat exchanger and a fan are covered with a cover, an exhaust unit is provided on an upper surface of the cover to allow an airflow flowing out at an angle θ with respect to an axis of a rotation axis of the fan and discharge the air to the outside. A noise reduction device for a construction machine. When heat exchangers such as radiators and oil coolers and engines are cooled by the airflow of fans in construction machinery, these heat exchangers and engines are arranged at relatively close positions on the upstream or downstream side of the fans. These are the
An outflow obstruction, that is, an air passage resistor. As a result, the air that has passed through the fan is drawn by the rotation of the blades of the fan, and flows in a diagonal flow direction with a component in the axial direction and a component in the centrifugal direction. Flows out at an angle θ in the fan rotation direction. In the present invention, an exhaust portion is provided in a cover that covers the engine, the heat exchanger, and the fan, and the air is discharged to the outside while allowing such an air flow. That is, for example, it is discharged to the outside while being guided by a plurality of exhaust guides, is discharged to the outside while allowing through a plurality of openings, or is discharged to the outside while being guided by openings. Thus, the exhaust resistance can be reduced, so that the exhaust noise can be reduced.

Further, in a construction machine in which a heat exchanger such as a radiator or an oil cooler and an engine are cooled by an air flow generated by a fan, and the engine, the heat exchanger and the fan are covered with a cover, an upper surface of the cover is provided. A noise reduction device for a construction machine, further comprising an exhaust portion provided with a plurality of exhaust guides for guiding an air flow flowing out at an angle θ with respect to the axis of the rotation shaft of the fan and discharging the air flow to the outside. It is in.

Further, in a construction machine in which a heat exchanger such as a radiator and an oil cooler and an engine are cooled by an air flow generated by a fan, and the engine, the heat exchanger and the fan are covered with a cover, the upper surface of the cover is provided. A noise reduction device for a construction machine, further comprising: an exhaust portion having a plurality of openings for discharging air to the outside while allowing an airflow flowing at an angle θ with respect to the axis of the rotation axis of the fan. .

In a construction machine in which a heat exchanger such as a radiator or an oil cooler and an engine are cooled by an air flow generated by a fan, and the engine, the heat exchanger and the fan are covered with a cover, the upper surface of the cover is provided. A noise reduction device for a construction machine, further comprising an exhaust portion provided with an opening for guiding an air flow flowing out at an angle θ with respect to an axis of a rotation shaft of the fan and discharging the air flow to the outside.

Further, in a construction machine in which a heat exchanger such as a radiator or an oil cooler and an engine are cooled by an air flow generated by a fan and the engine, the heat exchanger and the fan are covered with a cover, the upper surface of the cover is provided. A noise reduction device for a construction machine, further comprising an exhaust portion having a centrifugal component and an axial component and allowing air to flow out of the fan in a diagonal direction and discharging the air to the outside.

[0012] Preferably, in the noise reduction device for a construction machine, the exhaust portion discharges an airflow that flows out at an angle θ in a rotation direction of the fan with respect to an axis of a rotation shaft of the fan.

Preferably, in the noise reduction device for a construction machine, the fan is configured such that a rotating shaft arranged substantially parallel to a crankshaft of the engine is driven by the power of the crankshaft. The exhaust portion discharges air to the outside while allowing an airflow flowing at an angle θ with respect to the axis of the crankshaft.

More preferably, in the noise reduction device for a construction machine, the fan is an axial fan. Axial fans are often used as cooling fans in construction machinery.Usually, axial fans are used from upstream to downstream when there is no passage resistance on the upstream or downstream side. An air flow is generated in the axial direction of the fan. Therefore, the exhaust hole provided in the cover of the construction machine may be provided mainly only at a position corresponding to the airflow in the axial direction. In such a case, it is not possible to cope with the actual airflow flowing out at an angle θ with respect to the axial direction of the rotation axis of the fan, and the air passage resistance becomes particularly large due to the long distance from the intake hole to the exhaust hole. Therefore, the effect of reducing the air passage resistance can be obtained by the configuration of the present invention.

Preferably, in order to achieve the first and second objects, in the noise reduction device for a construction machine, a part of the cover other than the exhaust portion is provided with a part of an air flow flowing out of the fan. An exhaust hole for exhausting the part to the outside is provided. Most of the airflow flowing out of the fan flows out at an angle θ with respect to the axial direction of the rotation axis of the fan,
Although exhausted from the exhaust portion, a part of the airflow does not flow into the exhaust portion, but passes rearward, for example, by passing a side of the engine. Therefore, by providing an exhaust hole in a portion other than the exhaust portion of the cover, the exhaust hole can be exhausted to the outside.
As a result, unlike the conventional structure in which the rear of the engine is closed by the partition, the airflow also flows out from the rear of the engine, so that the temperature rise in the engine room can be sufficiently suppressed.

According to the present invention, in order to achieve the first object, a heat exchanger such as a radiator or an oil cooler and an engine are cooled by an air flow generated by a fan, and the engine, the heat exchanger, In a construction machine in which a fan is covered with a cover, an exhaust unit is provided on an upper surface of the cover to allow an airflow flowing out at an angle θ with respect to an axis of a rotation axis of the fan and discharge the air to the outside. In the cover for noise reduction of construction machinery.

Further, according to the present invention, in order to achieve the first object, a heat exchanger such as a radiator or an oil cooler and an engine are cooled by an air flow generated by a fan, and the engine, the heat exchanger, In a construction machine in which a fan is covered with a cover, a plurality of exhaust guides are provided on an upper surface of the cover and guide the airflow that flows out at an angle θ with respect to the axis of the rotation axis of the fan and discharge the airflow to the outside. An exhaust part for reducing noise of construction machinery.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a hydraulic shovel will be described below with reference to the drawings. First, an embodiment of the present invention will be described with reference to FIGS.

FIG. 1 shows a hydraulic excavator to which the present invention is applied. In FIG. 1, reference numeral 1 denotes a traveling body, 2 denotes a revolving body provided so as to be revolvable on the traveling body 1, and 3 denotes a revolving body. A driver's cab provided on the left front side, 4 is an engine device disposed horizontally on the revolving unit 2, 5 is a counterweight provided on a rear portion of the revolving unit 2, and 6 is provided on a front portion of the revolving unit 2. , A boom 6a, an arm 6b, and a bucket 6c.

The traveling body 1 is provided with a crawler track 1 on the left and right.
a. The crawler track 1a is driven by a driving force of a traveling motor 1b. The revolving superstructure 2 including the cab 3, the engine device 4, the counterweight 5, and the articulated front device 6, etc.
Is turned with respect to the traveling body 1 by a turning motor (not shown) provided at the center of the vehicle. The boom 6a, the arm 6b, and the bucket 6c constituting the articulated front device 6 have cylinders 7 attached thereto.
Drive operation is performed by a, 7b, and 7c. The above-described cylinders 7a, 7b, 7c, a turning motor, and a traveling motor 1
A drive device (actuator) such as b is an oil pump driven by an engine 8 (described later) in response to the operation of an operation lever operated by an operator in the cab 3 as in a known hydraulic drive device. 18 (described later) is driven by pressure oil from a control valve device (not shown) for controlling pressure oil.

FIG. 2 is an enlarged perspective view showing an external structure of an engine device 4 provided with an embodiment of the noise reduction device of the present invention, and FIG. 3 is provided with an embodiment of the noise reduction device of the present invention. III-III in FIG.
FIG. 4 is a longitudinal sectional view in cross section. In FIGS. 2 and 3, the same reference numerals as those in FIG. 1 indicate the same parts.

In FIGS. 2 and 3, reference numeral 8 denotes a vibration damping device 1 on a main frame 9, which forms a foundation lower structure of the rotating body 2.
Reference numeral 11 denotes a crankshaft of the engine 8, reference numeral 12 denotes an auxiliary rotary shaft connected to the crankshaft 11 via a belt 13, and reference numeral 14 denotes a cooling fan provided on the auxiliary rotary shaft 12. An axial fan is used for the fan 14 as in the case of an engine device of a general construction machine of this type. A water pump (not shown) that circulates engine cooling water to a radiator, which will be described later, is connected to the other of the above-described auxiliary rotation shaft 12. 15 is the cooling fan 14
This heat exchanger 15 cools oil supplied to the actuator from a radiator to which cooling water for the engine 8 is circulated and supplied from an oil pump 18 (described later). It is composed of an oil cooler, an intercooler installed for pre-cooling combustion air to the engine 8 if necessary, and a condenser of an air conditioner. Reference numeral 16 denotes a partition member for closing the upper part of the heat exchanger 15, reference numeral 17 denotes a shroud fixed downstream of the heat exchanger 15, reference numeral 18 denotes an oil pump connected to the engine 8 and driven by its driving force, and reference numeral 19 denotes an engine 8 A muffler for guiding the exhaust gas to muffle the exhaust gas, 20 is an exhaust gas pipe of the muffler 19, 21
Is a muffler cover fixed to the upper part of the engine. The muffler cover 21 prevents oil from scattering from the oil pump 18 to the engine 8 side.

A side cover 22 provided on the revolving unit 2;
Reference numeral 23 denotes a maintenance opening / closing cover provided on the side cover 22 so as to be openable and closable. The side cover 22 and the opening / closing cover 23 are used for the engine 8, the cooling fan 14, the heat exchanger 15, the oil pump 18, the muffler 19 and the like. It constitutes a cover for covering. As shown in FIG.
As shown in FIG. 2, a hinge 24 connects the side cover 22 to the side cover 22, and the other end of the open / close cover 23 is provided with a lock 25 for hooking the open / close side to the side cover 22. On the heat exchanger 15 side of the side cover 22 and the opening / closing cover 23 described above, suction holes 26 and 27 are provided, respectively, and on the side of the oil pump 18 of the side cover 22 and the opening / closing cover 23, the air flows out of the cooling fan 14. Exhaust holes 28 and 29 are provided for exhausting portions of the airflow other than those exhausted from an exhaust portion 31 (described later) to the outside.
Reference numeral 30 denotes an exhaust gas pipe through hole provided on the upper surface of the opening / closing cover 23.

Reference numeral 31 denotes an exhaust unit for guiding the air flow flowing out of the cooling fan 14 and discharging the air to the outside. FIG. 4 shows a detailed structure of the exhaust portion 31 in FIG.
5 is a cross-sectional view taken along line VV in FIG. 4 showing a detailed structure of the exhaust unit 31. These figures 4
As shown in FIG. 5, the exhaust portion 31 is provided on the upper surface of the opening / closing cover 23 corresponding to between the rear end of the cooling fan 14 and the front portion of the engine 8, and is formed on the opening / closing cover 23. A substantially rectangular opening 32, a fixing flange 33 attached to the opening 32, an exhaust guide mounting frame 34 integrally formed with the fixing flange 33, and an attachment to the exhaust guide mounting frame 34. And a plurality of exhaust guides 35. The fixing flange 33 described above is fixed by being joined to the opening / closing cover 23 by means such as welding or bolts.

As shown in FIG. 4, the exhaust guide 35 has an angle θ with respect to the axis X of the auxiliary rotation shaft 12 (which also corresponds to the axis of the crankshaft 11 of the engine 8) which is the rotation axis of the cooling fan 14. And is arranged substantially orthogonal to the air flow E (described later in detail) flowing out. Although the exhaust guide 35 is a substantially plate-shaped member as shown in FIGS. 4 and 5, the exhaust guide 35 is made of a relatively lightweight material, so that even if the exhaust guide 35 is exposed to relatively large vibrations during the operation. Damage is prevented.

Next, the operation of one embodiment of the above-described noise reduction device of the present invention will be described. When the engine 8 is driven, the rotation of the crankshaft 11 of the engine 8 is transmitted to the auxiliary rotation shaft 12 via the belt 13 as shown in FIG. 3, and the auxiliary rotation shaft 12 rotates. The rotation of the auxiliary rotation shaft 12 causes the cooling fan 14 to rotate. This cooling fan 14
By the rotation of, air is sucked from the intake holes 26 and 27 to cool the heat exchanger 15. Then, the air that has passed through the heat exchanger 15 flows into the cooling fan 14.

Here, the cooling fan 14 is an axial fan as described above. Generally, when there is nothing behind the fan that causes air passage resistance before and after the fan, when the fan is rotated at a normal rotation speed (for example, a rated rotation speed), the air flows parallel to the axis of the fan rotation shaft. It is flowing. However, in the present embodiment, as described above, the heat exchanger 15 and the like are provided upstream of the cooling fan 14 and the engine 8 is provided downstream thereof.
Are relatively close to each other, and these serve as obstacles for air inflow and outflow, that is, air passage resistors.
As a result, most of the air flowing out of the cooling fan 14 is dragged by the rotation of the fan blades in a counterclockwise direction (see the arrow in FIG. 3) as viewed from the engine 8 side, and the axial component and centrifugal force are generated. The present invention is based on the finding that the airflow E in the diagonal flow direction having a component in the direction flows out at an angle θ in the fan rotation direction with respect to the axis X of the auxiliary rotation shaft 12 which is the rotation axis of the cooling fan 14. People got it. The present inventors have also confirmed that the angle at this time is about θ = 30 ° to 45 ° at an engine speed (for example, about 2000 rpm) corresponding to the excavation operation of a normal hydraulic excavator. In the present embodiment, as described above,
In the exhaust part 31, the exhaust guide 35 is disposed so as to be substantially orthogonal to the direction of the air flow E, so that the air flow E in such a diagonal flow direction can be actively discharged while being guided. Therefore, this air flow can be discharged to the outside with a small exhaust resistance. As a result, exhaust noise can be reduced. In addition, since an extra load is not applied to the cooling fan 14, the cooling effect of devices such as the heat exchanger 15 and the engine 8 can be improved. further,
As a result, the same cooling effect can be ensured even if the rotation speed of the cooling fan 14 is reduced or the diameter of the cooling fan 14 is reduced, so that the rotation noise of the cooling fan 14 can be reduced.

On the other hand, a part of the air flowing out of the cooling fan 14 is used as an air flow F other than the air flow E as the exhaust unit 31.
The engine 8 and the oil pump 18 and the like are cooled without going to the outlet, and are discharged from the exhaust holes 28 and 29 to the outside. In this way, by providing the exhaust holes 28 and 29 in addition to the exhaust portion 31, unlike the conventional structure in which the rear of the engine is closed by the partition wall, the airflow F can be discharged to the outside also from the rear of the engine. Side cover 22, openable cover 2
The temperature rise in the space (the so-called engine room) inside 3 can be sufficiently suppressed.

FIG. 6 is a perspective view showing an external structure of an engine device 4 provided with another embodiment of the noise reduction device of the present invention, and FIG. 7 is a view showing another embodiment of the noise reduction device of the present invention. FIG. 8 is a top view showing the structure of the exhaust unit provided, and FIG.
FIGS. 2A and 2B are cross-sectional views taken along the line II-VIII, in which the same reference numerals as those shown in FIGS. 1 to 5 indicate the same or corresponding parts. In the exhaust part 31 of this embodiment, as shown in FIGS. 6 and 7, a substantially rectangular opening 32 has a short side with respect to the axis X of the auxiliary rotation shaft 12 (the axis of the crankshaft 11 of the engine 8) X. Is formed so as to form an angle θ in the fan rotation direction.
A plurality of exhaust guides 35 are juxtaposed along the longitudinal direction of the fixing flange 33 and the exhaust guide mounting frame 34 attached to the second unit 2. Thus, similarly to the embodiment of FIGS. 1 to 5, the exhaust guide 35 is substantially orthogonal to the airflow E flowing out at an angle θ with respect to the axis X of the auxiliary rotation shaft 12 which is the rotation shaft of the cooling fan 14. It has become.

According to this embodiment, since the exhaust resistance of the air flowing out at an angle θ can be reduced as in the above-described embodiment of the present invention, the effect of reducing the exhaust noise can be obtained. Further, as compared with the embodiment of the present invention, all of the plurality of exhaust guides 35 can have the same shape and the number of installed exhaust guides can be reduced, so that cost can be reduced and exhaust guide mounting can be achieved. There is also an effect that the attachment work to the frame 34 is simple.

In the above-described embodiment of the present invention,
An opening 32 provided on the upper surface of the opening / closing cover 23 is provided with a fixing flange 3.
3 and an exhaust guide mounting frame 34, and a plurality of exhaust guides 35
And the exhaust part 31 is configured, but is not limited to this. That is, the opening / closing cover 23 is usually formed by press molding from a single plate, but when the opening / closing cover 23 is press-formed, portions corresponding to the fixing flange 33 and the exhaust guide mounting frame 34 are integrally formed. A plurality of exhaust guides 35 may be attached to this portion. In this case, the manufacturing time and cost of the exhaust unit 31 can be reduced.

FIG. 9 is a perspective view of an engine device 4 having still another embodiment of the noise reduction device of the present invention. In FIG. 9, the same reference numerals as those shown in FIGS. Those indicate the same or corresponding parts. The exhaust part 31 in this embodiment is provided with an opening / closing cover 2 corresponding to a space between the rear end of the cooling fan 14 and the front part of the engine 8.
An opening 36 that allows an airflow E flowing out at an angle θ in the fan rotation direction with respect to the axis X of the auxiliary rotation shaft 12 (the axis of the crankshaft 11 of the engine 8) X which is the rotation axis of the cooling fan 14. Are provided in plurality. That is, the direction of the axis (= the direction of the long side) of the opening 36 having a relatively small and substantially rectangular shape is formed so as to form an angle θ in the fan rotation direction with respect to the axis X. Here, the opening / closing cover 23 is usually formed from a single plate by press molding, but the plurality of openings 36 can be formed simultaneously during the press molding.

According to this embodiment, since the exhaust resistance of the air flowing out at an angle θ can be reduced as in the above-described embodiment of the present invention, the effect of reducing the exhaust noise can be obtained. Further, in the above-described embodiment of the present invention, components such as the exhaust guide 35 and the exhaust guide mounting frame 34 are newly required for the installation of the exhaust unit 31, and the number of components is increased. In this embodiment, the exhaust unit 3 can be used without increasing the number of parts.
1 can be configured.

In this embodiment, the opening 3
The direction of the long side of the rectangle 6 is set to the direction that forms an angle θ in the fan rotation direction with respect to the axis X, but is not limited thereto.
May be provided in parallel. In this case as well, for example, by providing a sufficiently large number of sufficiently small openings 36 as shown in FIG. 9, the airflow E flowing out at an angle θ in the fan rotation direction with respect to the axis X can be allowed. In this embodiment, the opening 36 is provided over substantially the entire lateral direction of the upper surface of the opening / closing cover 23 (the front-rear direction of the excavator; see FIG. 9).
That is, it may be provided only in half of the counter weight 5 side. If an opening cannot be provided in a half of the counterweight 5 side, the opening may be provided on the upper side of the opening / closing cover 23 on the side of the cab 3.

FIGS. 10 and 11 are a longitudinal sectional view showing the internal structure of an engine device 4 having another embodiment of the noise reduction device of the present invention, and a top view taken along line XI-XI in FIG.
10 and 11, the same reference numerals as those shown in FIG. 3 indicate the same or corresponding parts. As shown in FIG. 10, the exhaust part 31 in this embodiment includes an opening 37 provided on the upper surface of the opening / closing cover 23 and the other end having the other end facing the upper part behind the cooling fan 14.
And an exhaust duct 38 fixed to the exhaust duct 38. As shown in FIG. 11, the opening 37 has a substantially parallelogram shape when viewed from above, and the short side faces the axis of the auxiliary rotation shaft 12 (the crank of the engine 8) which is the rotation axis of the cooling fan 14. The axis θ of the axis 11) in the direction of rotation of the fan with respect to X
, And the arrangement position thereof is also shifted from the axis X to the counterweight 5 side on the upper surface of the opening / closing cover 23. Accordingly, the exhaust duct 38 is also arranged such that its axis forms an angle θ with respect to the axis X in the fan rotation direction. As a result, each of the exhaust duct 38 and the opening 37 guides the airflow E flowing out at an angle θ in the fan rotation direction with respect to the axis X and discharges the airflow E to the outside.

According to this embodiment, since the exhaust resistance of the air flowing out at an angle θ can be reduced as in the above-described embodiment of the present invention, the effect of reducing the exhaust noise can be obtained. Also, one large opening 37
Therefore, the manufacturability of the exhaust part 31 can be significantly improved.

In the above embodiment, an example in which the open / close cover 23 is provided on the side cover 22 has been described. However, the present invention is also applicable to a cover structure in which the open / close cover 23 is integrated with the fixed cover. Can be.

[0038]

According to the present invention, the flow of the air flowing out at an angle θ generated by the fan, that is, the flow in the diagonal direction is discharged to the outside by reducing the exhaust resistance by the exhaust portion provided on the upper surface of the cover. Therefore, the noise can be reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an external appearance of a hydraulic shovel to which the present invention is applied.

FIG. 2 is an enlarged perspective view illustrating an external structure of an engine device including the noise reduction device according to an embodiment of the present invention.

FIG. 3 shows an internal structure of an engine device provided with one embodiment of the noise reduction device of the present invention shown in FIG. 2;
It is a longitudinal cross-sectional view by II cross section.

FIG. 4 is a top view taken along the line IV-IV in FIG. 3 showing a detailed structure of an exhaust part constituting the noise reduction device of the present invention shown in FIG. 3;

FIG. 5 is a cross-sectional view taken along a line VV in FIG. 4 showing a detailed structure of an exhaust part constituting the noise reduction device of the present invention shown in FIG.

FIG. 6 is a perspective view illustrating an external structure of an engine device provided with another embodiment of the noise reduction device of the present invention.

FIG. 7 is a top view illustrating a detailed structure of an exhaust unit included in the noise reduction device of the present invention illustrated in FIG.

8 is a cross-sectional view taken along the line VIII-VIII in FIG. 7, showing a detailed structure of an exhaust part constituting the noise reduction device of the present invention shown in FIG.

FIG. 9 is a perspective view illustrating an external structure of an engine device including a noise reduction device according to still another embodiment of the present invention.

FIG. 10 is a longitudinal sectional view showing an internal structure of an engine device provided with another embodiment of the noise reduction device of the present invention.

FIG. 11 is a cross-sectional view XI of FIG. 10 showing a structure in the vicinity of an exhaust part which constitutes another embodiment of the noise reduction device of the present invention shown in FIG.
It is a XI arrow top view.

[Explanation of symbols]

15 heat exchanger, 8 engine, 11 crankshaft, 1
2 ... Auxiliary rotating shaft (rotating shaft of fan), 14 ... Cooling fan (fan), 22 ... Fixed cover (cover), 23 ... Open / close cover (cover), 28 ... Exhaust hole, 29 ... Exhaust hole, 31
... exhaust part, 32 ... opening, 33 ... fixing flange, 34 ... exhaust guide mounting frame, 35 ... exhaust guide, 36 ... opening (a plurality of openings), 37 ... opening, 38 ... exhaust duct.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI F01P 11/10 F01P 11/12 J 11/12 B62D 25/10 L Inside the Tsuchiura Plant of Hitachi Construction Machinery Co., Ltd.

Claims (11)

[Claims] 1. A construction machine in which a heat exchanger such as a radiator or an oil cooler and an engine are cooled by an airflow generated by a fan, and the engine, the heat exchanger and the fan are covered with a cover. A noise reduction device for a construction machine, further comprising an exhaust portion that allows an air flow flowing out at an angle θ with respect to an axis of a rotation shaft of the fan and discharges the air to the outside. 2. A construction machine in which a heat exchanger such as a radiator or an oil cooler and an engine are cooled by an air flow generated by a fan and the engine, the heat exchanger and the fan are covered with a cover. A noise reduction device for a construction machine, further comprising an exhaust portion provided with a plurality of exhaust guides for guiding an air flow flowing out at an angle θ with respect to the axis of the rotation shaft of the fan and discharging the air flow to the outside. . 3. A construction machine in which a heat exchanger such as a radiator or an oil cooler and an engine are cooled by an air flow generated by a fan, and the engine, the heat exchanger and the fan are covered with a cover. A noise reduction device for a construction machine, further comprising: an exhaust portion having a plurality of openings for discharging air to the outside while allowing an air flow flowing at an angle θ with respect to an axis of a rotation shaft of the fan. 4. A construction machine in which a heat exchanger such as a radiator or an oil cooler and an engine are cooled by an air flow generated by a fan, and the engine, the heat exchanger, and the fan are covered with a cover. A noise reduction device for a construction machine, further comprising an exhaust portion provided with an opening for guiding an air flow flowing out at an angle θ with respect to an axis of a rotation shaft of the fan and discharging the air flow to the outside. 5. A construction machine in which a heat exchanger such as a radiator or an oil cooler and an engine are cooled by an air flow generated by a fan and the engine, the heat exchanger and the fan are covered with a cover. A noise reduction device for a construction machine, further comprising: an exhaust portion having a centrifugal component and an axial component and allowing the airflow flowing out of the fan in the diagonal flow direction to be discharged to the outside. 6. The noise reduction device for a construction machine according to claim 1, wherein said exhaust portion flows out at an angle θ in a rotation direction of said fan with respect to an axis of a rotation shaft of said fan. A noise reduction device for a construction machine, which discharges an air flow to the outside. 7. The noise reduction device for a construction machine according to claim 1, wherein said fan comprises a rotary shaft disposed substantially parallel to a crankshaft of said engine, and wherein a power of said crankshaft is reduced. Is configured to be driven by
In addition, the exhaust unit allows the airflow that flows out at an angle θ with respect to the axis of the crankshaft and discharges the airflow to the outside while permitting the airflow. 8. The noise reduction device for a construction machine according to claim 1, wherein said fan is an axial fan. 9. The noise reduction device for a construction machine according to claim 1, wherein a part of the airflow flowing out of said fan is discharged to a portion other than said exhaust portion of said cover. A noise reduction device for a construction machine, comprising: 10. A construction machine in which a heat exchanger such as a radiator or an oil cooler and an engine are cooled by an air flow generated by a fan and the engine, the heat exchanger and the fan are covered with a cover. A cover for reducing noise of a construction machine, wherein an exhaust portion is provided to allow an air flow flowing out at an angle θ with respect to an axis of a rotation shaft of the fan and discharge the air to the outside. 11. A construction machine in which a heat exchanger such as a radiator or an oil cooler and an engine are cooled by an air flow generated by a fan and the engine, the heat exchanger and the fan are covered with a cover. And a plurality of exhaust guides for guiding an airflow flowing out at an angle θ with respect to the axis of the rotation axis of the fan and discharging the airflow to the outside.