JP2022066210A - Construction machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a construction machine in which an exhaust gas post-processing device and an exhaust pipe are compactly provided.

SOLUTION: An inflow port 26A of a first exhaust gas post-processing device 25, which is connected to an exhaust gas outflow side of an exhaust pipe 35, is provided on a side opposite to an engine 9 with an axis O1-O1 of the first exhaust gas post-processing device 25 interposed therebetween. A second exhaust gas post-processing device 30 is located on an upper side with respect to the first exhaust gas post-processing device 25 so as to overlap on the first exhaust gas post-processing device 25 in a vertical direction. The exhaust pipe 35 is configured from: a horizontal pipeline 36 which extends along a lengthwise direction of the engine 9 from an exhaust port 10A of the engine 9, and traverses below a cylindrical body 26, which forms the first exhaust gas post-processing device 25, in a direction orthogonal to the axis O1-O1 of the cylindrical body 26; and a bent pipeline 37 which is bent upward from a tip side of the horizontal pipeline 36, and is connected to the inflow port 26A of the first exhaust gas post-processing device 25.

SELECTED DRAWING: Figure 4

COPYRIGHT: (C)2022,JPO&INPIT

Description

The present invention relates to, for example, a construction machine such as a hydraulic excavator equipped with an exhaust gas aftertreatment device in the exhaust pipe of an engine.

In general, a hydraulic excavator as a construction machine is provided with a self-propelled lower traveling body, an upper turning body mounted on the lower traveling body so as to be able to turn, and a depression / elevation movement on the front side of the upper turning body. It is composed of a working device. The upper swivel body has a cab, a fuel tank, a hydraulic oil tank, etc. mounted on the front side of the swivel frame, and an engine, a hydraulic pump, etc. mounted on the rear side of the swivel frame.

A diesel engine is generally used as the engine of the hydraulic excavator. This diesel engine emits harmful substances such as particulate matter (PM: Particulate Matter) and nitrogen oxides (NOx). Therefore, the hydraulic excavator is provided with an exhaust gas aftertreatment device for purifying the exhaust gas in the exhaust pipe of the engine. The exhaust gas aftertreatment device includes a PM collecting device having a DPF (Diesel Particulate Filter) that collects particulate matter contained in the exhaust gas, and NOx purification that purifies nitrogen oxides (NOx) contained in the exhaust gas. The device is known. Further, as an exhaust gas aftertreatment device, a muffling device for reducing the exhaust volume is also known (see, for example, Patent Document 1).

International Publication No. 2014/196395

By the way, in the exhaust gas aftertreatment device described in Patent Document 1 described above, the first exhaust gas aftertreatment device, the second exhaust gas aftertreatment device, and the exhaust pipe are arranged in parallel in the horizontal direction (horizontal direction). It is arranged. Further, the exhaust pipe is provided with a bellows pipe having a predetermined length dimension in order to absorb a relative displacement amount with respect to vibration between the engine and the exhaust gas aftertreatment device. Therefore, in order to dispose the exhaust gas aftertreatment device, the exhaust pipe, and the bellows pipe, a large space may be required in the front, rear, left, and right directions of the vehicle body.

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 provide a construction machine in which an exhaust gas aftertreatment device and an exhaust pipe are compactly arranged.

The construction machine according to the present invention includes a self-propelled vehicle body, an engine mounted on the vehicle body, an aftertreatment device mount provided on the vehicle body, an exhaust pipe connected to an exhaust port of the engine, and the exhaust gas. A first exhaust gas aftertreatment device composed of a cylinder provided on the exhaust gas outflow side of the pipe, a connection pipe connected to the exhaust gas outflow side of the first exhaust gas aftertreatment device, and the connection pipe. A second exhaust gas aftertreatment device composed of a cylinder provided on the exhaust gas outflow side is provided, and the first exhaust gas aftertreatment device and the second exhaust gas aftertreatment device are the posttreatment. The inflow port of the first exhaust gas aftertreatment device, which is attached to the device frame and to which the exhaust gas outflow side of the exhaust pipe is connected, is the cylinder of the cylinder forming the first exhaust gas aftertreatment device. The second exhaust gas aftertreatment device, which is provided on the opposite side of the engine with the axis line interposed therebetween, overlaps the first exhaust gas aftertreatment device in the upward and downward directions. It is located above the device.

The feature of the present invention is that the exhaust pipe has a horizontal pipe line that crosses the lower part of the cylinder forming the first exhaust gas aftertreatment device from the exhaust port of the engine, and the tip of the horizontal pipe line. It is composed of a bending pipeline that bends upward from the side and is connected to the inlet of the first exhaust gas aftertreatment device, and an intermediate portion of the bending pipeline is described from the aftertreatment device stand to the above. A bellows tube that protrudes toward the opposite side of the engine and absorbs the relative displacement between the engine and the first exhaust gas aftertreatment device is provided in the horizontal conduit, and the bellows is provided. The pipe, the first exhaust gas aftertreatment device, and the second exhaust gas aftertreatment device are, in order from the bottom in the upward and downward directions, the bellows pipe, the first exhaust gas aftertreatment device, and the second. The bellows pipes are arranged so as to be overlapped in the order of the exhaust gas aftertreatment devices of the above, and the bellows pipe is accommodated within the width formed by the first exhaust gas aftertreatment device and the second exhaust gas aftertreatment device. Have been placed.

According to the present invention, the space for arranging the exhaust gas aftertreatment device and the exhaust pipe can be reduced.

It is a front view which shows the hydraulic excavator which concerns on embodiment of this invention. It is a top view which shows the upper swing body in a state where a cab, a building cover, etc. are omitted. FIG. 3 is an enlarged plan view showing an engine, an exhaust gas aftertreatment device, and the like in FIG. 2. It is sectional drawing which looked at the engine, the post-treatment device pedestal, and the exhaust gas post-treatment device from the direction of arrow IV-IV in FIG. It is a perspective view which shows the post-treatment device pedestal mounted on the swivel frame, and the exhaust gas after-treatment device. It is a perspective view which shows the exhaust gas aftertreatment device attached to the post-treatment device pedestal. It is an exploded perspective view which shows the state which the cover member was removed from the post-processing apparatus pedestal. It is a side view which shows the exhaust gas aftertreatment device in FIG. 4 in an enlarged manner. It is a front view of the exhaust gas aftertreatment device as seen from the direction of arrow IX-IX in FIG. It is sectional drawing which shows typically the internal structure of the exhaust gas aftertreatment device.

Hereinafter, a crawler type hydraulic excavator will be taken as an example as a typical example of the construction machine according to the embodiment of the present invention, and will be described in detail according to the attached drawings.

The hydraulic excavator 1 shown in FIG. 1 includes a self-propelled crawler type lower traveling body 2, an upper turning body 3 mounted on the lower traveling body 2 so as to be able to turn, and front and rear directions of the upper turning body 3. It is composed of a work device 4 provided on the front side so as to be able to move up and down and perform excavation work of earth and sand. The lower traveling body 2 and the upper turning body 3 constitute a vehicle body of the present invention.

The upper swivel body 3 is provided on the swivel frame 5 forming the support structure, the counterweight 6 provided on the rear end side of the swivel frame 5 to balance the weight with the working device 4, and the front left side of the swivel frame 5. It is configured to include a cab 7 on which the operator is boarded, and a building cover 8 provided on the front side of the counterweight 6 and accommodating on-board equipment such as an engine 9 and an exhaust gas aftertreatment device 24, which will be described later.

As shown in FIG. 5, the swivel frame 5 is erected on a bottom plate 5A made of a thick steel plate extending in the front and rear directions and the bottom plate 5A, and has front and rear at predetermined intervals in the left and right directions. The left vertical plate 5B and the right vertical plate 5C extending in the direction, and the left side frame 5D and the right side frame 5E extending in the front and rear directions arranged at intervals in the left and right directions of the vertical plates 5B and 5C. , The bottom plate 5A, and a plurality of overhanging beams 5F that project from the vertical plates 5B and 5C in the left and right directions and support the left and right side frames 5D and 5E at the tip thereof. Of the plurality of overhanging beams 5F, the post-processing device pedestals 15 described later are attached to the front and rear overhanging beams 5F1 and 5F2 located on the right rear side.

The engine 9 is mounted on the swivel frame 5 in a horizontal position which is located on the front side of the counterweight 6 and extends in the left and right directions of the upper swivel body 3. As shown in FIGS. 2 to 4, a cooling fan 9A for supplying cooling air to the heat exchanger 11 described later is provided on the left side of the engine 9. On the other hand, a hydraulic pump 12, which will be described later, is provided on the right side of the engine 9. Further, a turbocharger 10 described later, which is connected to the exhaust manifold 9B, is provided on the upper portion of the front side of the engine 9. The engine 9 is supported by the swivel frame 5 in a vibration-proof state via, for example, four vibration-proof mounts 9C (only two are shown in FIG. 4).

The supercharger 10 (turbocharger) is located on the front side of the engine 9, for example, and is connected to the exhaust manifold 9B, and the exhaust port 10A opens toward the left and right sides of the upper swing body 3. Here, the exhaust port 10A of the supercharger 10 discharges the exhaust gas from the engine 9, and is upward and downward above the lower end of the cylinder 26 of the first exhaust gas aftertreatment device 25, which will be described later. It is provided at the position. An exhaust pipe 35 for guiding the exhaust gas to the exhaust gas aftertreatment device 24 (first exhaust gas aftertreatment device 25) is connected to the exhaust port 10A.

The heat exchanger 11 is arranged on the left side of the engine 9. The heat exchanger 11 is provided facing the cooling fan 9A of the engine 9. The heat exchanger 11 is composed of, for example, a radiator for cooling engine cooling water, an oil cooler for cooling hydraulic oil, an intercooler for cooling air sucked by the engine 9, and the like.

The hydraulic pump 12 is provided on the right side of the engine 9. The hydraulic pump 12 is driven by the engine 9 to discharge the hydraulic oil supplied from the hydraulic oil tank 13, which will be described later, toward the control valve device (not shown) as pressure oil.

The hydraulic oil tank 13 is located on the front side of the hydraulic pump 12 and is provided on the right side of the swivel frame 5. The hydraulic oil tank 13 stores hydraulic oil for driving an actuator provided in the lower traveling body 2, the working device 4, and the like. On the other hand, the fuel tank 14 is located on the front side of the hydraulic oil tank 13 and is provided on the swivel frame 5.

The post-processing device pedestal 15 is provided on the overhanging beams 5F1 and 5F2 in front of and behind the swivel frame 5 with the hydraulic pump 12 straddling the front and rear directions. The aftertreatment device stand 15 is for mounting the exhaust gas aftertreatment device 24, which will be described later. The post-processing device stand 15 includes a front leg portion 16, a rear leg portion 17, an auxiliary leg portion 18, and a post-processing device mounting frame 19.

The front leg portion 16 is located on the front side of the hydraulic pump 12 and rises from the swivel frame 5. The front leg portion 16 is mounted on an overhang beam 5F1 provided on the front side in the front and rear directions on the right rear side of the swivel frame 5. The height dimension of the front leg portion 16 is larger than the height dimension of the hydraulic pump 12. The front leg portion 16 includes a lower front leg portion 16A rising from the overhanging beam 5F1 and an upper front leg portion 16B rising from above the lower front leg portion 16A.

The rear leg portion 17 is located on the rear side of the hydraulic pump 12 and rises from the swivel frame 5. That is, the rear leg portion 17 faces the front and rear directions with the front leg portion 16 and the hydraulic pump 12 interposed therebetween. The rear leg portion 17 is attached to an overhang beam 5F2 provided on the rear right side of the swivel frame 5 on the rear side in the front and rear directions. The height dimension of the rear leg portion 17 is larger than the height dimension of the hydraulic pump 12. The rear leg portion 17 is composed of a lower rear leg portion 17A rising from the overhanging beam 5F2 and an upper rear leg portion 17B rising from above the lower rear leg portion 17A.

The auxiliary leg portion 18 is located between the lower front leg portion 16A and the right vertical plate 5C and rises from the swivel frame 5. The lower end side of the auxiliary leg portion 18 is attached to the overhanging beam 5F1 on the left side of the lower front leg portion 16A, and the upper end side is attached to the post-processing device mounting frame 19. The front leg portion 16, the rear leg portion 17, and the auxiliary leg portion 18 support the exhaust gas aftertreatment device 24 attached to the posttreatment device mounting frame 19 described later.

The aftertreatment device mounting frame 19 is located above the hydraulic pump 12 and connects the upper end positions of the upper front leg portion 16B and the upper rear leg portion 17B. The aftertreatment device mounting frame 19 is formed as a box-shaped body including a left side plate 19A, an upper plate 19B, a right side plate 19C, and a lower plate 19D, and is a first exhaust gas aftertreatment device 25 and a second exhaust gas described later. A gas aftertreatment device 30 is attached.

The left side plate 19A of the post-processing device mounting frame 19 is located on the engine 9 side and extends vertically between the upper front leg portion 16B and the upper rear leg portion 17B. A first exhaust gas aftertreatment device 25, which will be described later, is attached to the left side plate 19A by using a plurality of bolts 20 (only two are shown in FIGS. 5 to 7). On the front side (upper front leg portion 16B side) of the left side plate 19A, an inflow port insertion hole 19A1 penetrating in the plate thickness direction (left and right directions) is provided. The inflow port insertion hole 19A1 is formed at a position corresponding to the inflow port 26A of the first exhaust gas aftertreatment device 25, which will be described later, and is an inflow port 26A protruding from the cylinder 26 of the first exhaust gas aftertreatment device 25. Is inserted.

The upper plate 19B of the aftertreatment device mounting frame 19 extends horizontally from the upper end of the left side plate 19A. The upper plate 19B is bent in a direction away from the engine 9 from the upper end of the left side plate 19A. A second exhaust gas aftertreatment device 30, which will be described later, is attached to the upper plate 19B via the attachment plate 21 by using a plurality of (for example, two) bolts 22.

The right side plate 19C of the aftertreatment device mounting frame 19 extends downward from the right end of the upper plate 19B. That is, the right side plate 19C faces the left side plate 19A in the left and right directions. The right side plate 19C has an exhaust pipe insertion hole 19C1 formed at a position corresponding to the inflow port insertion hole 19A1 of the left side plate 19A. A bent pipe line 37 of an exhaust pipe 35, which will be described later, is inserted into the exhaust pipe insertion hole 19C1. Further, the exhaust pipe insertion hole 19C1 can allow a tool or the like to be inserted when the exhaust gas outflow side of the bent pipe line 37 is connected to the inflow port 26A of the first exhaust gas aftertreatment device 25.

A cover member 39, which will be described later, is attached to the right side plate 19C at a position corresponding to the exhaust pipe insertion hole 19C1. Further, the right side plate 19C is formed with a plurality of (for example, two) working openings 19C2. The working opening 19C2 is, for example, a tool for fastening bolts 20 and 22 for attaching the first exhaust gas aftertreatment device 25 and the second exhaust gas aftertreatment device 30 to the aftertreatment device mounting frame 19. Is inserted.

The lower plate 19D of the aftertreatment device mounting frame 19 connects the lower end of the left side plate 19A and the lower end of the right side plate 19C. That is, the lower plate 19D faces the upper plate 19B in the upward and downward directions. A firewall 23 extending downward is attached to the lower plate 19D (see FIG. 7). The firewall 23 is a partition member that partitions the space on the engine side where the engine 9, the exhaust gas aftertreatment device 24, and the like are arranged and the space on the pump side where the hydraulic pump 12 is arranged. The firewall 23 prevents the leaked hydraulic oil from scattering to the engine 9 side even if the hydraulic oil leaks around the hydraulic pump 12, for example.

Next, the exhaust gas aftertreatment device 24 that purifies the exhaust gas discharged from the engine 9 will be described.

The exhaust gas aftertreatment device 24 is connected to the exhaust gas outflow side (outlet side) of the exhaust gas pipe 35, which will be described later, connected to the exhaust port 10A of the engine 9, and is attached to the aftertreatment device stand 15. The exhaust gas aftertreatment device 24 is composed of a first exhaust gas aftertreatment device 25, a connection pipe 28, and a second exhaust gas aftertreatment device 30.

The first exhaust gas aftertreatment device 25 is arranged on the upper side of the hydraulic pump 12 in a state of being attached to the left side plate 19A of the aftertreatment device mounting frame 19. The first exhaust gas aftertreatment device 25 is provided on the exhaust gas outflow side of the exhaust pipe 35, which will be described later. The first exhaust gas aftertreatment device 25 includes a long cylindrical cylinder 26 extending in the front and rear directions, and an oxidation catalyst 27 arranged in the cylinder 26.

The tubular body 26 of the first exhaust gas aftertreatment device 25 is formed as a closed container with both ends closed. As shown in FIGS. 4 and 8, the front side portion on the upstream side of the cylinder body 26 sandwiches the axis lines O1-O1 of the cylinder body 26 from the opposite side of the engine 9 toward the radial outside of the cylinder body 26. A protruding tubular inflow port 26A is provided. The inflow port 26A constitutes the exhaust gas inflow side of the first exhaust gas aftertreatment device 25, and is connected to the bent pipe line 37 of the exhaust pipe 35 described later. On the other hand, on the outer peripheral side of the cylinder 26, a bracket 26B for attaching the first exhaust gas aftertreatment device 25 to the aftertreatment device mounting frame 19 is provided.

As shown in FIG. 10, the oxidation catalyst 27 constitutes one of the processing members for purifying the exhaust gas, and is made of, for example, a ceramic cell-shaped cylinder, and has a large number of through holes in the axial direction thereof. It is formed and the inner surface is coated with a precious metal or the like. Then, the oxidation catalyst 27 oxidizes and removes carbon monoxide (CO), hydrocarbons (HC) and the like contained in the exhaust gas by passing the exhaust gas through the through holes under a predetermined temperature. In addition, particulate matter (PM) is also burned and removed as needed.

The connection pipe 28 connects between the first exhaust gas aftertreatment device 25 and the second exhaust gas aftertreatment device 30, which will be described later. As shown in FIGS. 8 and 9, the connecting pipe 28 is curved in a U shape with the exhaust gas inflow side connected to the rear end (exhaust gas outflow side) of the cylinder 26 of the first exhaust gas aftertreatment device 25. The curved portion 28A and the upper side of the cylinder 26 extend from the curved portion 28A in the front and rear directions in parallel with the cylinder 26, and the exhaust gas outflow side is on the front side of the cylinder 31 of the second exhaust gas aftertreatment device 30. It is composed of an extension portion 28B to be connected.

As shown in FIG. 9, the curved portion 28A of the connecting pipe 28 is located on the front side (inflow port 26A side) of the rear end of the tubular body 31 of the second exhaust gas aftertreatment device 30. That is, the curved portion 28A is curved so as not to protrude from the rear end of the tubular body 31 of the second exhaust gas aftertreatment device 30. Further, as shown in FIG. 8, the extending portion 28B of the connecting pipe 28 has the width dimension and the height dimension of the exhaust gas aftertreatment device 24 in the lateral direction (left and right directions) as small as possible. It is arranged on the upper side of the first exhaust gas aftertreatment device 25 and on the lower left side of the second exhaust gas aftertreatment device 30.

The urea water injection nozzle 29 is attached to the upstream side of the connecting pipe 28 in the exhaust gas flow direction. The urea water injection nozzle 29 is attached to the rear end side of the extending portion 28B of the connecting pipe 28, and is connected to the urea water tank for storing the urea aqueous solution via a pump (none of which is shown). The urea water injection nozzle 29 injects an aqueous urea solution toward the exhaust gas flowing in the connecting pipe 28.

The second exhaust gas aftertreatment device 30 is arranged above the hydraulic pump 12 in a state of being attached to the upper plate 19B of the aftertreatment device mounting frame 19. That is, the second exhaust gas aftertreatment device 30 is arranged on the diagonally upper right side of the first exhaust gas aftertreatment device 25. The second exhaust gas aftertreatment device 30 is connected to the exhaust gas outflow side of the connecting pipe 28, and is long and extends in the front and rear directions in parallel with the cylinder 26 of the first exhaust gas aftertreatment device 25. A cylindrical cylinder 31, a selective reduction catalyst 32 which is arranged in the cylinder 31 and selectively reduces nitrogen oxides (NOx) with ammonia to decompose them into water and nitrogen, and a selective reduction catalyst 32. An oxidation catalyst 33 which is arranged on the downstream side and oxidizes residual ammonia remaining after reducing nitrogen oxides with the selective reduction catalyst 32 and separates it into nitrogen and water, and an oxidation catalyst 33 which is arranged on the downstream side of the oxidation catalyst 33 and is a cylinder 31. It is configured to include a tail tube 34 protruding upward from the surface.

The cylinder 31 of the second exhaust gas aftertreatment device 30 is formed as a closed container with both ends closed, and is a cylinder slightly longer than the cylinder 26 of the first exhaust gas aftertreatment device 25. An extension portion 28B of the connecting pipe 28 is connected to the side surface on the engine 9 side to the front side portion on the upstream side of the cylinder 31. On the other hand, on the outer peripheral side of the tubular body 31, a bracket 31A for attaching the second exhaust gas aftertreatment device 30 to the aftertreatment device mounting frame 19 via the mounting plate 21 is provided.

As shown in FIG. 9, the axis O2-O2 of the cylinder 31 of the second exhaust gas aftertreatment device 30 is parallel to the axis O1-O1 of the cylinder 26 of the first exhaust gas aftertreatment device 25. There is. Further, as shown in FIG. 8, the axis O2-O2 of the cylinder 31 of the second exhaust gas aftertreatment device 30 is in a state where the distance L1 to the axis O1-O1 of the cylinder 26 is as small as possible. , Is deviated to the right by an angle α with respect to the vertical line AA passing through the axis lines O1-O1 of the tubular body 26. This angle α makes the width L2 formed by the cylinder 26 of the first exhaust gas aftertreatment device 25 and the cylinder 31 of the second exhaust gas aftertreatment device 30 as small as possible, and the connecting pipe 28. Is set so that it does not protrude significantly toward the engine 9.

That is, the cylinder 31 of the second exhaust gas aftertreatment device 30 is arranged above the cylinder 26 of the first exhaust gas aftertreatment device 25 and shifted to the right side frame 5E side (right side). There is. Further, the first exhaust gas aftertreatment device 25 and the second exhaust gas aftertreatment device 30 are arranged so that a part thereof overlaps in the upward and downward directions when viewed from above. As a result, the width L2 of the first exhaust gas aftertreatment device 25 and the second exhaust gas aftertreatment device 30 is made as small as possible, so that the width dimension of the aftertreatment device pedestal 15 is made small. It can be made compact. As a result, an empty space can be secured in the space on the pump side where the exhaust gas aftertreatment device 24 and the hydraulic pump 12 are arranged, so that the empty space can be effectively utilized.

As shown in FIG. 10, the selective reduction catalyst 32 is made of, for example, a ceramic cell-shaped cylinder, and a large number of through holes are formed in the axial direction thereof, and the inner surface thereof is coated with a precious metal. The selective reduction catalyst 32 selectively reduces nitrogen oxides (NOx) contained in the exhaust gas discharged from the engine 9 by ammonia generated from an aqueous urea solution, and decomposes them into nitrogen and water. ..

Similar to the above-mentioned oxidation catalyst 27, the oxidation catalyst 33 is made of a cell-shaped cylinder made of ceramics, and a large number of through holes are formed in the axial direction thereof, and the inner surface thereof is coated with a precious metal. As a result, the oxidation catalyst 33 oxidizes the residual ammonia remaining after reducing the nitrogen oxide with the selective reduction catalyst 32 and separates it into nitrogen and water.

The tail tube 34 is located at the rear side portion on the downstream side of the tubular body 31 (downstream side of the oxidation catalyst 33), one end (lower end) in the length direction is inserted into the tubular body 31, and the other end is the tubular body. It protrudes radially upward from 31. A large number of through holes are provided on the lower end side of the tail pipe 34 that has entered the cylinder 31, and the exhaust gas can pass through each of these through holes to reduce (silence) the exhaust noise.

Next, the exhaust pipe 35 that guides the exhaust gas discharged from the engine 9 to the exhaust gas aftertreatment device 24 will be described.

In the exhaust pipe 35, the exhaust gas inflow side (upstream side) is connected to the exhaust port 10A of the supercharger 10 constituting the engine 9, and the exhaust gas outflow side (downstream side) is connected to the exhaust gas aftertreatment device 24. There is. The exhaust pipe 35 is formed as a metal pipeline, and guides the high-temperature exhaust gas discharged from the engine 9 to the first exhaust gas aftertreatment device 25. The exhaust pipe 35 includes a horizontal pipe line 36 and a bent pipe line 37.

The horizontal pipeline 36 of the exhaust pipe 35 extends from the exhaust port 10A of the engine 9 along the length direction (left, right direction) of the engine 9 and is below the cylinder 26 forming the first exhaust gas aftertreatment device 25. In a direction (left, right) orthogonal to the axis lines O1-O1 of the cylinder 26. In this case, the horizontal pipeline 36 extends below the inflow port 26A formed in the tubular body 26 of the first exhaust gas aftertreatment device 25 in the left and right directions of the swivel frame 5.

The horizontal pipeline 36 is inclined downward from the upper horizontal pipeline portion 36A extending in the horizontal direction from the exhaust port 10A and the tip side of the upper horizontal pipeline portion 36A toward the lower side of the first exhaust gas aftertreatment device 25. It is composed of an inclined pipeline portion 36B and a lower horizontal pipeline portion 36C located below the first exhaust gas aftertreatment device 25 and extending from the tip end side of the inclined pipeline portion 36B toward the bent pipeline portion 37. There is. That is, the horizontal pipeline 36 is formed in a crank shape by the upper horizontal pipeline portion 36A, the inclined pipeline portion 36B, and the lower horizontal pipeline portion 36C. In this case, as shown in FIG. 4, the lower horizontal pipeline portion 36C is located between the hydraulic pump 12 and the first exhaust gas aftertreatment device 25 on the rear side of the front leg portion 16 of the aftertreatment device pedestal 15. ing.

The bent pipe 37 of the exhaust pipe 35 bends upward from the tip side of the lower horizontal pipe portion 36C of the horizontal pipe 36, and the inflow port 26A (exhaust gas inflow side) of the first exhaust gas aftertreatment device 25 )It is connected to the. That is, the bent pipeline 37 is bent in a U shape from the lower horizontal pipeline portion 36C toward the inflow port 26A of the tubular body 26.

As shown in FIGS. 4 and 7, the bending pipe 37 bends upward from the lower horizontal pipe portion 36C, and has an exhaust pipe insertion hole 19C1 formed in the right side plate 19C of the aftertreatment device mounting frame 19. It is inserted and connected to the inflow port 26A of the tubular body 26. In this case, the intermediate portion of the bending pipeline 37 is a protruding portion 37A that protrudes from the right side plate 19C of the post-processing device mounting frame 19 of the post-processing device stand 15 toward the opposite side (right side) of the engine 9. ..

The bellows pipe 38 is provided in the lower horizontal pipe portion 36C of the horizontal pipe 36. The bellows pipe 38 is formed as a bellows-shaped metal cylinder having a larger hole diameter than, for example, the lower horizontal pipe portion 36C, and causes a relative displacement (vibration) between the engine 9 and the first exhaust gas aftertreatment device 25. Absorb. That is, since the vibration systems of the exhaust gas aftertreatment device 24 and the engine 9 mounted on the aftertreatment device pedestal 15 provided on the swivel frame 5 are different, the relative displacements between the two are generated by the different vibration systems. Is absorbed by the bending deformation of the bellows tube 38.

Here, the inflow port 26A of the cylinder body 26 of the first exhaust gas aftertreatment device 25 is provided on the side opposite to the engine 9 with the axis lines O1-O1 of the cylinder body 26 interposed therebetween. As a result, the exhaust pipe 35 can form the lower horizontal pipeline portion 36C in a long length. By providing the lower horizontal pipeline portion 36C with a long bellows pipe 38, the relative displacement (vibration) between the engine 9 and the first exhaust gas aftertreatment device 25 can be efficiently absorbed. ..

Further, as shown in FIG. 8, the bellows pipe 38 is housed in the width L2 formed by the first exhaust gas aftertreatment device 25 and the second exhaust gas aftertreatment device 30. That is, the first exhaust gas aftertreatment device 25, the second exhaust gas aftertreatment device 30, and the bellows pipe 38 are, in order from the bottom in the upward and downward directions, the bellows pipe 38 and the first exhaust gas aftertreatment device 25. , The second exhaust gas aftertreatment device 30 is superimposed in this order.

Further, as shown in FIG. 9, the bellows pipe 38 is housed in the vertical dimension L3 formed by the first exhaust gas aftertreatment device 25 and the second exhaust gas aftertreatment device 30. As a result, the lateral (longitudinal) dimension and the vertical dimension of the first exhaust gas aftertreatment device 25, the second exhaust gas aftertreatment device 30, and the bellows pipe 38 are suppressed. , These can be compactly arranged on the swivel frame 5.

The cover member 39 is provided at a position corresponding to the exhaust pipe insertion hole 19C1 formed in the right side plate 19C of the aftertreatment device mounting frame 19. The cover member 39 extends along the bent pipe line 37 and the lower horizontal pipe line portion 36C between the exhaust pipe insertion hole 19C1 formed in the right side plate 19C of the aftertreatment device mounting frame 19 and the fire wall 23, and is hydraulically pressured. It is a partition member that partitions between the pump 12 and the bent pipeline 37 and between the hydraulic pump 12 and the lower horizontal pipeline portion 36C.

As shown in FIG. 7, the cover member 39 projects from the mounting plate portion 39A mounted on the right side plate 19C of the post-processing device mounting frame 19 and the mounting plate portion 39A toward the right side (the side opposite to the engine 9). Includes a bending line covering plate 39B extending along the bending line 37 and a lower horizontal line covering plate 39C extending from the bending line covering board 39B to the fire wall 23 along the lower horizontal line 36C. Is formed of.

The cover member 39 is attached to the aftertreatment device mounting frame 19 by bolts 40 in a state where the mounting plate portion 39A is in contact with the right side plate 19C at a position corresponding to the exhaust pipe insertion hole 19C1. Further, the cover member 39 is formed with a firewall contact plate portion 39D along the firewall 23 at the tip and upper ends of the lower horizontal pipeline covering plate portion 39C. The cover member 39 is attached to the firewall 23 by other bolts (not shown) in a state where the firewall contact plate portion 39D is in contact with the firewall.

As shown in FIGS. 4 and 6, the bending pipe covering plate portion 39B of the cover member 39 covers the outer peripheral side of the protruding portion 37A of the bending pipe 37. On the other hand, the lower horizontal pipeline covering plate portion 39C of the cover member 39 covers the outer peripheral side of the bellows pipe 38 provided in the lower horizontal pipeline portion 36C and the lower horizontal pipeline portion 36C. As a result, the cover member 39 shields between the hydraulic pump 12, the lower horizontal pipeline portion 36C, and the bending pipeline 37, so that even if hydraulic oil leaks around the hydraulic pump 12, for example, The leaked hydraulic oil is prevented from being scattered to the lower horizontal pipe section 36C and the bending pipe line 37 of the exhaust pipe 35.

The hydraulic excavator 1 according to the present embodiment has the above-mentioned configuration, and its operation will be described next.

First, the operator gets on the cab 7 and operates the engine 9. Then, the operator can drive the hydraulic excavator 1 by operating the traveling operation lever (not shown) arranged in the cab 7, and operate the working operation lever (not shown). By doing so, it is possible to perform excavation work of earth and sand using the work device 4.

Here, when the engine 9 is in operation, the exhaust gas discharged from the engine 9 is introduced into the first exhaust gas aftertreatment device 25 from the exhaust port 10A via the exhaust pipe 35. Then, as shown by an arrow in FIG. 10, the exhaust gas passes from the first exhaust gas aftertreatment device 25 through the second exhaust gas aftertreatment device 30 via the connecting pipe 28, and passes through the tail pipe 34 into the atmosphere. Is discharged to.

In this case, carbon monoxide (CO), hydrocarbon (HC) and the like contained in the exhaust gas are oxidized and removed by the oxidation catalyst 27 provided in the first exhaust gas aftertreatment device 25. In addition, particulate matter (PM) is burned and removed as needed. On the other hand, in the connecting pipe 28, urea water is injected from the urea water injection nozzle 29 toward the exhaust gas, and in the second exhaust gas aftertreatment device 30, nitrogen oxides are decomposed into nitrogen and water by the selective reduction catalyst 32. Will be done. Further, the oxidation catalyst 33 oxidizes the residual ammonia and separates it into nitrogen and water, so that the sufficiently purified exhaust gas can be discharged to the atmosphere.

By the way, in the above-mentioned prior art, the first exhaust gas aftertreatment device, the second exhaust gas aftertreatment device, and the exhaust pipe are arranged in parallel in the horizontal direction (horizontal direction). Further, the exhaust pipe is provided with a bellows pipe having a predetermined length dimension in order to absorb a relative displacement amount with respect to vibration between the engine and the exhaust gas aftertreatment device. Therefore, in order to dispose the exhaust gas aftertreatment device, the exhaust pipe, and the bellows pipe, a large space may be required in the front, rear, left, and right directions of the vehicle body.

Therefore, in the present embodiment, the first exhaust gas aftertreatment device 25, the second exhaust gas aftertreatment device 30, and the exhaust pipe 35 are arranged so as to be superimposed in the upward and downward directions. Specifically, as shown in FIG. 8, the second exhaust gas aftertreatment device 30 located on the upper side has the axis lines O1-O1 and the second exhaust of the cylinder body 26 of the first exhaust gas aftertreatment device 25. With the distance L1 between the axis O2 and the axis O2 of the cylinder 31 of the gas aftertreatment device 30 as small as possible, the angle α with respect to the vertical line AA passing through the axis O1-O1 of the cylinder 26. It is arranged in a staggered position. By horizontally shifting the first exhaust gas aftertreatment device 25 and the second exhaust gas aftertreatment device 30, the first exhaust gas aftertreatment device 25 and the second exhaust gas aftertreatment device 30 are separated from each other. The connecting pipe 28 is efficiently arranged between them.

Then, as shown in FIGS. 8 and 9, the lower horizontal pipeline portion 36C constituting the horizontal pipeline 36 of the exhaust pipe 35 is arranged below the first exhaust gas aftertreatment device 25. That is, the exhaust pipe 35 is within the vertical dimension L3 (length dimension in the axial direction) of the exhaust gas aftertreatment device 24 formed by the first exhaust gas aftertreatment device 25 and the second exhaust gas aftertreatment device 30. It is compactly housed in. As a result, the space for arranging the exhaust gas aftertreatment device 24 and the exhaust pipe 35 can be reduced.

Further, the lower horizontal pipeline portion 36C is provided with a bellows pipe 38 that absorbs the relative displacement between the engine 9 and the first exhaust gas aftertreatment device 25. As shown in FIG. 8, the bellows pipe 38 is compactly housed in the width L2 formed by the first exhaust gas aftertreatment device 25 and the second exhaust gas aftertreatment device 30. As a result, the space for arranging the exhaust gas aftertreatment device 24 and the bellows pipe 38 provided in the exhaust pipe 35 can be reduced.

Further, a part of the bent pipe line 37 of the exhaust pipe 35 protrudes from the right side plate 19C constituting the post-treatment device mounting frame 19 of the post-treatment device pedestal 15 as a protruding portion 37A. The protruding portion 37A of the bent pipe line 37 is covered with a bent pipe line covering plate portion 39B of a cover member 39 that shields between the bending pipe line 37 and the hydraulic pump 12. Thereby, for example, even if the hydraulic oil leaks around the hydraulic pump 12, it is possible to prevent the leaked hydraulic oil from being scattered in the bending pipe line 37. On the other hand, the lower horizontal pipeline covering plate portion 39C of the cover member 39 covers the lower horizontal pipeline portion 36C and the bellows pipe 38 of the exhaust pipe 35. Thereby, for example, even if the hydraulic oil leaks around the hydraulic pump 12, it is possible to prevent the leaked hydraulic oil from scattering to the lower horizontal pipeline portion 36C and the bellows pipe 38.

Further, the width of the aftertreatment device mounting frame 19 is reduced by making the width L2 formed by the first exhaust gas aftertreatment device 25 and the second exhaust gas aftertreatment device 30 as small as possible. Can be done. As a result, a part (protruding portion 37A) of the bent pipeline 37 protrudes from the post-processing device mounting frame 19, but by covering the protruding portion 37A with the cover member 39, the cover member 39 and the rear leg portion 17 are formed. The space formed between the two can be effectively utilized. That is, the width of the post-processing device mounting frame 19 becomes large when it matches the protruding portion 37A of the bending pipe line 37, but the width of the post-processing device mounting frame 19 is made as small as possible so that the bending pipe line 37 protrudes. By covering only the portion 37A with the cover member 39, a space can be secured behind the cover member 39.

Thus, the construction machine according to the present embodiment has a self-propelled vehicle body (lower traveling body 2, upper swivel body 3), an engine 9 mounted on the vehicle body, and an exhaust pipe connected to an exhaust port 10A of the engine 9. 35, a first exhaust gas aftertreatment device 25 composed of a cylinder 26 provided on the exhaust gas outflow side of the exhaust pipe 35, and an exhaust gas outflow side of the first exhaust gas aftertreatment device 25 are connected. The connection pipe 28 and the second exhaust gas aftertreatment device 30 composed of a cylinder 31 provided on the exhaust gas outflow side of the connection pipe 28 are provided, and the exhaust gas of the first exhaust gas aftertreatment device 25 is provided. The gas inflow side (inflow port 26A) is provided on the opposite side of the engine 9 with the axis lines O1-O1 of the cylinder 26 forming the first exhaust gas aftertreatment device 25 interposed therebetween, and the second exhaust gas is provided. The gas aftertreatment device 30 is arranged above the first exhaust gas aftertreatment device 25 so as to overlap the first exhaust gas aftertreatment device 25 in the upward and downward directions.

The feature of the present embodiment is that the exhaust pipe 35 extends from the exhaust port 10A of the engine 9 along the length direction of the engine 9 to form the first exhaust gas aftertreatment device 25. A cross-pipeline 36 that crosses the lower part of the body 26 in a direction orthogonal to the axis O1-O1 of the cylinder 26, and the first exhaust gas aftertreatment device that bends upward from the tip end side of the cross-pipeline 36. It is composed of a bent pipe line 37 connected to the exhaust gas inflow side (inflow port 26A) of 25.

Further, the horizontal pipe 36 of the exhaust pipe 35 has an upper horizontal pipe portion 36A extending in the horizontal direction from the exhaust port 10A and the first exhaust gas post-treatment from the tip side of the upper horizontal pipe portion 36A. An inclined pipeline portion 36B that inclines downward toward the lower side of the device 25, and a bent pipeline portion 37 located below the first exhaust gas aftertreatment device 25 from the tip end side of the inclined pipeline portion 36B. It is composed of a lower horizontal pipeline portion 36C extending toward the direction.

Further, a bellows pipe 38 for absorbing the relative displacement between the engine 9 and the first exhaust gas aftertreatment device 25 is provided in the lower horizontal pipe portion 36C of the horizontal pipe 36. Further, the bellows pipe 38 is housed in the width L2 formed by the first exhaust gas aftertreatment device 25 and the second exhaust gas aftertreatment device 30.

Further, one side of the length direction of the engine 9 where the first exhaust gas aftertreatment device 25 and the second exhaust gas aftertreatment device 30 are provided is driven by the engine 9. A hydraulic pump 12 is provided, and the first exhaust gas aftertreatment device 25 and the second exhaust gas aftertreatment device 30 straddle the hydraulic pump 12 in the front and rear directions of the vehicle body. The bending line 37 is attached to the post-processing device pedestal 15 provided in the above, and the bending pipeline 37 protrudes from the after-treatment device pedestal 15 toward the side opposite to the engine 9, and the protruding portion 37A is a cover member 39. It is covered.

In the above-described embodiment, the exhaust port 10A of the engine 9 is located above the lower end of the first exhaust gas aftertreatment device 25, and the horizontal pipeline 36 of the exhaust pipe 35 is set to the upper horizontal pipeline portion 36A. The case where the structure is composed of the inclined pipeline portion 36B and the lower horizontal pipeline portion 36C has been described as an example. However, the present invention is not limited to this, and for example, when the exhaust port 10A of the engine 9 is located below the lower end of the first exhaust gas aftertreatment device 25, the horizontal pipeline 36 is the exhaust port of the engine. It may be formed in a straight line from the to the bent pipe line 37.

Further, in the above-described embodiment, the case where the horizontal pipe 36 is configured by the inclined pipe portion 36B inclined between the upper horizontal pipe portion 36A and the lower horizontal pipe portion 36C has been described as an example. However, the present invention is not limited to this, and for example, the upper horizontal pipeline portion 36A and the lower horizontal pipeline portion 36C may be connected by a pipeline portion extending in the vertical direction (up and down).

Further, in the above-described embodiment, the case where only the oxidation catalyst 27 is provided in the cylinder 26 of the first exhaust gas aftertreatment device 25 has been described as an example. However, the present invention is not limited to this, and for example, a particulate matter removal filter (DPF) may be provided on the downstream side of the oxidation catalyst 27 in the cylinder 26 of the first exhaust gas aftertreatment device 25. This particulate matter removal filter purifies the exhaust gas by collecting the particulate matter (PM) in the exhaust gas discharged from the engine, burning it, and removing it.

Further, in the above-described embodiment, the hydraulic excavator 1 provided with the crawler-type lower traveling body 2 has been described as an example of the construction machine. However, the present invention is not limited to this, and may be applied to, for example, a hydraulic excavator provided with a wheel-type lower traveling body. Besides that, it can be widely applied to other construction machines such as wheel loaders, dump trucks and hydraulic cranes.

1 Hydraulic excavator (construction machinery)
2 Lower vehicle (body)
3 Upper swivel body (body)
9 Engine 10 Supercharger 10A Exhaust port 12 Hydraulic pump 15 Post-treatment device stand 25 First exhaust gas after-treatment device 26 Cylindrical body 26A Inlet 28 Connection pipe 30 Second exhaust gas after-treatment device 31 Cylindrical body 35 Exhaust pipe 36 Horizontal pipe 36A Upper horizontal pipe 36B Inclined pipe 36C Lower horizontal pipe 37 Bending pipe 38 Bellows pipe 39 Cover member O1-O1 Axis of cylinder 26 L2 Width

Claims (4)

A self-propelled vehicle body, an engine mounted on the vehicle body, an aftertreatment device mount provided on the vehicle body, an exhaust pipe connected to an exhaust port of the engine, and an exhaust gas outflow side of the exhaust pipe. A first exhaust gas aftertreatment device composed of a provided tubular body, a connection pipe connected to the exhaust gas outflow side of the first exhaust gas aftertreatment device, and a connection pipe provided on the exhaust gas outflow side of the connection pipe. It is equipped with a second exhaust gas aftertreatment device consisting of a cylinder.
The first exhaust gas aftertreatment device and the second exhaust gas aftertreatment device are attached to the aftertreatment device stand.
The inlet of the first exhaust gas aftertreatment device to which the exhaust gas outflow side of the exhaust pipe is connected is opposite to the engine with the axis of the cylinder forming the first exhaust gas aftertreatment device. Provided on the side,
In a construction machine in which the second exhaust gas aftertreatment device is arranged above the first exhaust gas aftertreatment device so as to overlap the first exhaust gas aftertreatment device in the upward and downward directions.
The exhaust pipe bends upward from the exhaust port of the engine to a horizontal pipe line that crosses the lower part of the cylinder forming the first exhaust gas aftertreatment device and from the tip end side of the horizontal pipe line. It is composed of a bent pipe line connected to the inlet of the first exhaust gas aftertreatment device.
The intermediate portion of the bent pipeline protrudes from the aftertreatment device mount toward the side opposite to the engine.
The horizontal pipeline is provided with a bellows pipe that absorbs the relative displacement between the engine and the first exhaust gas aftertreatment device.
The bellows pipe, the first exhaust gas aftertreatment device, and the second exhaust gas aftertreatment device are, in order from the bottom in the upward and downward directions, the bellows pipe, the first exhaust gas aftertreatment device, and the said. The bellows pipes are arranged so as to be overlapped in the order of the second exhaust gas aftertreatment device, and the bellows pipe is within the width formed by the first exhaust gas aftertreatment device and the second exhaust gas aftertreatment device. A construction machine characterized by being fitted and placed. The horizontal pipeline of the exhaust pipe has an upper horizontal pipeline portion extending in the horizontal direction from the exhaust port and a downward direction from the tip end side of the upper horizontal pipeline portion toward the lower side of the first exhaust gas aftertreatment device. It is composed of an inclined pipeline portion that is inclined to the surface and a lower horizontal pipeline portion that is located below the first exhaust gas aftertreatment device and extends from the tip end side of the inclined pipeline portion toward the bent pipeline portion. The construction machine according to claim 1, wherein the construction machine is characterized by the above. The construction machine according to claim 2, wherein the bellows pipe is provided in the lower horizontal pipe portion of the horizontal pipe. The construction machine according to claim 1, wherein a protruding portion of the bent pipeline projecting from the post-treatment device gantry toward the side opposite to the engine is covered with a cover member.

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