JP2014148858A - Construction machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a construction machine capable of ensuring a flow of cooling air even though an exhaust gas treatment device is provided in a house frame.SOLUTION: A construction machine includes an engine 20 generating cooling air 39 by driving a cooling fan 23, an exhaust gas treatment device 30 treating exhaust gas exhausted from the engine 20, and a house frame 35 placed downstream of the engine 20 in a flow of the cooling air 39. The exhaust gas treatment device 30 is arranged in the house frame 35, and an air guide passage 38 through which the cooling air 39 flows is formed in the house frame 35.

Description

  The present invention relates to a construction machine having an exhaust gas processing device for processing exhaust gas discharged from an engine.

  Conventionally, in a construction machine such as a hydraulic excavator equipped with a diesel engine (hereinafter simply referred to as an engine), an exhaust gas treatment device is installed in an exhaust system of the engine. The exhaust gas from the engine is released into the atmosphere after the suspended particulate matter (PM) and nitrogen oxides (NOx) are removed by the exhaust gas treatment device provided downstream of the exhaust pipe. Yes.

  Conventionally, this exhaust gas treatment device has been configured to be integrally attached to the engine in the engine compartment. Further, as shown in FIGS. 5 and 6 of Patent Document 1, the diesel particulate filter (DPF) and the selective reduction catalyst (SCR) constituting the exhaust gas treatment device are separated and each is attached to the engine in parallel. Things were also done.

JP 2009-184558 A

  However, in recent years, higher-order exhaust gas regulations have been demanded, and exhaust gas treatment apparatuses (DPF, SCR, etc.) tend to be larger and heavier in order to comply with these higher-order exhaust gas regulations. When the exhaust gas processing device becomes larger and heavier, it is difficult to support it in the engine. For this reason, the structure which supports an exhaust-gas processing apparatus in the house frame provided in the turning body is proposed.

  Incidentally, the engine is provided with a cooling fan, and the cooling fan is rotated to generate cooling air. The cooling air cools the cooling water for the engine, the hydraulic oil for the hydraulic equipment, and the like in the heat exchange device. In addition, the cooling air that has passed through the heat exchange device passes through the engine side and is discharged to the outside of the engine compartment.

  However, the exhaust gas treatment device is disposed on the opposite side via the engine with respect to the position where the heat exchange device is disposed. That is, the exhaust gas treatment device is configured to be disposed on the downstream side of the engine with respect to the flow direction of the cooling air.

  Thus, when the exhaust gas processing apparatus enlarged in size is provided on the downstream side of the engine, the flow path of the cooling air is obstructed by the exhaust gas processing apparatus and is not discharged well from the engine chamber. Therefore, the heat exchange efficiency in the heat exchange device may be reduced, and the heat balance may be deteriorated.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a construction machine that can ensure the flow of cooling air even if an exhaust gas treatment device is provided in a house frame.

From the first point of view, the above problem is
An engine that generates cooling air by driving a cooling fan;
An exhaust gas processing device for processing exhaust gas discharged from the engine;
A construction machine having a house frame disposed on the downstream side of the engine with respect to the flow of the cooling air,
The exhaust gas treatment device is disposed in the house frame,
And it can solve with the construction machine characterized by having formed the wind guide path through which the said cooling wind flows in the said house frame.

  According to the disclosed invention, by forming the air guide path through which the cooling air flows in the house frame, it is possible to secure a flow path of the cooling air and prevent a decrease in heat balance.

FIG. 1 is a side view of a construction machine according to an embodiment of the present invention. FIG. 2 is a cross-sectional view showing a schematic configuration of an engine room of a construction machine according to an embodiment of the present invention. FIG. 3 is a partially enlarged perspective view of the engine room of the construction machine according to the embodiment of the present invention. FIG. 4 is a perspective view showing a house frame disposed on a construction machine according to an embodiment of the present invention. FIG. 5 is a side view showing a house frame disposed on a construction machine according to an embodiment of the present invention. FIG. 6 is a front view showing a house frame disposed in a construction machine according to an embodiment of the present invention.

  Next, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows a construction machine according to an embodiment of the present invention. In the present embodiment, a hydraulic excavator 1 will be described as an example of a construction machine.

  The hydraulic excavator 1 is roughly constituted by a crawler-type lower traveling body 2 that can be self-propelled and an upper revolving body 3 that is rotatably mounted on the lower traveling body 2. A work attachment 4 is provided on the front side of the upper swing body 3.

  The work attachment 4 includes a boom 6, an arm 9, a bucket 10, and the like. The boom 6 is attached to a turning frame 5 described later so as to be able to move up and down. The arm 9 is rotatably attached to the tip end side of the boom 6. Moreover, the bucket 10 is attached to the front end side of the arm 9 so that rotation is possible.

  The boom cylinder 12 is disposed between the turning frame 5 and the boom 6. The boom 6 moves up and down with respect to the revolving frame 5 by the boom cylinder 12. The arm cylinder 13 is disposed between the boom 6 and the arm 9. The arm 9 rotates with respect to the boom 6 by the arm cylinder 13. Further, the bucket cylinder 14 is disposed between the bucket 10 and the arm 9. The bucket 10 is rotated with respect to the arm 9 by the bucket cylinder 14.

  The upper revolving unit 3 is installed on the lower traveling unit 2 through a revolving mechanism 16 so as to be able to revolve. As shown in FIG. 2 in addition to FIG. 1, the upper swing body 3 includes a swing frame 5, a cab 8, a counterweight 15, an exterior cover (exterior body) 18, an engine hood 17 a, an engine 20, a heat exchange device 24, An exhaust gas treatment device 30, a house frame 35, connection devices 50A and 50B, and the like are disposed.

  The cab 8 is provided on the revolving frame 5, and a driver's seat (not shown) is provided therein. The operator sits on the driver's seat in the cab 8 and operates the hydraulic excavator 1.

  The counterweight 15 has a function of balancing the weight with the work attachment 4. The exterior cover 18 and the engine hood 17a cover the engine 20, the heat exchange device 24, the exhaust gas processing device 30 and the like disposed in the engine chamber 17.

  Next, the configuration inside the engine chamber 17 will be described.

  FIG. 2 is a schematic configuration diagram showing the internal configuration of the engine chamber 17, and FIG. 3 is an enlarged perspective view showing the vicinity of the engine 20 in the engine chamber 17.

  In the engine chamber 17, an engine 20, a heat exchange device 24, an exhaust gas processing device 30, a house frame 35, and the like are disposed.

  The engine 20 is supported on an upper part of an engine mounting seat 21 disposed on the revolving frame 5 via a mount 22. The mount 22 is an anti-vibration mount and prevents vibration generated by the engine 20 from being transmitted to the turning frame 5.

  A cooling fan 23 is disposed on the X1 direction side (left side in the figure) of the engine 20. A heat exchange device 24 is disposed on the X1 direction side of the cooling fan 23.

  The cooling fan 23 is rotationally driven by the engine 20. As the cooling fan 23 is driven to rotate, outside air is taken into the engine compartment 17 as cooling air 39. The heat exchange device 24 performs heat exchange processing with the cooling air 39 taken into the engine chamber 17.

  The cooling air 39 flows in the right direction in the figure as indicated by an arrow in FIG. Therefore, the arrow X1 direction side in the figure is the cooling air upstream side, and the arrow X2 direction in the figure is the cooling air downstream side.

  The heat exchanging device 24 is supplied to an oil cooler and an engine for dissipating hydraulic fluid from hydraulic equipment such as a radiator that cools cooling water flowing in the engine 20, a boom cylinder 12, an arm cylinder 13, and a bucket cylinder 14. A radiator unit 24A provided with an intercooler for cooling the supercharged air, a fuel cooler 24B for cooling excess fuel returning to a fuel tank (not shown), and a condenser 24C for an air conditioner are provided. .

  The cooling water, hydraulic oil, supercharged air, surplus fuel, and the like are cooled by the cooling air 39. Therefore, the temperature of the cooling air 39 rises as it passes through the heat exchange device 24.

  A hydraulic pump 27 is integrally attached to the X2 direction side of the engine 20. The hydraulic pump 27 is a hydraulic source such as the boom cylinder 12, the arm cylinder 13, and the bucket cylinder 14 that drive the work attachment 4. This hydraulic pump 27 is also driven by the engine 20.

  Exhaust gas discharged from the engine 20 is purified by the exhaust gas processing device 30. The exhaust gas discharged from the engine 20 may contain harmful substances such as nitrogen oxides (NOx), and an exhaust gas processing device 30 is connected to the engine 20 to purify them.

  The exhaust gas processing device 30 corresponds to a diesel particulate filter 31 (a first exhaust gas processing unit described in claims) that collects particulate matter (PM) contained in exhaust gas. ) And a selective reduction catalyst 32 for reducing and removing nitrogen oxide (NOx) using a selective reducing agent (for example, urea or the like). (Hereinafter referred to as SCR) and the like. Further, the DPF 31 includes a front-stage oxidation catalyst on the upstream side, and the SCR 32 includes a rear-stage oxidation catalyst on the downstream side. The DPF 31 may be an oxidation catalyst-carrying filter (CSF).

  The exhaust gas treatment device 30 and the house frame 35 that supports the exhaust gas treatment device 30 are shown in FIGS. 4 to 6 in addition to FIG.

  Since the exhaust gas treatment device 30 purifies the exhaust gas exhausted from the engine 20 as described above, the exhaust gas treatment device 30 is disposed in the vicinity of the engine 20. Further, since the heat exchanging device 24 is disposed on the upstream side of the engine 20 with respect to the flow direction of the cooling air 39, the exhaust gas processing device 30 is disposed downstream of the engine 20 with respect to the flow direction of the cooling air 39 (X2 (Direction side).

  In addition, as described above, in recent years, higher-order exhaust gas regulations have been demanded, and the DPF 31 and the SCR 32 constituting the exhaust gas treatment device 30 have become larger and heavier in order to comply with these higher-order exhaust gas regulations. For this reason, it is difficult to attach the exhaust gas treatment device 30 to the engine 20 as in the prior art. Therefore, in this embodiment, the exhaust gas treatment device 30 is attached to the house frame 35 and supported by the house frame 35.

  Further, when the DPF 31 and the SCR 32 constituting the exhaust gas processing device 30 are arranged in a line, the length becomes longer than the engine width, and the engine chamber 17 cannot be made compact. For this reason, in this embodiment, the DPF 31 and the SCR 32 are separated, and the DPF 31 and the SCR 32 are arranged side by side so as to be substantially parallel.

  The exhaust gas discharged from the engine 20 is introduced into the DPF 31 via the exhaust gas pipe 29 and subjected to the first stage purification process, and then sent to the SCR 32 via a pipe (not shown) to perform the second stage purification process. And then discharged to the outside of the aircraft through the exhaust pipe 41 and the tail pipe 25. An engine hood 17 a is provided on the upper part of the engine 20 and the exhaust gas treatment device 30.

  The house frame 35 has a function of supporting the exhaust gas processing device 30 as described above. The house frame 35 is provided on the revolving frame 5. Further, the position of the house frame 35 is set on the downstream side (X2 direction side) of the engine 20 with respect to the flow direction of the cooling air 39.

  The house frame 35 includes a frame main body 36 and a support body 37. The lower part of the frame body 36 is fixed to the revolving frame 5. In addition, hydraulic parts connected to the hydraulic pump 27 are disposed inside the frame body 36. Therefore, the frame main body 36 is provided with a firewall 42 for shielding these hydraulic components and the engine 20.

  The support 37 is disposed on the upper portion of the frame body 36. The support 37 has a box shape as shown in FIGS. 3, 4, and 6. The DPF 31 constituting the exhaust gas processing device 30 is attached to the side portion of the support body 37. The DPF 31 is attached to the upper part of the support body 37.

  Thus, the exhaust gas processing device 30 is separated from the engine 20 by attaching the exhaust gas processing device 30 to the house frame 35. The exhaust gas treatment device 30 is configured to be mounted on the revolving frame 5 via the house frame 35.

  Here, the exhaust gas processing device 30 and the house frame 35 will be described in more detail.

  As described above, the house frame 35 is disposed on the downstream side of the engine 20 with respect to the flow direction of the cooling air 39. The house frame 35 is provided with hydraulic parts in the lower part thereof, and a fire wall 42 is provided at a position facing the engine 20, so that the cooling air 39 generated by the cooling fan 23 is generated by the house frame 35. 35 prevents the flow.

  In addition, a DPF 31 and an SCR 32 constituting the exhaust gas processing device 30 are provided on the upper portion of the house frame 35. As described above, the exhaust gas processing device 30 is increased in size, and is configured to be disposed up to the vicinity of the engine hood 17 a of the engine chamber 17. Therefore, the flow of the cooling air 39 generated by the cooling fan 23 is also hindered by the exhaust gas processing device 30.

  Therefore, in the present embodiment, as shown in FIGS. 3 to 6, the air guide path 38 through which the cooling air 39 flows (passes through) the house frame 35 is formed. In the present embodiment, the air guide path 38 is formed in the support body 37 disposed on the upper portion of the frame body 36.

  As described above, the support body 37 has a box shape, and the L-shaped partition plate 40 is disposed inside the rectangular frame body 43. Further, a space is formed between adjacent partition plates 40, and this space portion constitutes the air guide path 38.

  By providing the air guide path 38 as described above, the air guide path 38 is located above the frame main body 36 provided with the firewall 42 and the like and below the exhaust gas processing device 30. Therefore, as shown in FIG. 2, on the X2 direction side of the engine 20, the lower part (Z2 direction side) blocks the flow of the cooling air 39 by the firewall 42 and the like, and the upper part (Z1 direction side) is the exhaust gas processing device 30. Even if the flow of the cooling air 39 is obstructed by this, the cooling air 39 flows between the exhaust gas processing device 30 and the firewall 42 through the air guide path 38 and downstream (X2 direction side).

  As described above, the flow of the cooling air 39 is secured on the downstream side of the engine 20 with respect to the flow of the cooling air 39, so that the cooling air whose temperature is increased by passing through the heat exchange device 24 in the engine chamber 17. It can prevent that the flow of 39 deteriorates and a heat balance falls. Therefore, in the heat exchanging device 24, the engine cooling water or the like can be efficiently cooled by the cooling air 39.

  In the present embodiment, the DPF 31 and the SCR 32 constituting the exhaust gas processing device 30 are arranged (offset) by shifting in the flow direction of the cooling air 39 and the vertical direction of the upper swing body 3. Specifically, the DPF 31 and the SCR 32 are not arranged along the X1 and X2 directions (flow direction of the cooling air 39) or the Z1 and Z2 directions (up and down direction of the upper swing body 3), but relatively to the DPF 31. The SCR 32 is arranged so as to be shifted to the X2 direction side and the Z1 direction side.

  With this configuration, the flow passage area of the air guide passage 38 can be increased while reducing the height of the engine chamber 17.

  If the SCR 32 is left at the position shown in FIG. 2 and the DPF 31 is disposed below the SCR 32, the flow path of the air guide path 38 becomes narrow. Therefore, although improvement in heat balance is expected as compared with the configuration in which the air guide path 38 is not provided, sufficient improvement cannot be expected.

  As a means for solving this problem, it is conceivable that the exhaust gas processing device 30 is moved in the Z1 direction and fixed to the support body 37 in a state where the DPF 31 and the SCR 32 are overlapped in the Z1 and Z2 directions.

  In this configuration, since the flow path area of the air guide path 38 is secured, the heat balance is improved, but the position of the engine hood 17a in the engine chamber 17 is higher than the position shown in FIG. Since the exhaust gas processing device 30 is disposed at the rear position of the cab 8, the rear view from the cab 8 is deteriorated when the engine chamber 17 becomes taller.

  On the other hand, by disposing the DPF 31 and the SCR 32 in the X1 and X2 directions and the Z1 and Z2 directions as in the present embodiment, the flow path of the cooling air 39 (indicated by an arrow FL in the figure) below the DPF 31. Is formed. Therefore, the flow path of the air guide path 38 can be secured while reducing the height of the engine chamber 17.

  The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific embodiments described above, and various modifications are possible within the scope of the gist of the present invention described in the claims. It can be modified and changed.

  For example, if there is a region where the air guide path 38 can be formed in the frame main body 36 located under the house frame 35, the air guide path 38 can be formed in the frame main body 36.

DESCRIPTION OF SYMBOLS 1 Hydraulic excavator 2 Lower traveling body 3 Upper turning body 4 Attachment 5 Turning frame 17 Engine chamber 17a Engine hood 18 Exterior cover 19 Turning frame 20 Engine 23 Cooling fan 24 Heat exchange device 27 Hydraulic pump 29 Exhaust gas piping 30 Exhaust gas processing device 31 DPF
32 SCR
35 House frame 36 Frame body 37 Support body 38 Air guide path 39 Cooling air 40 Partition plate 42 Firewall 50A First connection device 50B Second connection device

Claims (4)

An engine that generates cooling air by driving a cooling fan;
An exhaust gas processing device for processing exhaust gas discharged from the engine;
A construction machine having a house frame disposed on the downstream side of the engine with respect to the flow of the cooling air,
The exhaust gas treatment device is disposed in the house frame,
And the construction machine characterized by forming the air guide path through which the said cooling wind flows in the said house frame.   The construction machine according to claim 1, wherein the air guide path is formed at a lower position of the house frame where the exhaust gas treatment device is disposed.   The exhaust gas processing device includes a first exhaust gas processing unit and a second exhaust gas processing unit, and the first exhaust gas processing unit and the second exhaust gas processing unit are arranged in parallel with the house frame. The construction machine according to claim 1 or 2, wherein the construction machine is provided.   The construction machine according to claim 3, wherein the first exhaust gas processing unit and the second exhaust gas processing unit are arranged to be shifted in the flow direction of the cooling air.

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