JP2000120438A - Construction machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To well improve rear visibility, and enhance workability by removing pipelines out of the upper side of a first heat exchanger. SOLUTION: It is so constituted that an inflow pipeline 28 connected with an inter-cooler 24 is run in a place higher than the upper surface 19c of a counter weight 19 through the rear sides in the width direction of a radiator 20 and an oil cooler 21, and an outflow pipeline 29 is also run in a place higher than the upper cover 13 of a building cover 11 through the forward sides in the width direction of the radiator 20 and the oil cooler 21. By this constitution, the inflow pipeline 28 and the outflow pipeline 29 can be removed from the upper sides of the radiator 20 and the oil cooler 21 without setting back the counter weight 19, so that rear visibility from a cab is thereby well improved, and workability and safety can also be enhanced with the height of an engine cover 14 kept low.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a construction machine provided with a heat exchanger such as a radiator, an oil cooler, and an intercooler.

[0002]

2. Description of the Related Art In general, a swing type construction machine such as a hydraulic excavator is known as a construction machine. This hydraulic excavator is composed of a lower traveling body and an upper revolving body rotatably provided on the lower traveling body. And

[0003] Further, the upper revolving superstructure includes a revolving frame provided with a working device on the front side, a building cover provided on the revolving frame, and a left side rear side of the revolving frame positioned in the building cover. An engine mounted in a horizontal position extending rightward, and a counterweight attached to a rear end of the revolving frame for balancing with the working device, one of left and right directions of the engine A heat exchanger is disposed on the side (for example, Japanese Utility Model Laid-Open No. 2-903).
No. 21).

The building cover is composed of left and right side covers and a top cover that define a machine room on a revolving frame. The top cover is used for maintenance work of an engine, a heat exchanger, and the like. Openings are provided.
An engine cover that opens and closes the opening is attached to the top cover.

Further, the heat exchanger includes a radiator which is located near the engine and cools cooling water from the engine, an undercarriage, and an oil cooler which cools hydraulic oil for operating a working device. The first heat exchanger and the first heat exchanger.
And a second heat exchanger such as an intercooler that cools compressed air from a supercharger provided in the engine and that is located on the opposite side of the heat exchanger with respect to the engine in the thickness direction of the first heat exchanger. There are two heat exchangers.

Here, in recent hydraulic excavators, the radiator and the oil cooler are increased in size in order to increase the cooling efficiency of the radiator and the oil cooler, and the upper revolving structure is reduced in size in order to improve the working performance. Therefore, the upper portions of the radiator and the oil cooler protrude from the upper cover of the building cover and are housed in the engine cover.

[0007] Compressed air from a supercharger is supplied to the intercooler via an air pipe, and the compressed air cooled by the intercooler is circulated through another air pipe to an intake manifold of the engine. Since these air pipes have a radiator, an oil cooler and the like interposed between the intercooler and the engine, they are connected to the intercooler so as to get over the radiator and the oil cooler.

[0008]

By the way, in the above-mentioned prior art, each air pipe connecting the intercooler and the engine is routed over the radiator and the oil cooler, so that the air pipe is further above the radiator and the oil cooler. The air pipe protrudes from the
The height dimension of the entire heat exchange device becomes large.

For this reason, the engine cover for covering the heat exchange device must be made high, so that the engine cover obstructs the rear view from the cab, which causes a problem that the workability and the like are reduced.

In addition, a dustproof net is provided upstream of the radiator and the oil cooler to prevent dust from accumulating on the radiator and the oil cooler and lowering the cooling efficiency. Since other devices are adjacent to the periphery of the device, it is configured to be inserted and removed upward and downward to be attached and detached.

However, since there is an air pipe above the dust-proof net, when the dust-proof net is attached and detached to clean the dust-proof net, the air pipe must be removed, which requires a lot of work. There is a problem that it is necessary.

[0012] The present invention has been made in view of the above-mentioned problems of the prior art, and an object of the present invention is to improve the rear view by removing piping from above the first heat exchanger.
An object of the present invention is to provide a construction machine capable of improving workability.

[0013]

A construction machine according to the present invention comprises a frame provided with a working device on the front side, left and right side covers and a top cover defining a machine room on the frame. A building cover having an engine cover provided on the top cover, an engine mounted in the building cover in a horizontal state extending leftward and rightward at the rear side of the frame, and a balance between the working device and the engine; And a counter weight attached to the rear end of the frame to allow the frame to be rotated.

Then, in order to solve the above-mentioned problem,
The first aspect of the present invention is characterized in that the first heat exchanger is provided on one of the left and right sides of the engine, the upper part of which protrudes from the top cover of the building cover and is housed in the engine cover. A second heat exchanger which is located on the opposite side of the engine with the first heat exchanger interposed therebetween and which is provided in the thickness direction of the first heat exchanger and which is overlapped with the upper cover of the building cover. A first fluid pipe connected to the second heat exchanger at a high position through a widthwise front side of the first heat exchanger and a first fluid exchanger at a position higher than an upper surface of the counterweight; A second heat exchanger connected to the second heat exchanger through the rear side in the width direction;
Fluid piping.

[0015] With this configuration, the distance between the first heat exchanger and the building cover and the distance between the first heat exchanger and the counterweight can be increased without increasing the distance between the first heat exchanger and the counterweight. Because each fluid piping can be eliminated from
The height dimension of the engine cover can be kept low, and the rear view can be improved.

Further, as in the second aspect of the present invention, the first heat exchanger is a radiator for cooling cooling water from the engine or an oil cooler for cooling hydraulic oil, and the second heat exchanger is connected to the engine. An intercooler for cooling the compressed air from the provided supercharger may be used.

According to a third aspect of the present invention, a dustproof net is provided so as to be able to be inserted and removed in an upward and downward direction so as to overlap the first heat exchanger.
The fluid pipe and the second fluid pipe are disposed before and after the dustproof net.

[0018] With this configuration, dust in the cooling air can be caught by the dust-proof net and dust can be prevented from accumulating on the first heat exchanger. When cleaning the dustproof net, since there is no fluid pipe above the first heat exchanger, the dustproof net can be easily removed by pulling the dustproof net upward.

According to a fourth aspect of the present invention, the second heat exchanger is provided such that an upper portion thereof protrudes from the upper cover of the building cover and is housed in the engine cover, and the first fluid pipe is connected to the first fluid pipe. The port is disposed at a position higher than the top cover of the building cover and in the widthwise front side of the first heat exchanger, and the pipe connection port to which the second fluid pipe is connected is the first port at a position higher than the upper surface of the counterweight. Is arranged on the rear side in the width direction of the heat exchanger.

[0020] With this configuration, the first fluid pipe and the second fluid pipe can be linearly connected to the respective pipe connection ports, and the first fluid pipe and the second fluid pipe can be connected. Since the length dimension can be shortened, the loss when the fluid flows can be reduced. Also, the connection work of each fluid pipe can be facilitated.

According to a fifth aspect of the present invention, the second heat exchanger is a first heat exchanger.
A connection pipe, which is disposed at an intermediate position in the height direction of the heat exchanger and is connected to the first fluid pipe, includes a vertical pipe section extending upward from the second heat exchanger, and an upper end of the vertical pipe section. And a horizontal pipe portion which is bent and extends in the horizontal direction so as to pass through the front side in the width direction of the first heat exchanger at a position higher than the upper surface cover of the building cover from the portion, and the second fluid pipe is connected. The connecting pipe has a vertical pipe section extending upward from the second heat exchanger, and a rear side in the width direction of the first heat exchanger at a position higher than the upper surface of the counterweight from an upper end of the vertical pipe section. And a horizontal pipe portion which is bent in the horizontal direction so as to pass therethrough.

With this configuration, each vertical pipe can be extended to a position higher than the upper surface of the building cover and the upper surface of the counterweight, and each horizontal pipe can be extended in the width direction of the first heat exchanger. The front and rear sides can pass through.
Thus, the second heat exchanger can be arranged at an intermediate position in the height direction of the first heat exchanger, and the cooling air can be efficiently applied to the second heat exchanger.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A construction machine according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings, taking a hydraulic shovel as an example.

First, FIGS. 1 to 5 show a first embodiment of the present invention. 1 is a lower traveling body, 2 is an upper revolving body mounted on the lower traveling body 1 so as to be capable of turning. The upper swing body 2 is generally constituted by a swing frame 3 described later, a building cover 11, an engine 15, a counterweight 19, a radiator 20, an oil cooler 21, an intercooler 24, an inflow pipe 28, and an outflow pipe 29.

Reference numeral 3 denotes a revolving frame which forms a structure serving as a base of the upper revolving unit. The revolving frame 3 comprises, as shown in FIG. , And a plurality of overhanging beams 6, 7 connecting the center frames 4 and the side frames 5, provided on the left and right sides of the left and right sides.
The lower side of the turning frame 3 is covered with an under cover 8.

A working device 9 for excavating earth and sand is provided on the front side of the revolving frame 3 so as to be able to move up and down. A cab 10 is provided on the left side of the working device 9. Further, a working device 9 is provided at the rear end of the turning frame 3.
A counterweight 19 is mounted to balance the weight.

Reference numeral 11 denotes a building cover that defines a machine room on the revolving frame 3. The building cover 11 extends in the front-rear direction along the side frames 5 and 5, as shown in FIGS. Left and right side covers 12, 1 standing upright
2 and an upper surface cover 13 extending in the horizontal direction over each side cover 12 and having an opening 13A formed in the center, and each side cover 12 has an air flow opening 12A comprising a plurality of slits. Are provided respectively.

Reference numeral 14 denotes an engine cover rotatably mounted on the upper cover 13 of the building cover 11. The engine cover 14 is provided with an opening 13 of the upper cover 13.
A opens and closes.

Reference numeral 15 denotes an engine provided inside the building cover 11 and mounted on the rear side of each center frame 4 so as to extend horizontally to the left and right. A cooling fan 16 is mounted on the left side of the engine 15. On the right side, a hydraulic pump 17 that is driven by the engine 15 and supplies hydraulic oil (pressure oil) to actuators (both not shown) provided on the lower traveling body 1, the working device 9, and the like is attached. I have.

Here, the cooling fan 16 is driven by the engine 15 to rotate, so that the side cover 1 is rotated.
The outside air is sucked into the building cover 11 from the air circulation port 12A of the second cooler 2, and the outside air is used as cooling air to cool the
4. The oil cooler 21 and the radiator 20 are sequentially supplied.

Reference numeral 18 denotes a turbocharger provided in the engine 15. The turbocharger 18 has a drive-side turbine chamber connected to an exhaust manifold and a muffler, and a driven-side turbine chamber connected to an inflow pipe 28 described later. And an intake hose from the air cleaner (both not shown).
The turbocharger 18 uses the exhaust gas of the engine 15 to rotate the turbine, compresses the air taken from the air cleaner, and supplies the compressed air to the intake manifold of the engine 15 via the intercooler 24 and the like.

A counterweight 19 is attached to the rear end of each center frame 4 of the revolving frame 3 and balances with the working device 9.
As shown in FIG. 5, a substantially flat front surface 19A is formed.
A peripheral surface 19B formed in an arc shape from both left and right side surfaces to a rear surface; an upper surface 19C substantially flush with the upper surface cover 13 of the building cover 11; And a lower surface 19D that forms the same plane.

Reference numeral 20 denotes a first cover provided in the building cover 11.
A radiator that forms a heat exchanger of the radiator 20,
At a position adjacent to the left side of the cooling fan 16, it is bolted on the overhanging beams 6, 6 of the revolving frame 3.
The radiator 20 is configured such that the upper tank 20A and the lower tank 20B are connected to a water jacket (not shown) of the engine 15 via a pipe, thereby radiating heat of engine cooling water circulating with the engine 15. The heat is exchanged in the section 20C and released into the cooling air to cool the engine cooling water.

An oil cooler 21 is a first heat exchanger mounted on the left side of the radiator 20 so as to form a first heat exchanger.
The lower tank 21B is connected to a hydraulic oil tank (neither is shown) via a pipe, which is connected to a return pipe from each actuator such as the working device 9 or the like. This allows
The oil cooler 21 releases the heat of the hydraulic oil at the heat radiating portion 21C, and cools the hydraulic oil.

Here, the radiator 20 and the oil cooler 2
Reference numeral 1 denotes a large-sized one for improving cooling efficiency of engine cooling water and hydraulic oil. Further, the upper swing body 2 (the building cover 11) is miniaturized in order to improve the work performance. As a result, the radiator 20 and the oil cooler 21 have their upper tanks 20A and 21A sides (upper portions) protruding from an opening 13A formed in the upper cover 13 of the building cover 11, and are housed in the engine cover 14.

Reference numeral 22 denotes a dust-proof net provided on the left side of the oil cooler 21. In the dust-proof net 22, relatively large dust is deposited on the heat radiating portion 21C of the oil cooler 21 and the heat radiating portion 20C of the radiator 20. The guide members 23 have a substantially L-shaped cross section and extend upward and downward at both ends in the width direction of the oil cooler 21.
Held in between. The dustproof net 22 is pulled up and down along each guide member 23, and is pulled out upward when removing the captured dust.

24 is an oil cooler 21, a radiator 20
The intercooler 24 is located on the opposite side of the engine 15 with respect to the engine 15 and overlapped in the thickness direction of the oil cooler 21 as a second heat exchanger. An inflow-side tank 25 located on the counterweight 19 side), and an outflow-side tank 26 located on the widthwise front side (the cab 10 side) of the oil cooler 21.
It is provided between the tanks 25 and 26, and is generally constituted by a plurality of thin tubes and a radiating portion 27 composed of radiating fins.

On the upper side of the inflow-side tank 25, an arc-shaped convex portion 25A is provided so as to protrude toward the rear side (counter weight 19 side). The arc-shaped convex portion 25A extends toward the engine 15 side. A connection pipe 25B as a pipe connection port that forms a part of the inflow pipe 28 is integrally provided. on the other hand,
An arc-shaped convex portion 26A is provided on the upper side of the outflow-side tank 26 so as to project toward the front side (toward the cab 10).
A is integrally provided with a connection pipe 26B extending toward the engine 15 and serving as a pipe connection port that forms a part of the outflow pipe 29.

Here, connection pipe 25 of inflow side tank 25
B and the connection pipe 26B of the outflow-side tank 26 are arranged with a clearance larger than the width of the radiator 20 and the oil cooler 21, so that when the intercooler 24 is attached to the oil cooler 21, the connection pipe Reference numeral 25B is disposed on the rear side in the width direction of the radiator 20 and the oil cooler 21, and the connection pipe 26B is disposed on the front side in the width direction of the radiator 20 and the oil cooler 21.

The intercooler 24 constructed as described above
Is bolted to the upper side of the oil cooler 21, and the arc-shaped convex portion 25 A of the inflow-side tank 25 is located at a position higher than the upper surface 19 C of the counterweight 19.
And the arc-shaped convex portion 2 of the outflow-side tank 26
6A is disposed at a position higher than the top cover 13 of the building cover 11 and close to the top cover 13.

The intercooler 24 is connected to the engine 1
The air compressed by the turbocharger 18 of FIG. 5 flows into the inflow-side tank 25 through an inflow pipe 28 to be described later, and is circulated by the radiator 27, thereby cooling the compressed air. The gas is supplied to the intake manifold of the engine 15 through the outflow pipe 29.

Reference numeral 28 denotes an inflow pipe which forms a second fluid pipe connecting the turbocharger 18 of the engine 15 and the intercooler 24. The inflow pipe 28 has a rubber hose 28 at one end.
A is connected to the turbine chamber on the driven side of the turbocharger 18 via A, and the other end is connected to a connection pipe 25B of the inflow-side tank 25 via a rubber hose 28A. The inflow pipe 28 is routed so as to pass behind the radiator 20 and the oil cooler 21 in the width direction at a position higher than the upper surface 19 </ b> C of the counterweight 19.

An outlet pipe 29 is a first fluid pipe connecting the intercooler 24 and the engine 15. The outlet pipe 29 has one end connected to a connection pipe 26B of the outlet tank 26 via a rubber hose 29A. The other end is connected to an intake manifold of the engine 15. The outflow pipe 29 is located on the opposite side of the inflow pipe 28 and is routed so as to pass through the front of the radiator 20 and the oil cooler 21 in the width direction at a position higher than the upper surface cover 13 of the building cover 11.

The hydraulic shovel according to the present embodiment has the above-described configuration. When the hydraulic pump 17 is driven by the engine 15, the hydraulic pump 17 applies pressure to each actuator of the lower traveling body 1 and the working device 9. Oil is supplied, and the lower traveling body 1 is caused to travel, and the work device 9 is raised and lowered to perform excavation work on earth and sand.

On the other hand, when the engine 15 is operating, the cooling fan 16 is driven to rotate by the engine 15, and the outside air is sucked into the building cover 11 as cooling air, and the cooling air is intercooled 24, the oil cooler 21, and the radiator 20. To cool the intake air, hydraulic oil and engine cooling water.

Although a lot of dust is mixed in the cooling air, the dust can be caught by the dust-proof net 22 and the cooling efficiency of the oil cooler 21 and the radiator 20 decreases due to the accumulation of the dust. Can be prevented. Moreover, when removing the dust trapped on the dust-proof net 22, the dust-removal work can be easily performed by pulling the dust-proof net 22 upward.

As described above, according to the present embodiment, the inflow pipe 28 connecting the engine 15 and the intercooler 24 is located at a position higher than the upper surface 19C of the counterweight 19 and passes through the rear side in the width direction of the radiator 20 and the oil cooler 21. The radiator 20 and the oil cooler 2 at a position higher than the top cover 13 of the building cover 11.
1 through the front side in the width direction.

Accordingly, the inflow pipe 28 and the outflow pipe 29 can be routed without increasing the distance between the radiator 20, the oil cooler 21 and the building cover 11, and the distance between the radiator 20, the oil cooler 21 and the counterweight 19. Therefore, the front and rear dimensions of the upper swing body 2 can be reduced, and the turning radius of the upper swing body 2 can be reduced to improve the work performance.

Moreover, the radiator 20 and the oil cooler 2
By eliminating the inflow pipe 28 and the outflow pipe 29 from the upper side of 1, the height of the engine cover 14 can be reduced, so that the rear view from the cab 10 can be improved, and workability and safety can be improved. Can be increased.

The inflow pipe 28 is connected to the counterweight 1
9 and the outflow pipe 29 is arranged at a position higher than the building cover 11, so that the width of the intercooler 24 can be made as large as the width of the radiator 20 and the oil cooler 21. it can. Thereby, the cooling efficiency of the intercooler 24 can be improved, and the performance of the engine 15 can be improved.

Further, since the intercooler 24 is disposed above the oil cooler 21, an inflow path composed of the connection pipe 25B of the inflow-side tank 25 and the inflow pipe 28, and a connection pipe 26B of the outflow-side tank 26 and the outflow. The outflow path formed by the pipe 29 can be shortened. Thus, the performance of the engine 15 can be improved by reducing the air flow resistance, and the cost can be reduced, the workability at the time of maintenance can be improved, and the like.

On the other hand, when cleaning the dust-proof net 22, since there is no obstructive piping above the dust-proof net 22,
The dustproof net 22 can be easily pulled out, and the work of cleaning the dustproof net 22 can be facilitated, and the workability can be improved.

Next, FIGS. 6 and 7 show a second embodiment of the present invention. The feature of this embodiment is that the second heat exchanger is arranged in the height direction of the first heat exchanger. Placed in the middle of
The second heat exchanger is connected to the first and second fluid pipes via connection pipes. In the present embodiment, the same components as those in the above-described first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

Reference numeral 31 denotes an intercooler according to the present embodiment which is used in place of the intercooler 24 according to the first embodiment. The intercooler 31 is provided on the rear side in substantially the same manner as the intercooler 24 according to the first embodiment. An inflow-side tank 32 positioned therein, and an outflow-side tank 33 positioned on the front side,
It is provided between each of the tanks 32 and 33, and is generally constituted by a plurality of thin tubes and a heat radiating portion 34 composed of heat radiating fins.

However, the intercooler 31 according to the present embodiment is arranged at an intermediate position in the height direction of the oil cooler 21, and the connection pipe 35 of the inflow-side tank 32 is correspondingly arranged.
The point that the connection pipe 36 of the outflow side tank 33 and the outflow side tank 33 are formed to be long is that the intercooler 24 according to the first embodiment.
Is different.

Reference numeral 35 denotes an inflow-side connection pipe integrally provided at an upper end portion of the inflow-side tank 32.
As shown in FIG. 7, a vertical pipe portion 35A extending upward from the upper end surface of the inflow-side tank 32, and a horizontal pipe portion bent to the engine 15 side after being bent rearward from the upper end portion of the vertical pipe portion 35A. And a unit 35B. The top side of the counterweight 19 is located on the tip side of the horizontal piping portion 35B.
Oil cooler 21 and radiator 20 at a position higher than C
The inflow pipe 28 is connected to the end of the horizontal pipe 35B via a rubber hose 28A.

Reference numeral 36 denotes an outflow-side connection pipe integrally provided at an upper end portion of the outflow-side tank 33.
The vertical piping section 3 extending upward from the upper end surface of the outflow side tank 33
6A, and a horizontal pipe portion 36B which is bent forward from the upper end of the vertical pipe portion 36A and then bent toward the engine 15 side. The distal end of the horizontal piping portion 36B is disposed at a position higher than the upper surface cover 12 of the building cover 11 in front of the oil cooler 21 and the radiator 20 in the width direction, and a rubber hose 29 is provided at the distal end side of the horizontal piping portion 36B.
Outlet pipe 29 is connected via A.

Thus, in the present embodiment configured as described above, substantially the same operation and effect as those in the first embodiment can be obtained. In particular, in the present embodiment, the intercooler 31 is Since the oil cooler 21 can be disposed at an intermediate position in the height direction, the cooling air can be efficiently applied to the intercooler 31 to cool the air, and the performance of the engine 15 can be further improved.

In each of the embodiments, the intercoolers 24 and 31 have been described as examples of the second heat exchanger. However, the present invention is not limited to this. For example, the air conditioner may be used as the second heat exchanger. May be applied.

In each embodiment, the turbocharger 1
8 is disposed on the rear side of the engine 15 so that the outflow pipe 29 is disposed on the front side (the cab 10 side) as a first fluid pipe, and the inflow pipe 28 is disposed on the rear side (the counterweight 19 side) as a second fluid pipe. ) Has been described as an example. However, the present invention is not limited to such an arrangement. When the arrangement of the engine 15 is switched between left and right, that is, when the turbocharger 18 is disposed on the front side, the first fluid pipe The inflow pipe 28 serving as the second fluid pipe may be provided on the front side, and the outflow pipe 29 serving as the second fluid pipe may be provided on the rear side.

Further, in the embodiments, the description has been given by taking the hydraulic excavator as an example of the construction machine. However, the present invention is not limited to this, and is applicable to other construction machines such as a wheel loader, a hydraulic crane, and a bulldozer. May be.

[0062]

As described above in detail, according to the first aspect of the present invention, the engine is provided on one side in the left and right directions, and the upper portion protrudes from the upper surface cover of the building cover and is housed in the engine cover. A first heat exchanger such as a radiator, an oil cooler, etc., and an intercooler provided on the opposite side to the engine with the first heat exchanger interposed therebetween and superposed in the thickness direction of the first heat exchanger. And a first fluid pipe connected to the second heat exchanger through a widthwise front side of the first heat exchanger at a position higher than the upper surface cover of the building cover. And passing through the widthwise rear side of the first heat exchanger at a position higher than the upper surface of the
And a second fluid pipe connected to the heat exchanger. Accordingly, each fluid pipe can be eliminated from the upper side of the first heat exchanger without increasing the distance between the first heat exchanger and the building cover and the distance between the first heat exchanger and the counterweight. As a result, the height of the engine cover can be kept low, the rear visibility can be improved, and the workability and safety can be improved.

According to the third aspect of the invention, dust in the cooling air can be caught by the dust-proof net, so that dust can be prevented from being deposited on the first heat exchanger. Cooling efficiency can be increased. In addition, when cleaning dust caught by the dust-proof net, since there is no fluid pipe above the first heat exchanger, the dust-proof net can be easily removed by pulling the dust-proof net upward. Performance can be improved.

According to the fourth aspect of the present invention, the second heat exchanger is provided in a state where the upper part thereof protrudes from the building cover and is housed in the engine cover, and the pipe connection port to which the first fluid pipe is connected. Is disposed at a position higher than the upper surface cover of the building cover and in the widthwise front side of the first heat exchanger, and a pipe connection port to which the second fluid pipe is connected is provided at a position higher than the upper surface of the counterweight. Since it is configured to be disposed on the rear side in the width direction of the heat exchanger, the first fluid pipe and the second fluid pipe can be linearly connected to the respective pipe connection ports,
By shortening the length of the first fluid pipe and the second fluid pipe, the loss when the fluid flows can be reduced and the cooling efficiency can be improved. Also, the connection work of each fluid pipe can be facilitated, and the assembling workability can be improved and the cost can be reduced.

According to the fifth aspect of the present invention, the second heat exchanger is arranged at an intermediate position in the height direction of the first heat exchanger,
The connection pipe to which the fluid pipe is connected and the connection pipe to which the second fluid pipe is connected are a vertical pipe section extending upward from the second heat exchanger, and a building cover from the upper end of the vertical pipe section. The top cover and the counterweight are also located at a higher position near the top.
The second heat exchanger is constituted by a horizontal pipe portion which is bent in the lateral direction so as to pass through the front side and the rear side in the width direction of the first heat exchanger. In the middle position in the direction, efficiently apply cooling air to the second heat exchanger,
The cooling performance of the second heat exchanger can be improved.

[Brief description of the drawings]

FIG. 1 is a front view showing a hydraulic excavator applied to a first embodiment of the present invention.

FIG. 2 shows an engine, a heat exchange device, etc. as shown by arrows II-II in FIG.
It is sectional drawing expanded and shown from a direction.

FIG. 3 is a plan view of a main part showing a main part in a building cover in a state where an engine cover is omitted from a rear side of the upper revolving structure.

FIG. 4 is an external perspective view showing the arrangement of an inflow pipe and an outflow pipe together with an engine, an intercooler, a counterweight, and the like.

FIG. 5: Building cover, counterweight, radiator,
FIG. 5 is a cross-sectional view of an oil cooler, an intercooler, and the like, as viewed from a direction indicated by arrows VV in FIG. 2.

FIG. 6 is a sectional view showing an intercooler according to a second embodiment of the present invention together with a building cover, a counterweight, an oil cooler, and the like.

7 is an external perspective view showing the intercooler in FIG. 6 in an enlarged manner from the engine side.

[Explanation of symbols]

 Reference Signs List 3 Revolving frame 9 Working device 11 Building cover 12 Side cover 13 Top cover 14 Engine cover 15 Engine 18 Turbocharger 19 Counterweight 19A Front 19B Peripheral surface 19C Upper surface 19D Lower surface 20 Radiator (first heat exchanger) 21 Oil cooler (First heat exchanger) 22 Dust-proof net 24, 31 Intercooler (second heat exchanger) 25, 32 Inlet-side tank 25B, 26B Connection pipe (piping connection port) 26, 33 Outflow-side tank 28 Inflow pipe (No. 2 fluid piping) 29 Outflow piping (first fluid piping) 35, 36 Connection piping 35A, 36A Vertical piping (vertical piping) 35B, 36B Horizontal piping (horizontal piping)

 ──────────────────────────────────────────────────の Continued on the front page (72) Koji Tahara, Inventor Kojimachi, Tsuchiura-city, Ibaraki Pref.Hitachi Construction Machinery Co., Ltd. Tsuchiura Plant (72) Koji Kawasaki, 650-Kamidate-cho, Tsuchiura-City, Ibaraki Hitachi 3D038 AA04 AA05 AA10 AB09 AC02 AC25

Claims (5)

[Claims] 1. A frame having a working device provided on a front side thereof, left and right side covers and a top cover defining a machine room on the frame, and an engine cover is provided on the top cover. A building cover, an engine mounted inside the building cover, and mounted in a horizontal state extending leftward and rightward on the rear side of the frame, and attached to a rear end of the frame to balance with the working device. A first heat exchanger provided on one side in the left and right directions of the engine, and having an upper part protruding from an upper surface cover of the building cover and housed in the engine cover. A second heat exchanger located on the opposite side of the engine with the first heat exchanger interposed therebetween and provided in a thickness direction of the first heat exchanger, and an upper surface of the building cover; cover A first fluid pipe connected to the second heat exchanger through a widthwise front side of the first heat exchanger at a position higher than the first heat exchanger; and a first fluid pipe at a position higher than an upper surface of the counterweight. And a second fluid pipe connected to the second heat exchanger through a widthwise rear side of the heat exchanger. 2. The first heat exchanger is a radiator that cools cooling water from the engine or an oil cooler that cools hydraulic oil, and the second heat exchanger is a supercharger provided in the engine. The construction machine according to claim 1, wherein the construction machine is an intercooler for cooling compressed air from the air conditioner. 3. A dustproof net is provided on the first heat exchanger so as to be able to be inserted and removed in an upward and downward direction, and the first fluid pipe and the second fluid pipe are provided with the dustproof net sandwiched therebetween. ,
The construction machine according to claim 1 or 2, which is arranged later. 4. The second heat exchanger is provided with its upper part protruding from an upper surface cover of the building cover and housed in an engine cover, and a pipe connection port to which the first fluid pipe is connected is provided. It is arranged at a position higher than the upper surface cover of the building cover on the widthwise front side of the first heat exchanger, and a pipe connection port to which the second fluid pipe is connected is at a position higher than the upper surface of the counterweight. 4. The construction machine according to claim 1, wherein the construction is arranged on a rear side in the width direction of the first heat exchanger. 5. 5. The second heat exchanger is disposed at an intermediate position in the height direction of the first heat exchanger, and the connection pipe to which the first fluid pipe is connected is a second heat exchanger. A vertical pipe portion extending upward from the upper portion of the vertical pipe portion, and bent laterally so as to pass through the widthwise front side of the first heat exchanger at a position higher than the upper surface cover of the building cover. A connection pipe connected to the second fluid pipe, the connection pipe being configured by an extended horizontal pipe section, and a vertical pipe section extending upward from the second heat exchanger;
A horizontal pipe extending from the upper end of the vertical pipe at a position higher than the upper surface of the counter weight so as to bend in the horizontal direction so as to pass through the widthwise rear side of the first heat exchanger. The construction machine according to claim 1, 2 or 3.