JP7271745B2 - construction machinery - Google Patents

Description

TECHNICAL FIELD The present invention relates to a construction machine such as a hydraulic excavator having an exhaust gas post-treatment device in an exhaust pipe of an engine, for example.

In general, a hydraulic excavator as a construction machine includes a self-propelled undercarriage, an upper revolving body rotatably mounted on the undercarriage, and a tiltable upper revolving body provided on the front side of the upper revolving body. It consists of a work device. The upper revolving structure has a cab, a fuel tank, a hydraulic oil tank, etc. mounted on the front side of the revolving frame, and an engine, a hydraulic pump, etc. mounted on the rear side of the revolving frame.

Diesel engines are generally used as engines for hydraulic excavators. This diesel engine emits harmful substances such as particulate matter (PM) and nitrogen oxides (NOx). Therefore, the hydraulic excavator is provided with an exhaust gas post-treatment device for purifying the exhaust gas in the exhaust pipe of the engine. This exhaust gas post-treatment device includes a PM trapping device having a DPF (Diesel Particulate Filter) that traps particulate matter contained in the exhaust gas, and a NOx purification device that purifies nitrogen oxides (NOx) contained in the exhaust gas. device is known. Furthermore, as an exhaust gas post-treatment device, a silencer for reducing exhaust noise is also known (see, for example, Patent Document 1).

WO2014/196395

By the way, in the exhaust gas aftertreatment device described in the above-mentioned Patent Document 1, the first exhaust gas aftertreatment device, the second exhaust gas aftertreatment device, and the exhaust pipe are arranged in parallel in the horizontal direction (lateral direction). are arranged. A bellows pipe having a predetermined length is provided in the exhaust pipe in order to absorb relative displacement due to vibration between the engine and the exhaust aftertreatment device. Therefore, there is a possibility that a large space is required in the front, rear, left, and right directions of the vehicle body for arranging the exhaust gas aftertreatment device, the exhaust pipe, and the bellows pipe.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a construction machine in which an exhaust gas post-treatment device and an exhaust pipe are compactly arranged.

A construction machine according to the present invention comprises a self-propellable vehicle body, an engine mounted on the vehicle body, a post-processing device mount provided on the vehicle body, an exhaust pipe connected to an exhaust port of the engine, and the exhaust. A first exhaust gas aftertreatment device consisting of a cylindrical body provided on an exhaust gas outflow side of a 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 comprising a cylindrical body provided on an exhaust gas outflow side, wherein the first exhaust gas aftertreatment device and the second exhaust gas aftertreatment device The inflow port of the first exhaust gas aftertreatment device, which is attached to the device mount and connected to the exhaust gas outflow side of the exhaust pipe, is located in the cylindrical body forming the first exhaust gas aftertreatment device. The second exhaust gas aftertreatment device is provided on the opposite side of the engine with respect to the axis, and overlaps the first exhaust gas aftertreatment device in the upper and lower directions. It is placed above the device.

A feature of the present invention is that the exhaust pipe includes a horizontal pipe traversing from the exhaust port of the engine to the bottom of the cylinder forming the first exhaust aftertreatment device, and a tip of the horizontal pipe. and a bent pipeline that bends upward from the side and is connected to the inlet of the first exhaust gas aftertreatment device, and a midway portion of the curved pipeline extends from the aftertreatment device mount to the A bellows pipe that protrudes toward the side opposite to the engine and absorbs relative displacement between the engine and the first exhaust gas aftertreatment device is provided in the horizontal conduit, and the bellows The pipe, the first exhaust gas aftertreatment device, and the second exhaust gas aftertreatment device are arranged in this order from the bottom in the upward and downward direction: the bellows pipe, the first exhaust gas aftertreatment device, the second exhaust gas aftertreatment device. and the bellows pipe fits within the width formed by the first exhaust gas aftertreatment device and the second exhaust gas aftertreatment device. are placed.

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

1 is a front view showing a hydraulic excavator according to an embodiment of the present invention; FIG. FIG. 4 is a plan view showing the upper revolving structure with the cab, building cover, etc. omitted. FIG. 3 is an enlarged plan view showing the engine, the exhaust gas aftertreatment device, etc. in FIG. 2 ; FIG. 4 is a cross-sectional view of the engine, aftertreatment device mount, and exhaust gas aftertreatment device as viewed in the direction of arrows IV-IV in FIG. 3; FIG. 2 is a perspective view showing an aftertreatment device mount and an exhaust gas aftertreatment device mounted on a revolving frame; FIG. 2 is a perspective view showing an exhaust gas aftertreatment device attached to an aftertreatment device pedestal; FIG. 4 is an exploded perspective view showing a state in which a cover member is removed from the post-processing device pedestal; FIG. 5 is a side view showing an enlarged exhaust gas post-treatment device in FIG. 4 ; FIG. 9 is a front view of the exhaust gas aftertreatment device as viewed in the direction of arrows IX-IX in FIG. 8; FIG. 2 is a cross-sectional view schematically showing the internal structure of the exhaust aftertreatment device;

DESCRIPTION OF THE PREFERRED EMBODIMENTS A crawler hydraulic excavator will be exemplified below as a representative example of a construction machine according to an embodiment of the present invention, and will be described in detail with reference to the accompanying drawings.

A hydraulic excavator 1 shown in FIG. It is composed of a working device 4 which is provided on the front side so as to be able to be raised and lowered and which performs excavation work of earth and sand. The lower running body 2 and the upper revolving body 3 constitute the vehicle body of the present invention.

The upper revolving body 3 includes a revolving frame 5 that forms a support structure, a counterweight 6 that is provided on the rear end side of the revolving frame 5 and balances the weight of the work device 4 , and a counterweight 6 that is provided on the front left side of the revolving frame 5 . It comprises a cab 7 on which an operator rides, and a building cover 8 which is provided in front of the counterweight 6 and accommodates mounted equipment such as an engine 9 and an exhaust gas post-treatment device 24, which will be described later.

As shown in FIG. 5, the revolving frame 5 has a bottom plate 5A made of a thick steel plate or the like that extends in the front and rear directions, and is erected on the bottom plate 5A so that it is spaced forward and rearward at a predetermined distance in the left and right directions. A left vertical plate 5B and a right vertical plate 5C extending in the left and right directions, and a left side frame 5D and a right side frame 5E extending in the front and rear directions, which are arranged at intervals in the left and right directions of the respective vertical plates 5B and 5C. , bottom plate 5A, vertical plates 5B and 5C, and a plurality of projecting beams 5F for supporting left and right side frames 5D and 5E. Of the plurality of beams 5F, the front and rear beams 5F1 and 5F2 located on the right rear side are mounted with a post-processing device base 15, which will be described later.

The engine 9 is mounted on the revolving frame 5 so as to be positioned in front of the counterweight 6 and extend in the left and right directions of the upper revolving body 3 . As shown in FIGS. 2 to 4, a cooling fan 9A is provided on the left side of the engine 9 for supplying cooling air to a heat exchanger 11, which will be described later. On the right side of the engine 9, a hydraulic pump 12, which will be described later, is provided. Furthermore, a turbocharger 10, which will be described later, is provided in the upper front portion of the engine 9, and is connected to an exhaust manifold 9B. The engine 9 is supported in a vibration-isolating state on the revolving frame 5 via, for example, four anti-vibration mounts 9C (only two are shown in FIG. 4).

The supercharger 10 (turbocharger) is positioned, for example, on the front side of the engine 9 and connected to an exhaust manifold 9B, and has an exhaust port 10A that opens toward the right side of the upper rotating body 3 in the left-right direction. Here, the exhaust port 10A of the supercharger 10 discharges the exhaust gas from the engine 9, and is located above and below the lower end of the cylindrical body 26 of the first exhaust gas aftertreatment device 25, which will be described later. placed in position. The exhaust port 10A is connected to an exhaust pipe 35 that guides the exhaust gas to the exhaust gas post-treatment device 24 (first exhaust gas post-treatment device 25).

The heat exchanger 11 is arranged on the left side of the engine 9 . This heat exchanger 11 is provided so as to face the cooling fan 9A of the engine 9 . The heat exchanger 11 is composed of, for example, a radiator that cools engine cooling water, an oil cooler that cools hydraulic oil, an intercooler that cools air taken in by the engine 9, and the like.

A 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 hydraulic oil supplied from a hydraulic oil tank 13, which will be described later, toward a 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 provided on the right side of the revolving frame 5 . The hydraulic oil tank 13 stores hydraulic oil for driving the actuators provided in the undercarriage 2, the work 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 provided on the revolving frame 5 .

The post-processing device frame 15 is provided on the front and rear projecting beams 5F1 and 5F2 of the revolving frame 5 while straddling the hydraulic pump 12 in the front and rear directions. The post-treatment device mount 15 is for mounting an exhaust gas post-treatment device 24, which will be described later. The post-processing device base 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 revolving frame 5 . The front leg portion 16 is mounted on an overhanging beam 5F1 provided on the right rear side of the revolving frame 5 and on the front side in the forward and rearward directions. 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 projecting beam 5F1 and an upper front leg portion 16B rising from 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 revolving frame 5 . That is, the rear leg portion 17 faces the front leg portion 16 and the hydraulic pump 12 in the front and rear directions. The rear leg portion 17 is attached to an overhanging beam 5F2 provided on the right rear side of the revolving frame 5 on the rear side in the forward and rearward 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 projecting beam 5F2 and an upper rear leg portion 17B rising from 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 revolving frame 5. As shown in FIG. The auxiliary leg 18 has its lower end attached to the projecting beam 5F1 on the left side of the lower front leg 16A, and its upper end attached to the post-processing device mounting frame 19. As shown in FIG. The front leg portion 16, the rear leg portion 17, and the auxiliary leg portion 18 support an exhaust gas aftertreatment device 24 attached to an aftertreatment device mounting frame 19, which will be described later.

The post-processing device mounting frame 19 is positioned 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 post-treatment device mounting frame 19 is formed as a box-shaped body composed of a left side plate 19A, an upper plate 19B, a right side plate 19C and a lower plate 19D, and includes a first exhaust gas post-treatment device 25 and a second exhaust gas post-treatment device 25 which will be described later. A gas post-treatment device 30 is attached.

A left side plate 19A of the aftertreatment 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 aftertreatment device 25, which will be described later, is attached to the left side plate 19A using a plurality of bolts 20 (only two are shown in FIGS. 5 to 7). An inlet insertion hole 19A1 is provided on the front side (on the side of the upper front leg portion 16B) of the left side plate 19A so as to penetrate in the plate thickness direction (left and right directions). The inflow port insertion hole 19A1 is formed at a position corresponding to an inflow port 26A of the first exhaust gas aftertreatment device 25, which will be described later, and the inflow port 26A protrudes from the cylindrical body 26 of the first exhaust gas aftertreatment device 25. is inserted.

The upper plate 19B of the post-processing 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 aftertreatment device 30, which will be described later, is attached to the upper plate 19B via a mounting plate 21 using a plurality of (for example, two) bolts 22. As shown in FIG.

A right side plate 19C of the post-processing 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 is formed with an exhaust pipe insertion hole 19C1 at a position corresponding to the inlet 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 through the exhaust pipe insertion hole 19C1. A tool or the like can be inserted through the exhaust pipe insertion hole 19C1 when connecting the exhaust gas outflow side of the bent pipe 37 to the inflow port 26A of the first exhaust gas aftertreatment device 25. As shown in FIG.

A later-described cover member 39 is attached to the right side plate 19C at a position corresponding to the exhaust pipe insertion hole 19C1. A plurality of (for example, two) working openings 19C2 are formed in the right side plate 19C. The working opening 19C2 is for a tool or the like for tightening the 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, for example. is inserted.

The lower plate 19D of the post-processing 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 vertically. A firewall 23 extending downward is attached to the lower plate 19D (see FIG. 7). The firewall 23 serves as a partition member that separates an engine-side space in which the engine 9, the exhaust gas post-treatment device 24, etc. are arranged from a pump-side space in which the hydraulic pump 12 is arranged. The firewall 23 prevents the leaked hydraulic oil from scattering to the engine 9 side, for example, even if hydraulic oil leaks around the hydraulic pump 12 .

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

The exhaust gas post-treatment device 24 is connected to the exhaust gas outflow side (outlet side) of an exhaust pipe 35 (to be described later) connected to the exhaust port 10A of the engine 9 and attached to the post-treatment device frame 15 . The exhaust gas aftertreatment device 24 is composed of a first exhaust gas aftertreatment device 25 , a connecting pipe 28 and a second exhaust gas aftertreatment device 30 .

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

The cylindrical body 26 of the first exhaust gas post-treatment device 25 is formed as a closed container with both ends closed. As shown in FIGS. 4 and 8, at the upstream side of the tubular body 26, there is provided a front portion extending radially outward of the tubular body 26 from the opposite side of the engine 9 across the axis O1-O1 of the tubular body 26. A protruding tubular inlet 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 a bent pipe line 37 of an exhaust pipe 35, which will be described later. On the other hand, a bracket 26</b>B for mounting the first exhaust gas post-treatment device 25 to the post-treatment device mounting frame 19 is provided on the outer peripheral side of the cylindrical body 26 .

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 cellular cylindrical body, and has a large number of through holes in its axial direction. The inner surface is coated with a noble metal or the like. The oxidation catalyst 27 oxidizes and removes carbon monoxide (CO), hydrocarbons (HC), and the like contained in the exhaust gas by causing the exhaust gas to flow through each through-hole at 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 a second exhaust gas aftertreatment device 30 which will be described later. As shown in FIGS. 8 and 9, the connection pipe 28 is connected at its exhaust gas inflow side to the rear end (exhaust gas outflow side) of the tubular body 26 of the first exhaust gas aftertreatment device 25, and is curved in a U shape. and a curved portion 28A extending from the curved portion 28A to the upper side of the cylinder 26 in the front and rear directions in parallel with the cylinder 26. It is configured by the connected extension portion 28B.

As shown in FIG. 9 , the curved portion 28A of the connecting pipe 28 is positioned forward of the rear end of the tubular body 31 of the second exhaust aftertreatment device 30 (inflow port 26A side). That is, the curved portion 28A is curved so as not to protrude from the rear end of the cylindrical body 31 of the second exhaust aftertreatment device 30. As shown in FIG. In addition, as shown in FIG. 8, the extending portion 28B of the connecting pipe 28 is arranged so as to minimize the width and height of the exhaust aftertreatment device 24 in the lateral direction (left and right directions). It is arranged above 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 extension portion 28B of the connection pipe 28 and connected via a pump (both not shown) to a urea water tank for storing the urea water solution. The urea water injection nozzle 29 injects the urea water solution toward the exhaust gas flowing through the connecting pipe 28 .

The second exhaust gas post-treatment device 30 is arranged above the hydraulic pump 12 while being attached to the upper plate 19B of the post-treatment device mounting frame 19 . That is, the second exhaust gas aftertreatment device 30 is arranged diagonally above the first exhaust gas aftertreatment device 25 to the right. The second exhaust gas aftertreatment device 30 is connected to the exhaust gas outflow side of the connecting pipe 28, and extends in the front and rear directions in parallel with the tubular body 26 of the first exhaust gas aftertreatment device 25. a cylindrical cylindrical body 31, a selective reduction catalyst 32 that is arranged in the cylindrical body 31 and selectively reduces nitrogen oxides (NOx) with ammonia to decompose them into water and nitrogen, and the selective reduction catalyst 32. an oxidation catalyst 33 arranged downstream of the selective reduction catalyst 32 for oxidizing residual ammonia remaining after the reduction of nitrogen oxides by the selective reduction catalyst 32 and separating into nitrogen and water; and a tail pipe 34 protruding upward from.

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

As shown in FIG. 9, the axis O2-O2 of the tubular body 31 of the second exhaust gas aftertreatment device 30 is parallel to the axis O1-O1 of the tubular body 26 of the first exhaust gas aftertreatment device 25. there is Further, as shown in FIG. 8, the axis O2-O2 of the cylinder body 31 of the second exhaust gas aftertreatment device 30 is arranged in a state where the distance L1 to the axis line O1-O1 of the cylinder body 26 is made as small as possible. , is shifted to the right by an angle α with respect to the vertical line AA passing through the axis O1-O1 of the cylindrical body 26. FIG. This angle .alpha. is set so as not to protrude greatly toward the engine 9 side.

That is, the tubular body 31 of the second exhaust gas aftertreatment device 30 is arranged above and shifted to the right side frame 5E side (right side) with respect to the tubular body 26 of the first exhaust gas aftertreatment device 25. there is Further, the first exhaust gas aftertreatment device 25 and the second exhaust gas aftertreatment device 30 are arranged such that they partially overlap 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. It can be made compact. As a result, an empty space can be secured in the space on the side of the pump where the exhaust gas aftertreatment device 24 and the hydraulic pump 12 are arranged, so that this empty space can be effectively utilized.

As shown in FIG. 10, the selective reduction catalyst 32 is made of, for example, a ceramic cell-like cylindrical body, which has a large number of through-holes formed in its axial direction and whose inner surface is coated with a noble metal. The selective reduction catalyst 32 selectively reduces nitrogen oxides (NOx) contained in the exhaust gas discharged from the engine 9 with ammonia generated from an aqueous urea solution to decompose them into nitrogen and water. .

The oxidation catalyst 33 is made of a ceramic cell-like cylindrical body, substantially the same as the oxidation catalyst 27 described above. As a result, the oxidation catalyst 33 oxidizes residual ammonia remaining after nitrogen oxides are reduced by the selective reduction catalyst 32, and separates it into nitrogen and water.

The tail pipe 34 is positioned at a rear portion on the downstream side of the cylindrical body 31 (downstream side of the oxidation catalyst 33). 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 enters the cylindrical body 31, and the exhaust gas passes 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.

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

A horizontal conduit 36 of the exhaust pipe 35 extends along the length direction (left and right directions) of the engine 9 from the exhaust port 10A of the engine 9 below the cylinder 26 forming the first exhaust aftertreatment device 25. in a direction perpendicular to the axis O1--O1 of the cylindrical body 26 (left and right directions). In this case, the horizontal conduit 36 extends in the left-right direction of the revolving frame 5 under the inlet 26A formed in the cylindrical body 26 of the first exhaust aftertreatment device 25 .

The horizontal pipeline 36 includes an upper horizontal pipeline portion 36A that extends horizontally from the exhaust port 10A, and an upper horizontal pipeline portion 36A that slopes downward toward the lower side of the first exhaust gas aftertreatment device 25 from the tip side of the upper horizontal pipeline portion 36A. It is composed of an inclined pipe line portion 36B and a lower horizontal pipe line portion 36C located below the first exhaust gas aftertreatment device 25 and extending from the tip side of the inclined pipe line portion 36B toward the bent pipe line 37. there is That is, the horizontal pipeline 36 is formed in a crank shape by an upper horizontal pipeline portion 36A, an inclined pipeline portion 36B, and a lower horizontal pipeline portion 36C. In this case, as shown in FIG. 4, the lower horizontal pipeline portion 36C is positioned 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 base 15. ing.

The bent pipe line 37 of the exhaust pipe 35 bends upward from the tip end side of the lower horizontal pipe line portion 36C of the horizontal pipe line 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 curved pipe line 37 is bent in a U shape from the lower horizontal pipe line portion 36C toward the inflow port 26A of the cylindrical body 26 .

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

The bellows pipe 38 is provided in the lower horizontal pipeline portion 36C of the horizontal pipeline 36 . The bellows pipe 38 is formed, for example, as a bellows-shaped metal cylinder having a hole diameter larger than that of the lower horizontal pipe portion 36C, and reduces relative displacement (vibration) between the engine 9 and the first exhaust gas post-treatment device 25. Absorb. That is, since the exhaust gas post-treatment device 24 attached to the post-treatment device mount 15 provided on the revolving frame 5 and the engine 9 have different vibration systems, relative displacement between the two generated by the different vibration systems is absorbed by the bending deformation of the bellows tube 38.

Here, the inlet 26A of the tubular body 26 of the first exhaust gas aftertreatment device 25 is provided on the opposite side of the engine 9 with the axis O1-O1 of the tubular body 26 interposed therebetween. As a result, the exhaust pipe 35 can be formed with an elongated lower horizontal pipe line portion 36C. By providing the long bellows pipe 38 in the lower horizontal pipe line portion 36C, 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 accommodated within the lateral width L2 defined by the first exhaust gas aftertreatment device 25 and the second exhaust gas aftertreatment device 30. As shown in FIG. That is, the first exhaust gas post-treatment device 25, the second exhaust gas post-treatment device 30, and the bellows pipe 38 are arranged in order from the bottom in the upward and downward directions: the bellows pipe 38, the first exhaust gas post-treatment device 25. , the second exhaust gas aftertreatment device 30 are superimposed in this order.

Further, as shown in FIG. 9, the bellows pipe 38 is accommodated within a vertical dimension L3 defined by the first exhaust gas aftertreatment device 25 and the second exhaust gas aftertreatment device 30. As shown in FIG. As a result, the lateral (longitudinal direction of the engine 9) and longitudinal dimensions of the first exhaust gas aftertreatment device 25, the second exhaust gas aftertreatment device 30, and the bellows pipe 38 are suppressed. , they can be compactly arranged on the revolving 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 post-processing device mounting frame 19. As shown in FIG. The cover member 39 extends along the bent pipe line 37 and the lower horizontal pipe line portion 36C between the firewall 23 and the exhaust pipe insertion hole 19C1 formed in the right side plate 19C of the post-processing device mounting frame 19, thereby It serves as a partition member that partitions between the pump 12 and the curved pipe line 37 and between the hydraulic pump 12 and the lower horizontal pipe line portion 36C.

As shown in FIG. 7, the cover member 39 includes a mounting plate portion 39A mounted to the right side plate 19C of the aftertreatment device mounting frame 19, and protruding from the mounting plate portion 39A toward the right side (the side opposite to the engine 9). It includes a bent pipe line covering plate portion 39B extending along the bent pipe line 37, and a lower horizontal pipe line covering plate portion 39C extending from the bent pipe line covering plate portion 39B to the firewall 23 along the lower horizontal pipe line portion 36C. is formed by

The cover member 39 is attached to the post-processing device attachment frame 19 with bolts 40 with the attachment plate portion 39A 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 end of the lower horizontal pipeline covering plate portion 39C. The cover member 39 is attached to the firewall 23 with other bolts (not shown) while the firewall contact plate portion 39D is in contact with the firewall.

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

The hydraulic excavator 1 according to this embodiment has the configuration as described above, and the operation thereof will be described below.

First, the operator gets on the cab 7 and operates the engine 9 . The operator can operate the operating lever (not shown) for traveling arranged in the cab 7 to cause the hydraulic excavator 1 to travel, and operate the operating lever (not shown) for work. By doing so, the excavation work of earth and sand can be performed 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 aftertreatment device 25 through the exhaust pipe 35 from the exhaust port 10A. 10, the exhaust gas passes from the first exhaust gas aftertreatment device 25 through the connection pipe 28, through the second exhaust gas aftertreatment device 30, and through the tailpipe 34 into the atmosphere. discharged to

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

By the way, in the conventional technology 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 (lateral direction). A bellows pipe having a predetermined length is provided in the exhaust pipe in order to absorb relative displacement due to vibration between the engine and the exhaust aftertreatment device. Therefore, there is a possibility that a large space is required in the front, rear, left, and right directions of the vehicle body for arranging the exhaust gas aftertreatment device, the exhaust pipe, and the bellows pipe.

Therefore, in the present embodiment, the first exhaust gas post-treatment device 25, the second exhaust gas post-treatment device 30, and the exhaust pipe 35 are arranged so as to overlap vertically. Specifically, as shown in FIG. 8, the second exhaust gas post-treatment device 30 located on the upper side is located between the axis O1-O1 of the tubular body 26 of the first exhaust gas post-treatment device 25 and the second exhaust gas post-treatment device 25. With the distance L1 between the axis O2-O2 of the cylinder 31 of the gas post-treatment device 30 made as small as possible, the angle α It is arranged in a shifted position. By horizontally displacing 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. A connection pipe 28 is efficiently arranged between them.

As shown in FIGS. 8 and 9, a lower horizontal pipeline portion 36C that constitutes the horizontal pipeline 36 of the exhaust pipe 35 is arranged below the first exhaust gas aftertreatment device 25. As shown in FIG. That is, the exhaust pipe 35 is positioned within the vertical dimension L3 (length 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 housed compactly. As a result, the space for arranging the exhaust gas aftertreatment device 24 and the exhaust pipe 35 can be reduced.

A bellows pipe 38 that absorbs relative displacement between the engine 9 and the first exhaust gas post-treatment device 25 is provided in the lower horizontal pipe line portion 36C. As shown in FIG. 8, the bellows pipe 38 is compactly accommodated within the lateral width L2 formed by the first exhaust gas aftertreatment device 25 and the second exhaust gas aftertreatment device 30. As shown in FIG. 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.

A portion of the curved pipe line 37 of the exhaust pipe 35 protrudes from the right side plate 19C of the post-processing apparatus mounting frame 19 of the post-processing apparatus pedestal 15 as a projecting portion 37A. A protruding portion 37A of the curved pipeline 37 is covered with a curved pipeline covering plate portion 39B of a cover member 39 that shields between the curved pipeline 37 and the hydraulic pump 12 . As a result, for example, even if hydraulic fluid leaks around the hydraulic pump 12 , the leaked hydraulic fluid can be prevented from scattering in the bent 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 of the exhaust pipe 35 and the bellows pipe 38 . As a result, for example, even if hydraulic fluid leaks around the hydraulic pump 12, the leaked hydraulic fluid can be prevented from scattering to the lower horizontal pipeline portion 36C and the bellows pipe 38.

Further, the width of the post-treatment device mounting frame 19 is reduced by reducing the width L2 formed by the first exhaust gas post-treatment device 25 and the second exhaust gas post-treatment device 30 as much as possible. can be done. As a result, a portion (protruding portion 37A) of the bent pipe line 37 protrudes from the post-processing device mounting frame 19. By covering the protruding portion 37A with the cover member 39, the cover member 39 and the rear leg portion 17 are separated from each other. The space formed between can be effectively utilized. That is, the post-processing device mounting frame 19 has a large width when it is aligned with the protruding portion 37A of the bent pipeline 37. By covering only the portion 37A with the cover member 39, a space behind the cover member 39 can be secured.

Thus, the construction machine according to this embodiment includes a self-propelled vehicle body (lower traveling body 2 and upper rotating 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 cylindrical body 26 provided on the exhaust gas outflow side of the exhaust pipe 35, and the exhaust gas aftertreatment device 25 connected to the exhaust gas outflow side of the first exhaust gas aftertreatment device 25. and a second exhaust gas aftertreatment device 30 comprising a cylindrical body 31 provided on the exhaust gas outflow side of the connection pipe 28, and the exhaust gas from 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 respect to the axis O1-O1 of the cylindrical body 26 forming the first exhaust aftertreatment device 25, and is provided on the side opposite to the engine 9. The gas post-treatment device 30 is arranged above the first exhaust gas post-treatment device 25 so as to overlap the first exhaust gas post-treatment device 25 in the top and bottom directions.

A feature of this embodiment is that the exhaust pipe 35 extends along the length direction of the engine 9 from the exhaust port 10A of the engine 9 and forms the first exhaust aftertreatment device 25. A horizontal pipe 36 crosses the lower part of the body 26 in a direction perpendicular to the axis O1-O1 of the cylindrical body 26, and the first exhaust gas aftertreatment device is bent upward from the tip side of the horizontal pipe 36. 25 and a curved pipe line 37 connected to the exhaust gas inflow side (inflow port 26A).

Further, the horizontal pipe line 36 of the exhaust pipe 35 includes an upper horizontal pipe line portion 36A extending horizontally from the exhaust port 10A and the first exhaust gas post-treatment from the tip side of the upper horizontal pipe line portion 36A. A slanted pipeline portion 36B that slopes downward toward the lower side of the device 25, and an inclined pipeline portion 36B that is located below the first exhaust gas post-treatment device 25 and extends from the tip side of the slanted pipeline portion 36B to the bent pipeline 37. and a lower horizontal pipe line portion 36C extending toward.

A bellows pipe 38 that absorbs relative displacement between the engine 9 and the first exhaust gas post-treatment device 25 is provided in the lower horizontal pipeline portion 36C of the horizontal pipeline 36 . Also, the bellows pipe 38 is accommodated within the lateral width L2 defined by the first exhaust gas aftertreatment device 25 and the second exhaust gas aftertreatment device 30 .

Further, one side of the engine 9 in the length direction where the first exhaust gas aftertreatment device 25 and the second exhaust gas aftertreatment device 30 are provided is provided with an engine 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 are connected to the vehicle body while straddling the hydraulic pump 12 in the front and rear directions of the vehicle body. The curved pipe line 37 protrudes from the post-processing device frame 15 toward the side opposite to the engine 9, and the protruding portion 37A is covered by a cover member 39. covered.

In the above-described embodiment, the exhaust port 10A of the engine 9 is positioned above the lower end of the first exhaust gas post-treatment device 25, and the horizontal pipe 36 of the exhaust pipe 35 is divided into the upper horizontal pipe portion 36A and the horizontal pipe portion 36A. The case where it is configured by 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. For example, when the exhaust port 10A of the engine 9 is positioned below the lower end of the first exhaust gas post-treatment device 25, the horizontal pipe 36 is positioned at the exhaust port of the engine. It may be formed in a straight line from to the bent pipe line 37 .

Further, in the above-described embodiment, the case where the inclined pipeline portion 36B is formed between the upper horizontal pipeline portion 36A and the lower horizontal pipeline portion 36C of the horizontal pipeline 36 has been described as an example. However, the present invention is not limited to this. 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 (upward and downward directions).

Further, in the above-described embodiment, the case where only the oxidation catalyst 27 is provided in the cylindrical body 26 of the first exhaust gas post-treatment 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 downstream of the oxidation catalyst 27 inside the cylindrical body 26 of the first exhaust gas aftertreatment device 25 . This particulate matter removal filter collects particulate matter (PM) in the exhaust gas discharged from the engine, burns it and removes it, thereby purifying the exhaust gas.

Further, in the above-described embodiment, the hydraulic excavator 1 including the crawler-type undercarriage 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 equipped with a wheel-type undercarriage. In addition, it can be widely applied to other construction machines such as wheel loaders, dump trucks, and hydraulic cranes.

1 Hydraulic excavator (construction machinery)
2 Undercarriage (body)
3 Upper revolving body (body)
9 Engine 10 Turbocharger 10A Exhaust Port 12 Hydraulic Pump 15 Aftertreatment Device Base 25 First Exhaust Gas Aftertreatment Device 26 Cylinder 26A Inlet 28 Connection Pipe 30 Second Exhaust Gas Aftertreatment Device 31 Cylinder 35 Exhaust Pipe 36 horizontal pipe line 36A upper horizontal pipe line portion 36B inclined pipe line portion 36C lower horizontal pipe line portion 37 bent pipe line 38 bellows pipe 39 cover member O1-O1 axis of cylindrical body 26 L2 width

Claims (4)

A self-propellable 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 connecting pipe connected to the exhaust gas outflow side of the first exhaust gas aftertreatment device; and a connecting pipe provided on the exhaust gas outflow side of the connecting pipe. and a second exhaust gas aftertreatment device comprising a cylindrical body,
The first exhaust gas aftertreatment device and the second exhaust gas aftertreatment device are attached to the aftertreatment device mount,
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 respect to the axis of the tubular body forming the first exhaust gas aftertreatment device. provided on the side,
The construction machine, wherein 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 vertical direction,
The exhaust pipe includes a horizontal pipe extending from the exhaust port of the engine and below the cylindrical body forming the first exhaust aftertreatment device, and a horizontal pipe bending upward from a tip side of the horizontal pipe. and a curved pipeline connected to the inlet of the first exhaust aftertreatment device,
a midway portion of the curved pipeline protrudes from the post-processing device base toward the side opposite to the engine;
a bellows pipe that absorbs relative displacement between the engine and the first exhaust gas aftertreatment device is provided in the horizontal pipe,
The bellows pipe, the first exhaust gas aftertreatment device, and the second exhaust gas aftertreatment device are arranged in this order from the bottom in the upward and downward directions: the bellows pipe, the first exhaust gas aftertreatment device, the A second exhaust gas aftertreatment device is arranged in an overlapping order, 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 housed and arranged. The horizontal pipe line of the exhaust pipe includes an upper horizontal pipe line portion extending horizontally from the exhaust port, and a tip side of the upper horizontal pipe line portion directed downward toward the lower side of the first exhaust gas post-treatment device. and a lower horizontal pipeline portion located below the first exhaust gas post-treatment device and extending from the tip side of the inclined pipeline portion toward the curved pipeline. 2. The construction machine according to claim 1, characterized in that: 3. The construction machine according to claim 2, wherein the bellows pipe is provided in the lower horizontal pipeline portion of the horizontal pipeline. 2. The construction machine according to claim 1, wherein a protruding portion of said curved pipe line protruding from said post-processing device mount toward a side opposite to said engine is covered with a cover member.

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