阅读说明：本技术 建筑机械 (Construction machine ) 是由 石川喜久 于 2020-01-31 设计创作，主要内容包括：回转作业车(1)具备：发动机(32)、废气处理装置(71)以及发动机盖(33)。废气处理装置(71)对发动机(32)的废气进行处理。发动机盖(33)对发动机(32)及废气处理装置(71)进行覆盖。废气处理装置(71)具备DPF装置(81)和SCR装置(82)。废气在通过DPF装置(81)进行处理之后,通过SCR装置(82)进行处理。DPF装置(81)及SCR装置(82)分别配置成：长度方向沿着上下方向。DPF装置(81)及SCR装置(82)在与上下方向垂直的方向上并排配置。(A rotary work vehicle (1) is provided with: an engine (32), an exhaust gas treatment device (71), and an engine cover (33). An exhaust gas treatment device (71) treats exhaust gas of an engine (32). The engine cover (33) covers the engine (32) and the exhaust gas treatment device (71). The exhaust gas treatment device (71) is provided with a DPF device (81) and an SCR device (82). The exhaust gas is treated by a DPF device (81) and then treated by an SCR device (82). The DPF device (81) and the SCR device (82) are respectively configured in a way that: the longitudinal direction is along the up-down direction. The DPF device (81) and the SCR device (82) are arranged side by side in a direction perpendicular to the vertical direction.)

1. A construction machine is characterized by comprising:

an engine;

an exhaust gas treatment device that treats exhaust gas of the engine; and

an engine cover that covers the engine and the exhaust gas treatment device,

the exhaust gas treatment device is provided with a first treatment device and a second treatment device,

the exhaust gas is treated by the second treatment device after being treated by the first treatment device,

the first processing device and the second processing device are respectively configured to: the length direction is along the up-down direction,

the first processing device and the second processing device are arranged side by side in a direction perpendicular to a vertical direction.

2. The construction machine according to claim 1,

a first treatment device inlet is formed at the lower part of the first treatment device,

a first treating device discharge port is formed at the upper part of the first treating device,

a second treatment device inlet is formed at the lower part of the second treatment device,

a second treating device discharge port is formed at the upper part of the second treating device,

the first treatment device outlet is connected to the second treatment device inlet.

3. The construction machine according to claim 1 or 2,

the construction machine is provided with a hydraulic pump,

an input shaft of the hydraulic pump is disposed coaxially with a drive shaft of the engine to rotate integrally,

the exhaust gas treatment device is disposed above the hydraulic pump in the engine head.

Technical Field

The present invention relates to a construction machine.

Background

Conventionally, a construction machine provided with an exhaust gas treatment device for an engine is known. Patent documents 1 and 2 disclose such a construction machine.

Patent document 1 discloses a rear small swing type construction machine. In the construction machine of patent document 1, the exhaust gas treatment device is provided with: an engine room is formed by a part of a connecting wall of a rear side peripheral wall which is a roughly semicircular arc-shaped peripheral wall protruding to the rear side. The exhaust gas treatment device has a first treatment unit and a second treatment unit. The first processing unit and the second processing unit are respectively configured to: the rear side peripheral wall is located at a position closest to the inner surface wall of the connecting wall of the rear side peripheral wall on a positioning line along the inner surface wall of the connecting wall of the rear side peripheral wall with a certain interval.

Patent document 2 discloses a small swing excavator. The small swing excavator includes an upper swing body having a rear portion in the shape of an arc. An exhaust gas treatment device is provided in the upper slewing body. The exhaust gas treatment device is disposed on the right side of the engine disposed in the center of the rear portion of the upper slewing body. The exhaust gas treatment device is disposed so as to be inclined with respect to the front-rear direction of the upper slewing body.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2011-157721

Patent document 2: japanese patent laid-open publication No. 2016-176318

Disclosure of Invention

The patent document 1 has a configuration in which: the first treatment unit and the second treatment unit of the exhaust gas treatment device are disposed in a state in which their longitudinal directions lie down in the front-rear direction. Therefore, a relatively wide dead space is formed between each of the outer wall extending in the longitudinal direction in the first treatment section and the outer wall extending in the longitudinal direction in the second treatment section and the connecting wall of the rear side peripheral wall. Accordingly, the exhaust gas treatment device can be easily disposed to press the space around the engine. Therefore, it is difficult to say that the engine maintainability is good.

Further, patent document 2 has a configuration in which: the exhaust gas treatment device is disposed so as to be inclined with respect to the front-rear direction of the upper slewing body. Here, the exhaust gas treatment device is disposed in a state in which the longitudinal direction lies along a direction orthogonal to the vertical direction. Accordingly, the exhaust gas treatment device is likely to crush the space around the engine, and as in patent document 1, there is room for improvement from the viewpoint of engine maintainability.

The present invention has been made in view of the above circumstances, and an object thereof is to improve the maintainability of an engine in a construction machine provided with an exhaust gas treatment device for the engine.

The problems to be solved by the present invention are as described above, and means for solving the problems and effects thereof will be described below.

According to an aspect of the present invention, there is provided a construction machine configured as follows. That is, the construction machine includes: an engine, an exhaust gas treatment device, and an engine cover. The exhaust gas treatment device treats exhaust gas of the engine. The engine cover covers the engine and the exhaust gas treatment device. The exhaust gas treatment device is provided with a first treatment device and a second treatment device. The exhaust gas is treated by the second treatment device after being treated by the first treatment device. The first processing device and the second processing device are respectively configured to: the longitudinal direction is along the up-down direction. The first processing device and the second processing device are arranged side by side in a direction perpendicular to a vertical direction.

Thus, the first treatment device and the second treatment device of the exhaust gas treatment device can be disposed in a compact space in the engine head. Therefore, the space around the engine can be prevented from being pressed by the exhaust gas treatment device. In addition, since the engine and the exhaust gas treatment device can be disposed by effectively utilizing the space, a blind spot in the engine cover can be made less likely to occur.

In the above construction machine, the following configuration is preferably adopted. That is, a first treatment device inlet is formed at a lower portion of the first treatment device. A first treatment device discharge port is formed in an upper portion of the first treatment device. A second treatment device inlet is formed at a lower portion of the second treatment device. A second treatment device discharge port is formed in an upper portion of the second treatment device. The first treatment device outlet is connected to the second treatment device inlet.

In this way, in the exhaust gas treatment device, the exhaust gas discharged from the exhaust port of the engine can be made to flow from the lower side to the upper side in each of the first treatment device and the second treatment device. Therefore, it is possible to secure a path length necessary for the exhaust gas treatment in each device and realize a simple layout on the premise that the exhaust gas treated in the exhaust gas treatment device is discharged from the upper portion.

In the above construction machine, the following configuration is preferably adopted. That is, the construction machine is provided with a hydraulic pump. The hydraulic pump is coupled to a drive shaft of the engine. The exhaust gas treatment device is disposed above the hydraulic pump in the engine head.

Thereby, it is possible to realize: the layout of the space in the engine head including the hydraulic pump is more effectively utilized.

Drawings

Fig. 1 is a perspective view showing an entire configuration of a swing working vehicle according to an embodiment of the present invention.

Fig. 2 is a plan view showing the internal structure of the engine cover.

Fig. 3 is a perspective view showing the internal structure of the engine cover.

Fig. 4 is a perspective view showing the configuration of the exhaust gas treatment device.

Detailed Description

Next, embodiments of the present invention will be described with reference to the drawings. Fig. 1 is a perspective view showing an entire configuration of a swing working vehicle 1 according to an embodiment of the present invention.

A swing working vehicle (construction machine) 1 shown in fig. 1 is a rear small swing type backhoe, and includes: a traveling section 11 and a turning section 12.

The traveling unit 11 includes 1 pair of left and right front wheels 21 and rear wheels 22. The traveling unit 11 can drive the left and right front wheels 21 and rear wheels 22 to perform various traveling such as forward or backward traveling, turning, and the like.

The turning unit 12 includes: revolving frame 31, engine 32, engine cover 33, steering section 34, and working device 35.

Revolving frame 31 is disposed above traveling unit 11, and is supported by traveling unit 11 so as to be rotatable about a vertical axis. The revolving frame 31 can be rotated with respect to the traveling unit 11 by driving the revolving motor.

The engine 32 is configured as a diesel engine, for example. The engine 32 is disposed at the rear of the revolving portion 12. Engine 32 is supported by revolving frame 31.

The engine cover 33 covers the components such as the engine 32. An engine cover 33 is provided above revolving frame 31. The engine cover 33 is arranged on the revolving frame 31 in parallel with the cab 38 of the steering unit 34.

The operation unit 34 includes: a driver's seat on which an operator sits, various operating components, and a cab 38 that covers them. The operator can provide various instructions to the swing working vehicle 1 by operating the above-described operation members. The operation unit 34 is disposed at the front left portion of the rotation unit 12.

Hereinafter, in the case of explaining the positional relationship and the like of the respective members attached to the turning portion 12, the front-rear direction and the left-right direction are defined with the direction in which the operator sitting on the driver's seat faces as front.

The working device 35 includes: boom 41, arm 42, bucket 43, boom cylinder 44, arm cylinder 45, and bucket cylinder 46.

Boom 41 is an elongated member, and a base end portion thereof is rotatably supported by a front portion of revolving frame 31. An arm cylinder 44 is attached to the boom 41, and the boom cylinder 44 can extend and contract to rotate the boom 41.

The arm 42 is an elongated member, and a base end portion thereof is rotatably supported by a tip end portion of the boom 41. An arm cylinder 45 is attached to the arm 42, and the arm 42 can be rotated by extending and contracting the arm cylinder 45.

The bucket 43 is configured as a container-shaped member, and an end portion thereof is rotatably supported by a distal end portion of the arm 42. A bucket cylinder 46 is attached to the bucket 43, and the bucket 43 can be rotated by extending and contracting the bucket cylinder 46 to perform a cutting operation and an unloading operation.

Next, the structure inside the engine cover 33 will be explained. Fig. 2 is a plan view showing the internal structure of the engine cover 33. Fig. 3 is a perspective view showing the internal structure of the engine cover 33.

As shown in fig. 2 and 3, a bent portion 39 protruding rearward in a plan view is provided at the rear portion of revolving frame 31. The engine cover 33 is provided on the revolving frame 31 in a state where the rear portion thereof is bent along the bent portion 39 of the revolving frame 31.

Disposed inside the engine cover 33 are: the engine 32, the exhaust gas treatment device 71, the hydraulic pump 72, the oil cooler 73, the fuel tank 74, the hydraulic oil tank 75, and the like.

The engine 32 is disposed at the rear center in the engine cover 33. The engine 32 is opposed to a bent portion of the peripheral wall of the engine cover 33 located at the rear of the engine 32. The engine 32 includes a drive shaft, not shown, horizontally arranged in the left-right direction.

The exhaust gas treatment device 71 treats exhaust gas discharged from the engine 32. Exhaust gas treatment device 71 is disposed on the right side of engine 32 on revolving frame 31. The exhaust gas treatment device 71 is disposed substantially in the left-right direction in parallel with the engine 32. The exhaust gas treatment device 71 is disposed above the hydraulic pump 72.

The hydraulic pump 72 supplies hydraulic oil to a hydraulic device such as a cylinder of the working device 35. The hydraulic pump 72 is attached to the right side surface of the engine body of the engine 32. The input shaft of the hydraulic pump 72 is connected in series with the drive shaft of the engine 32. Accordingly, the hydraulic pump 72 sucks and discharges the hydraulic oil in conjunction with the driving of the engine 32.

Hydraulic pump 72 is disposed on the right side of engine 32 on revolving frame 31. The hydraulic pump 72 is adjacent the engine 32. The hydraulic pump 72 is provided in a space between the revolving frame 31 and the exhaust gas treatment device 71 (below the exhaust gas treatment device 71) in the vertical direction. In other words, the exhaust gas treatment device 71 is disposed above the hydraulic pump 72.

The oil cooler 73 is disposed on the left side of the engine 32. An air cleaner 77 is disposed on the left side of the oil cooler.

The fuel tank 74 and the hydraulic oil tank 75 are disposed at the front right of the engine 32 and at the front of the exhaust gas treatment device 71. The fuel tank 74 and the hydraulic oil tank 75 are arranged side by side in the left-right direction.

Next, the exhaust gas treatment device 71 will be explained. Fig. 4 is a perspective view showing the configuration of the exhaust gas treatment device 71.

As shown in fig. 4, the exhaust gas treatment device 71 includes: a DPF device 81 as a first treatment device, and an SCR device 82 as a second treatment device. DPF is a short for Diesel Particulate Filter (Diesel Particulate Filter). SCR is an abbreviation for Selective Catalytic Reduction (Selective Catalytic Reduction).

As shown in fig. 2 and 3, the DPF device 81 and the SCR device 82 are arranged side by side so that their longitudinal directions are in the vertical direction (in a state of being raised up, respectively). Both DPF device 81 and SCR device 82 are disposed above revolving frame 31, and are supported by revolving frame 31 via support member 85.

The DPF device 81 is provided near the bent portion 39 of the revolving frame 31, and faces the bent portion of the rear portion of the peripheral wall of the engine cover 33. The DPF device 81 is disposed closer to the engine 32 than the SCR device 82.

The DPF device 81 can remove Particulate Matter (PM) contained in the exhaust gas. The DPF device 81 includes: an oxidation catalyst, a filter, and a DPF casing 87 housing them.

The oxidation catalyst is: a catalyst composed of platinum or the like for oxidizing (combusting) unburned fuel, carbon monoxide, nitrogen monoxide, and the like contained in the exhaust gas. The filter is configured as, for example, a wall-flow type filter, and traps particulate matter contained in the exhaust gas treated by the oxidation catalyst.

The DPF casing 87 is a substantially cylindrical hollow member. The DPF casing 87 is formed to be elongated in the axial direction of the cylinder. The DPF casing 87 is disposed at a position adjacent to the engine 32 so that the longitudinal direction thereof extends in the vertical direction.

The shape of the DPF casing 87 corresponds to the outer shape of the DPF device 81. Therefore, the longitudinal direction of the DPF casing 87 corresponds to the longitudinal direction of the DPF device 81. The DPF device 81 is disposed such that the longitudinal direction thereof is along the vertical direction in the same manner as the longitudinal direction of the DPF casing 87.

The DPF device 81 is provided with a first inlet (first treatment device inlet) 91 and a first outlet (first treatment device outlet) 92. The first introduction port 91 is disposed below the DPF device 81. The first exhaust port 92 is disposed above the DPF device 81. The first introduction port 91 and the first discharge port 92 are connected to each other via an internal space of the DPF casing 87. The exhaust gas enters the DPF casing 87 through the first introduction port 91 and is discharged through the first discharge port 92.

The first introduction port 91 is disposed below (one end side in the longitudinal direction) the DPF casing 87 along the vertical direction: the DPF casing 87 has an opening at its outer peripheral surface. The first exhaust port 92 is disposed on the upper side (the other end side in the longitudinal direction) of the DPF casing 87 such that: the DPF casing 87 has an opening in its upper surface.

The first introduction port 91 is connected to an exhaust port of the engine 32 by an appropriate pipe or the like. The first outlet 92 is connected to a second inlet 93 of the SCR device 82 by a connecting pipe 96 described later.

The SCR device 82 is provided near the bent portion 39 of the revolving frame 31, and faces the bent portion of the rear portion of the peripheral wall of the engine cover 33. The SCR device 82 is disposed at a position farther from the engine 32 than the DPF device 81.

The SCR device 82 can remove NOx contained in the exhaust gas. The SCR device 82 includes: an SCR catalyst, an ammonia oxidation catalyst, and an SCR case 88 housing these catalysts.

The SCR catalyst is made of a material such as zeolite or ceramic that adsorbs ammonia. The ammonia oxidation catalyst is: a catalyst for preventing ammonia desorbed from the SCR catalyst or not adsorbed to the SCR catalyst from being released to the outside. The ammonia oxidation catalyst is an oxidation catalyst such as platinum for oxidizing ammonia, and converts the ammonia into nitrogen, oxygen monoxide, water, and the like.

The SCR case 88 is a hollow member having a substantially cylindrical shape. The SCR housing 88 is formed to be elongated in the axial direction of the cylinder. The SCR case 88 is disposed at a position adjacent to the DPF case 87 such that the longitudinal direction thereof extends in the vertical direction.

The shape of the SCR housing 88 corresponds to the external shape of the SCR device 82. Therefore, the longitudinal direction of the SCR housing 88 corresponds to the longitudinal direction of the SCR device 82. The SCR device 82 is disposed so that the longitudinal direction thereof is along the vertical direction in the same manner as the longitudinal direction of the SCR case 88.

Both the DPF device 81 and the SCR device 82 are disposed in a posture standing up so as to extend in the vertical direction. Therefore, the longitudinal directions of the DPF device 81 and the SCR device 82 are parallel to each other. The DPF device 81 and the SCR device 82 are arranged side by side with an appropriate (small) interval in a direction orthogonal to the direction in which they extend (longitudinal direction). Specifically, the SCR device 82 is positioned right in front (diagonally forward) of the DPF device 81. The DPF device 81 and the SCR device 82 have portions overlapping each other when viewed in a direction in which the DPF device 81 and the SCR device 82 are arranged. This makes it possible to reduce the size of the exhaust gas treatment device 71 in the vertical direction.

The SCR device 82 is provided with a second inlet (second treatment device inlet) 93 and a second outlet (second treatment device outlet) 94. The second introduction port 93 is disposed below the SCR device 82. The second exhaust port 94 is disposed above the SCR device 82. The second inlet 93 and the second outlet 94 are connected to each other via an internal space of the SCR case 88. The exhaust gas enters the interior of the SCR housing 88 from the second introduction port 93 and is discharged from the second discharge port 94.

The second introduction port 93 is connected to the first discharge port 92 of the DPF device 81 through a connection pipe 96. A discharge pipe 95 shown in fig. 1 is connected to the second discharge port 94. The exhaust pipe 95 allows the exhaust gas treated by the exhaust gas treatment device 71 to escape to the outside space of the engine cover 33. The opening of the exhaust pipe 95 formed on the outer side of the engine cover 33 faces away from the operation portion 34.

The second introduction port 93 is disposed below (one end portion side in the longitudinal direction) the SCR case 88 along the vertical direction: the SCR case 88 is open on the side. The second discharge port 94 is disposed on the upper side (the other end side in the longitudinal direction) of the SCR housing 88 such that: the SCR case 88 is open on the side.

The connection pipe 96 has: a straight portion 97, a first connection end portion 98, and a second connection end portion 99.

A straight portion 97 is formed at an intermediate portion of the exhaust gas path in the connection pipe 96. The straight portion 97 is formed such that: linearly extends in a direction (vertical direction) parallel to the DPF casing 87 and the SCR casing 88.

The first connection end 98 is connected to the linear portion 97 at one end in the longitudinal direction of the linear portion 97 perpendicularly. The first connection end 98 is appropriately bent to connect with the first discharge port 92 formed in the upper surface of the DPF device 81.

The end of the second connection end 99 opposite to the first connection end 98 in the longitudinal direction of the straight portion 97 is perpendicularly connected to the straight portion 97. The second connection end 99 is connected to the second introduction port 93 of the SCR device 82.

A urea solution injection unit 100 is provided in the connection pipe 96. Urea solution injection unit 100 is disposed in the vicinity of the portion where first connection end 98 and straight line portion 97 are connected. Urea solution injection unit 100 can inject urea solution into the exhaust gas flowing through connection pipe 96.

The urea water is injected from above into the exhaust gas flowing from above to below in the straight portion 97 of the connection pipe 96. By injecting urea water in a path of exhaust gas flowing linearly and in an upward direction along the path, urea can be hydrolyzed well, and ammonia necessary for the reduction treatment of NOx can be efficiently generated.

The urea solution injection unit 100 includes: a urea solution injection nozzle 101 for injecting urea solution, a urea solution injection pipe 102, and a urea solution pump. Urea solution injection nozzle 101 is provided above connection pipe 96.

The urea water pump sucks urea water from a urea water tank, not shown, and sends the urea water to the urea water injection nozzle 101 through a urea water injection pipe 102. The urea water tank may be provided at any position of the turning part 12, but for example, a space disposed below the exhaust gas treatment device 71 may be considered.

With this configuration, the exhaust gas discharged from the engine 32 is sent to the exhaust gas treatment device 71, and then discharged to the outside of the engine cover 33. In the exhaust gas treatment device 71, the exhaust gas is first treated by the DPF device 81 and then treated by the SCR device 82.

Specifically, the exhaust gas is discharged from the exhaust port of the engine 32, and then introduced into the DPF casing 87 of the DPF device 81 through the first introduction port 91. After being introduced into the DPF casing 87, the exhaust gas is treated by the oxidation catalyst and the filter, flows upward from the lower side of the DPF casing 87, and is discharged from the first discharge port 92 to the connection pipe 96.

Then, the exhaust gas flows from the first outlet 92 of the DPF device 81 to the second inlet 93 of the SCR device 82 from the upper side to the lower side through the connection pipe 96. At this time, in connection pipe 96, urea solution is injected into the exhaust gas by urea solution injection unit 100. Thereby, urea is hydrolyzed to generate ammonia. The exhaust gas containing ammonia is introduced from the inside of the connection pipe 96 into the SCR case 88 of the SCR device 82 through the second introduction port 93.

After being introduced into the SCR housing 88, the exhaust gas containing ammonia is treated by the SCR catalyst and the ammonia oxidation catalyst, flows upward from the lower side of the SCR housing 88, and is discharged to the outside from the second discharge port 94.

Within the SCR housing 88, ammonia in the exhaust gas is adsorbed to the SCR catalyst. NOx contained in the exhaust gas is reduced by contacting the SCR catalyst adsorbed with ammonia, and is converted into nitrogen gas and water. Ammonia desorbed from the SCR catalyst or not adsorbed to the SCR catalyst is oxidized by the ammonia oxidation catalyst to become nitrogen, oxygen monoxide, water, and the like.

In the present embodiment, the exhaust gas treatment device 71 is disposed on the side (right side) of the engine 32 such that the DPF device 81 and the SCR device 82 are horizontally aligned along the vertical direction. Therefore, since the exhaust gas treatment device 71 can be disposed slightly apart from the engine 32, a wide space for maintenance can be secured around the engine 32 (particularly, above). In particular, in the present embodiment, when the engine 32 is to be serviced, the engine 32 is approached from above, and therefore, the arrangement of the exhaust gas treatment device 71 as described above is particularly advantageous.

Both the DPF device 81 and the SCR device 82 constituting the exhaust gas treatment device 71 are disposed near the rear curved portion of the peripheral wall of the engine cover 33. Therefore, the exhaust gas treatment device 71 can be compactly disposed at the end of the internal space of the engine cover 33, so that dead space is less likely to occur, and the space can be effectively utilized. As a result, for example, it is easy to ensure a large capacity of the operating oil tank 75 and the fuel tank 74.

In particular, in the present embodiment, the exhaust gas treatment device 71 is supported above the hydraulic pump 72. Therefore, a layout that more effectively utilizes the space inside the engine cover 33 can be realized. For example, in addition to the hydraulic pump 72, components (such as a component for supplying urea water) related to the exhaust gas treatment device 71 may be disposed in a space below the exhaust gas treatment device 71.

The exhaust gas is supplied to the lower portion of the DPF device 81, flows upward, and is discharged from the upper portion of the DPF device 81. Then, the exhaust gas flows downward in the connection pipe 96 and is supplied to the lower portion of the SCR device 82. The exhaust gas then flows upward in the SCR device 82, and is discharged from the upper portion of the SCR device 82. In this way, the exhaust gas flows from the bottom to the top in each of the DPF device 81 and the SCR device 82 while passing through the path that makes 2U-turns in the vertical direction. Therefore, the path length required for effective treatment of the exhaust gas in each device can be sufficiently ensured, and the entire exhaust gas treatment device 71 can be configured compactly. Further, since the urea water is added to the exhaust gas flowing from the top to the bottom in the connection pipe 96, the path length for generating ammonia can be sufficiently secured. Finally, since the exhaust gas is discharged from the upper portion of the exhaust gas treatment device 71, the exhaust gas treatment device can be easily adapted to the layout in which the opening of the discharge pipe 95 is arranged above the engine cover 33 like the revolving work vehicle 1 of the present embodiment.

As described above, the revolving work vehicle 1 of the present embodiment includes: an engine 32, an exhaust gas treatment device 71, and an engine cover 33. The exhaust gas treatment device 71 treats exhaust gas of the engine 32. The engine cover 33 covers the engine 32 and the exhaust gas treatment device 71. The exhaust gas treatment device 71 includes a DPF device 81 and an SCR device 82. The exhaust gas is treated by the DPF device 81 and then treated by the SCR device 82. The DPF device 81 and the SCR device 82 are respectively arranged such that: the longitudinal direction is along the up-down direction. The DPF device 81 and the SCR device 82 are arranged side by side in a direction perpendicular to the vertical direction.

Thus, the DPF device 81 and the SCR device 82 of the exhaust gas treatment device 71 can be disposed in a compact space in the engine cover 33. Therefore, the space around the engine 32 can be prevented from being pressed by the exhaust gas treatment device 71. Since the engine 32 and the exhaust gas treatment device 71 can be disposed by effectively utilizing the space, the blind space in the engine cover 33 can be made less likely to occur.

In the revolving work vehicle 1 of the present embodiment, the first introduction port 91 is formed in the lower portion of the DPF device 81. A first exhaust port 92 is formed in an upper portion of the DPF device 81. A second introduction port 93 is formed in a lower portion of the SCR device 82. A second exhaust port 94 is formed in an upper portion of the SCR device 82. The first discharge port 92 is connected to the second introduction port 93.

Thus, in the exhaust gas treatment device 71, the exhaust gas discharged from the exhaust port of the engine 32 can flow from the lower side to the upper side in each of the DPF device 81 and the SCR device 82. Therefore, it is possible to secure a path length necessary for the exhaust gas treatment in each device and realize a simple layout on the premise that the exhaust gas treated in the exhaust gas treatment device 71 is discharged from the upper portion.

The swing working vehicle 1 of the present embodiment is provided with a hydraulic pump 72. The input shaft of the hydraulic pump 72 is disposed coaxially with the drive shaft of the engine 32 and rotates integrally therewith. The exhaust gas treatment device 71 is disposed above the hydraulic pump 72 in the engine head 33.

Thus, when the drive shaft of the engine 32 is disposed horizontally, the exhaust gas treatment device 71 is disposed above the hydraulic pump 72 attached to the end of the drive shaft, and therefore the space above the engine 32 is not covered with the exhaust gas treatment device 71. Therefore, maintenance of the engine 32 is easily performed from the upper side.

Although the preferred embodiments of the present invention have been described above, the above configuration may be modified as follows.

The direction in which the DPF devices 81 and the SCR devices 82 are arranged is not limited to the oblique direction, and may be, for example, the front-rear direction or the left-right direction.

The first introduction port 91 may be disposed on the lower surface of the DPF device 81. The first exhaust port 92 may be disposed on the outer peripheral surface of the upper portion of the DPF device 81.

The second introduction port 93 may be disposed on the lower surface of the SCR device 82. The second exhaust port 94 may be disposed on an upper surface of the SCR device 82.

The shape of the connection pipe 96 connecting the DPF device 81 and the SCR device 82 is not limited to the shape shown in fig. 4 and the like, and may be appropriately changed.

Many modifications and variations of the present invention are possible in light of the above teachings. Thus, it can be understood that: the present invention can be practiced in the claims by a method other than the method described in the present specification.

Description of reference numerals 1 Rotary working vehicle (construction machine)

32 engine

33 Engine cover

71 exhaust gas treatment device

72 hydraulic pump

81DPF device (first treatment device)

82SCR device (second treatment device)

91 a first inlet (first treating device inlet) 92 a first outlet (first treating device outlet) 93 a second inlet (second treating device inlet) 94 a second outlet (second treating device outlet).