JP5914410B2 - Construction machinery - Google Patents

Description

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

  In general, a hydraulic excavator as a construction machine is provided with a self-propelled lower traveling body, an upper revolving body that is turnably mounted on the lower traveling body, and a front-rear side of the upper revolving body that can be raised and lowered. And a work device. The upper swing body is mounted with a cab, a fuel tank, a hydraulic oil tank and the like on the front side of the swing frame, and an engine, a hydraulic pump and the like on the rear side of the swing frame.

  A diesel engine is generally used as an engine of a hydraulic excavator. This diesel engine is supposed to discharge harmful substances such as particulate matter (PM) and nitrogen oxides (NOx). Therefore, the hydraulic excavator is configured such that an exhaust gas aftertreatment device is provided in an exhaust pipe that forms an exhaust gas passage of the engine. This exhaust gas aftertreatment device includes a PM collection device (usually also called Diesel Particulate Filter, abbreviated as DPF) for collecting particulate matter contained in the exhaust gas, and nitrogen oxide contained in the exhaust gas. A NOx purification device that purifies (NOx) is known. Furthermore, as an exhaust gas aftertreatment device, a silencer for reducing the exhaust volume is also known.

  Here, when the PM collection device, the NOx purification device, and the silencer that constitute the exhaust gas aftertreatment device are arranged in a straight line, a long linear installation space is required around the engine. However, it is difficult to secure a long linear installation space around the engine. Therefore, as a conventional technique, the exhaust gas aftertreatment device is divided into a first exhaust gas aftertreatment device and a second exhaust gas aftertreatment device, and the two exhaust gas aftertreatment devices are arranged in a substantially horizontal direction. The arrangement is known (see, for example, Patent Document 1).

JP 2009-103016 A

  By the way, when the two exhaust gas aftertreatment devices are arranged side by side in a substantially horizontal direction as in Patent Document 1 described above, a large installation space in the horizontal direction is required around the engine. However, with a hydraulic excavator, it is difficult to ensure a large installation space in the horizontal direction around the engine. In particular, in recent hydraulic excavators, when the upper swing body is swung, the upper swing body is reduced in size so that the counterweight and the like behind do not interfere with surrounding obstacles. It is very difficult to arrange the devices side by side in the horizontal direction.

  The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to provide a construction machine that can efficiently arrange two exhaust gas aftertreatment devices in a limited space around the engine. There is to do.

A construction machine according to the present invention includes a self-propelled vehicle body, an engine mounted on the vehicle body and having an exhaust port, and one side in the length direction is a pump mounting portion, and a hydraulic pressure mounted on the pump mounting portion of the engine pump and an exhaust pipe connected to an exhaust port of the engine, and an exhaust gas aftertreatment device provided on the outlet side of the exhaust pipe, the exhaust gas after-treatment device, after the first exhaust gas A processing apparatus , a connection pipe connected to the exhaust port of the first exhaust gas aftertreatment apparatus , and a second exhaust gas aftertreatment apparatus provided on the outlet side of the connection pipe .

Then, in order to solve the above problems, characteristic of the structure of the invention of claim 1 is employed, the pump mounting portion of the engine mounting base is provided you located above the hydraulic pump, the mounting base is used, the number and mounting member attached to the pump mounting portion of the engine, and a base member formed of a back plate extending from the end edge of the lower plate and the lower plate to the upper extending horizontally provided on the mounting member and, pre-Sharing, ABS gas aftertreatment device, the first exhaust gas after-treatment device and the second exhaust gas after-treatment device and the upper so as to be parallel to each other, in the horizontal direction become heavy downward It said platform and said lower plate side of the member is fixed to said back plate side, the front Kise' connection pipe, the first exhaust gas aftertreatment device axis and the second exhaust gas while extending The first exhaust gas aftertreatment between the upper and lower directions of the axis of the aftertreatment device. Device and the second exhaust gas after-treatment device and extends parallel lies in where the structure is arranged.

According to a second aspect of the present invention, the mounting base is further provided with a first bracket provided on the lower plate for mounting the first exhaust gas aftertreatment device, and provided on the back plate after the second exhaust gas. And a second bracket for mounting the processing device.

According to a third aspect of the present invention, in the state where the axial center of the first exhaust gas aftertreatment device and the axial center of the second exhaust gas aftertreatment device are connected by a straight line, the connecting pipe is deviated from the straight line. In other words, the arrangement is such that the position is arranged with the center as the axis.

According to the first aspect of the present invention, the first exhaust gas aftertreatment device and the second exhaust gas aftertreatment device are connected to the attachment base located on the upper side of the hydraulic pump and attached to the pump attachment portion of the engine. It is arranged in a state where it is connected by a pipe and stacked in the upper and lower direction. The first exhaust gas aftertreatment device and the second exhaust gas aftertreatment device are fixed to the lower plate side and the back plate side that constitute the base member of the mounting base. Thereby, a space for installing one exhaust gas aftertreatment device can be secured , and a second exhaust gas aftertreatment device can be installed using the space above it. Furthermore, one aftertreatment unit can be formed by assembling the first and second exhaust gas aftertreatment devices and the connecting pipe to the attachment base, and this aftertreatment unit can be attached to the pump attachment portion of the engine.

  Therefore, when installing an exhaust gas aftertreatment device around an engine where it is difficult to secure a large installation space, it is only necessary to secure an installation space for one exhaust gas aftertreatment device. Two exhaust gas aftertreatment devices can be installed.

  As a result, since the two exhaust gas aftertreatment devices can be efficiently arranged in a limited space around the engine, the vehicle body can be downsized and the working performance of the construction machine can be improved. On the other hand, since the first and second exhaust gas aftertreatment devices and the connecting pipe are assembled to the attachment base to form the aftertreatment unit, it is only necessary to attach this aftertreatment unit to the pump mounting portion of the engine. Can be improved.

Also , the first exhaust gas aftertreatment device and the second exhaust gas aftertreatment device are arranged in parallel, and the connecting pipe is connected to the axis of the first exhaust gas aftertreatment device and the second exhaust gas aftertreatment device . The first and second exhaust gas aftertreatment devices are arranged so as to extend in parallel with the first and second exhaust gas aftertreatment devices between the upper and lower directions of the axis . As a result, the first and second exhaust gas aftertreatment devices and the connecting pipe can be arranged in an orderly manner without using a useless space, so that the space for installing them can be reduced.

According to the second aspect of the present invention, the first exhaust gas aftertreatment device and the second exhaust gas aftertreatment device are connected to the first bracket by connecting the first exhaust gas aftertreatment device and the second exhaust gas aftertreatment device to the first bracket. By attaching the second exhaust gas aftertreatment device to the second bracket, the aftertreatment unit can be assembled. After assembling the aftertreatment unit, the aftertreatment unit can be attached to the engine side by attaching the attachment member to the pump attachment portion of the engine.

According to the invention of claim 3 , the axial center of the connecting pipe is arranged at a position deviating from a straight line connecting the axial center of the first exhaust gas aftertreatment device and the axial center of the second exhaust gas aftertreatment device. ing. By arranging in this way, even when the connecting pipe is provided, the first exhaust gas aftertreatment device and the second exhaust gas aftertreatment device can be arranged close to each other. Thereby, the height dimension of a post-processing unit can be restrained low, and a back visual field can be made favorable.

1 is a front view showing a hydraulic excavator according to a first embodiment of the present invention. It is a top view which expands and shows the hydraulic excavator which abbreviate | omitted a part of working apparatus. It is the expanded sectional view which looked at the rear side part of the upper revolving body from the arrow III-III direction in FIG. It is the external appearance perspective view which looked at the state which attached the post-processing unit with the hydraulic pump with respect to the engine from the right rear side. It is an exploded view which shows the state which removed the aftertreatment unit from the engine. It is a front view which shows the post-processing unit by 1st Embodiment. It is the right view which looked at the post-processing unit shown in FIG. 6 from the arrow VII-VII direction. It is the left view which looked at the post-processing unit shown in FIG. 6 from arrow VIII-VIII direction. It is the external appearance perspective view which looked at the post-processing unit from the left rear side. It is the external appearance perspective view which looked at the post-processing unit from the left front side. It is an external appearance perspective view which shows a mounting base alone. It is sectional drawing which looked at the post-processing unit from the arrow XII-XII direction in FIG. It is the front view which looked at the post-processing unit by the 2nd Embodiment of this invention from the same position as FIG. It is the external appearance perspective view which looked at the post-processing unit by the reference example of this invention from the same position as FIG. It is the front view which looked at the post-processing unit by the 3rd Embodiment of this invention from the same position as FIG. It is the front view which looked at the post-processing unit by the 1st modification of this invention from the same position as FIG. It is the front view which looked at the post-processing unit by the 2nd modification of this invention from the same position as FIG. It is sectional drawing which looked at the post-processing unit by the 3rd modification of this invention from the same position as FIG.

  Hereinafter, as a representative example of a construction machine according to an embodiment of the present invention, a hydraulic excavator equipped with an engine will be taken as an example and described in detail with reference to the accompanying drawings.

  First, FIGS. 1 to 12 show a first embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a crawler hydraulic excavator as a construction machine. The hydraulic excavator 1 includes a self-propelled crawler-type lower traveling body 2, a swivel mounted on the lower traveling body 2, an upper revolving body 3 that forms a vehicle body with the lower traveling body 2, and the upper It is comprised by the working apparatus 4 which is provided in front of the revolving structure 3 and the front side of the back direction so that a vertical movement is possible, and performs the excavation work etc. of earth and sand.

  A revolving frame 5 forms a support structure for the upper revolving structure 3. As shown in FIGS. 2 and 3, the revolving frame 5 has a bottom plate 5A made of a thick steel plate or the like extending in the front and rear directions, and is erected on the bottom plate 5A and has a predetermined interval in the left and right directions. Left and right vertical plates 5B and 5C extending in the front and rear directions, and left and right side frames 5D and right extending in the front and rear directions. The frame includes a side frame 5E and a plurality of extended beams 5F that extend leftward and rightward from the bottom plate 5A and the vertical plates 5B and 5C and support the left and right side frames 5D and 5E at the front end portions thereof. Has been.

  On the front side of the revolving frame 5, the working device 4 is attached between the left and right vertical plates 5B and 5C so as to be able to move up and down. On the rear side of the turning frame 5, a counterweight 7, an engine 8, and the like, which will be described later, are provided.

  Reference numeral 6 denotes a cab (see FIG. 1) mounted on the left front side of the revolving frame 5. The cab 6 is used by an operator, and includes a driver's seat on which the operator is seated, an operating lever for traveling, An operation lever or the like for work (none of which is shown) is provided. On the other hand, 7 is a counterweight attached to the rear end portion of the revolving frame 5, and the counterweight 7 balances the weight with the work device 4.

  Reference numeral 8 denotes an engine provided on the rear side of the revolving frame 5, and the engine 8 is mounted in a horizontally placed state extending in the left and right directions. As shown in FIG. 4, a cooling fan 8 </ b> A for supplying cooling air to a heat exchanger (not shown) is provided on the left side of the engine 8. On the other hand, the right side of the engine 8 is a pump mounting portion 8B in which a plurality of female screw holes (not shown) are provided on an annular end surface. The pump mounting portion 8B includes a mounting flange of a hydraulic pump 9 described later. 9A and the mounting member 17 of the mounting base 16 are bolted. Furthermore, an exhaust port (not shown) for exhaust gas exhaust is provided in the upper part on the front side of the engine 8, and an inlet side of an exhaust pipe 14 to be described later is attached to this exhaust port in a communicating state. .

  Reference numeral 9 denotes a hydraulic pump attached to the pump attachment portion 8B of the engine 8. The hydraulic pump 9 is driven by the engine 8 to discharge hydraulic oil supplied from a hydraulic oil tank 11 described later as pressure oil toward a control valve device (not shown). The hydraulic pump 9 is provided with a mounting flange 9A by expanding the end portion on the engine 8 side into a circular shape. A plurality of bolt insertion holes (not shown) are provided on the outer peripheral side of the mounting flange 9A.

  Then, the hydraulic pump 9 has the mounting flange 9A facing the pump mounting portion 8B of the engine 8, the bolts 10 are inserted into the respective bolt insertion holes, and the bolts 10 are screwed into the female screw holes of the pump mounting portion 8B. By doing so, it is attached to the pump attachment portion 8B. On the other hand, among the bolts 10 for attaching the hydraulic pump 9 to the engine 8, the plurality of bolts 10 located on the upper side attach the attachment member 17 of the attachment base 16 constituting the aftertreatment unit 15 described later to the engine 8. It is also used in some cases.

  Here, the environment around the engine 8 will be described. The engine 8 is sandwiched between a counterweight 7 and a hydraulic oil tank 11 and the like, and a heat exchanger, a hydraulic pump 9 and the like are arranged around the engine 8, and many hoses are connected to these. ing. Therefore, it is difficult to secure a wide installation space around the engine 8 in which two exhaust gas aftertreatment devices can be arranged in the horizontal direction as in, for example, conventional Patent Document 1, and two exhaust gases. Of the aftertreatment devices, a small space for arranging one of the exhaust gas aftertreatment devices can be secured.

  Reference numeral 11 denotes a hydraulic oil tank (see FIG. 2) that is located on the right side of the revolving frame 5 and is located on the front side of the hydraulic pump 9. The hydraulic oil tank 11 is provided in the lower traveling body 2, the work device 4, and the like. The hydraulic oil for driving the actuator is stored. On the other hand, reference numeral 12 denotes a fuel tank provided on the revolving frame 5 located on the front side of the hydraulic oil tank 11.

  A building cover 13 covers equipment including the engine 8, the heat exchanger, and a post-processing unit 15 described later from the side and from above. The building cover 13 is provided on the revolving frame 5 between the cab 6 and the counterweight 7. As shown in FIGS. 2 and 3, the building cover 13 includes a left side cover part 13A covering the left side of the heat exchanger and the like, a right side cover part 13B covering the right side of the hydraulic pump 9 and the like, and each of the cover parts 13A and 13B. An upper surface cover portion 13 </ b> C that is located on the upper side and covers the upper side of the engine 8, the post-processing unit 15, etc.

  The upper surface cover portion 13C is provided with a post-processing cover portion 13D that is located on the right side in the left and right directions, specifically on the upper side of the post-processing unit 15. The post-processing cover portion 13D covers a second exhaust gas post-processing device 26, which will be described later, forming a part of the post-processing unit 15, and the second exhaust gas post-processing device 26 protruding from the upper surface cover portion 13C. Is formed as a box-like body opened downward. The post-processing cover portion 13D is provided with an opening 13D1 for projecting a tail tube 30 described later upward. The tail pipe may be integrally attached to the post-processing cover portion, and a discharge pipe extending from the second exhaust gas after-treatment device may be connected to the tail pipe.

  Reference numeral 14 denotes an exhaust pipe (see FIGS. 3 and 5) provided between the engine 8 and a first exhaust gas aftertreatment device 21 described later. The exhaust pipe 14 has one end on the inlet side connected to the exhaust port of the engine 8, and the other end on the outlet side connected to the air supply port 22 </ b> A of the cylindrical case 22 constituting the first exhaust gas aftertreatment device 21. It is connected.

  Next, in order to process the exhaust gas discharged from the engine 8, the configuration of the post-processing unit 15 connected to the exhaust side of the engine 8 will be described with reference to FIGS.

  Reference numeral 15 denotes a post-processing unit according to the first embodiment which is located on the right side of the engine 8 and provided above the hydraulic pump 9. The aftertreatment unit 15 oxidizes and removes carbon monoxide (CO), hydrocarbons (HC), etc. contained in the exhaust gas discharged from the engine 8, and removes nitrogen oxides (NOx) contained in the exhaust gas. It purifies and further reduces the noise of the exhaust gas. The aftertreatment unit 15 includes a mounting base 16, a first exhaust gas aftertreatment device 21, a connecting pipe 24, and a second exhaust gas aftertreatment device 26 which will be described later. As shown in FIGS. 4 and 5, the aftertreatment unit 15 is assembled with the first exhaust gas aftertreatment device 21, the connecting pipe 24, and the second exhaust gas aftertreatment device 26 attached to the mounting base 16. The mounting base 16 is mounted on the engine 8.

  Reference numeral 16 denotes a mounting base that forms a mounting base for the post-processing unit 15. The mounting base 16 is positioned above the hydraulic pump 9 and is mounted on the pump mounting portion 8B of the engine 8. The attachment base 16 is for fixedly attaching the first exhaust gas aftertreatment device 21 and the second exhaust gas aftertreatment device 26 to the engine 8 side. As shown in FIG. 11, the mounting base 16 includes a mounting member 17 facing the pump mounting portion 8B of the engine 8 across the mounting flange 9A of the hydraulic pump 9, and a base member 18 provided on the mounting member 17. The first and second brackets 19 and 20 are provided on the base member 18.

  The mounting member 17 is in contact with the mounting flange 9A of the hydraulic pump 9, and is formed as a rectangular plate extending in the front and rear directions of the upper swing body 3. An arcuate cutout 17A for avoiding the hydraulic pump 9 is formed in the lower portion of the mounting member 17, and a plurality of, for example, six bolt insertion holes 17B are formed around the cutout 17A. Yes. These bolt insertion holes 17B are provided in the pump mounting portion 8B of the engine 8 and therefore correspond to screw holes and bolt insertion holes provided in the mounting flange 9A of the hydraulic pump 9, and are 5 or less, or 7 or more. It is good also as a structure to provide.

  The base member 18 includes, for example, a lower plate 18A extending in the horizontal direction by bending a rectangular plate body into an L shape, and a back plate 18B extending upward from the left edge (engine 8 side) of the lower plate 18A. And have. The base member 18 has the lower surface of the lower plate 18A fixed to the upper end edge of the mounting member 17 using welding means or the like so that the back plate 18B extends in the front and rear directions of the upper swing body 3. Further, a plurality of reinforcing plates 18 </ b> C are provided between the lower plate 18 </ b> A and the attachment member 17.

  Two first brackets 19 are erected on the upper surface of the lower plate 18A of the base member 18 at intervals in the front and rear directions. The upper edge of the two first brackets 19 is a concave arc mounting recess 19A so that the cylindrical case 22 of the first exhaust gas aftertreatment device 21 can be stably mounted.

  Further, the second bracket 20 is positioned above the back plate 18B of the base member 18 and is erected on its surface (surface on the side opposite to the engine 8) with an interval in the front and rear directions. The tip edges of the two second brackets 20 are concave concave mounting portions 20A so that the cylindrical case 27 of the second exhaust gas aftertreatment device 26 can be stably mounted.

  Here, the first bracket 19 is arranged so as to extend the cylindrical case 22 of the first exhaust gas aftertreatment device 21 in the front and rear directions, and the second bracket 20 is provided with the second exhaust gas. The cylindrical case 27 of the post-processing device 26 is arranged so as to extend in the front and rear directions. Therefore, as shown in FIG. 7, the brackets 19 and 20 have the cylindrical cases 22 and 27 of the exhaust gas aftertreatment devices 21 and 26 with the central axes O1-O1 and O3-O3 as the front and rear directions, respectively. It can be placed parallel to the upper and lower positions.

  As shown in FIG. 5, the mounting base 16 formed in this way places the mounting member 17 on the mounting flange 9 </ b> A of the hydraulic pump 9, for example, when the hydraulic pump 9 is mounted on the engine 8. Each bolt 10 inserted through the hole 17B is screwed into each female screw hole provided in the pump mounting portion 8B of the engine 8, so that it can be mounted together with the mounting flange 9A (in the tightened state) to the pump mounting portion 8B. it can.

  Reference numeral 21 denotes a first exhaust gas aftertreatment device that constitutes a part of the aftertreatment unit 15. The first exhaust gas aftertreatment device 21 is provided on the outlet side of the exhaust pipe 14. As shown in FIG. 12, the first exhaust gas aftertreatment device 21 is disposed in a cylindrical case 22 extending in front and rear of the upper swing body 3, and in the cylindrical case 22. And an oxidation catalyst 23. The oxidation catalyst 23 constitutes one of the processing members for purifying the exhaust gas. For example, the oxidation catalyst 23 is formed of a ceramic cell-like cylinder, and has a large number of through holes formed in the axial direction thereof. Is coated. The oxidation catalyst 23 oxidizes and removes carbon monoxide (CO), hydrocarbons (HC), etc. contained in the exhaust gas by circulating the exhaust gas through each through hole at a predetermined temperature. It is.

  The cylindrical case 22 is formed as a sealed container by closing both ends of a cylindrical body having an axis O1-O1. An air supply port 22 </ b> A made of a tubular body extending in the radial direction of the cylindrical case 22 is provided in a front side portion that is the upstream side of the cylindrical case 22. The air supply port 22A has one end in the length direction inserted into the cylindrical case 22 and the other end protruding outward in the radial direction. Further, the air supply port 22A is provided with a plurality of through holes (not shown) located in the cylindrical case 22 in substantially the same manner as the tail tube 30 of the second exhaust gas aftertreatment device 26 described later. As the exhaust gas passes through the through holes, the exhaust noise is reduced (silenced). On the other hand, the outlet side of the exhaust pipe 14 is connected to the protruding end side of the air supply port 22A.

  Further, an exhaust port 22B is provided in the rear side portion, which is the downstream side of the cylindrical case 22, and is provided with an exhaust port 22B. The exhaust port 22B is connected to the inlet side of the connection pipe 24. The exhaust port 22B is rotated by a desired angle (for example, a range of about 10 to 60 degrees) from the position directly above the cylindrical case 22 to the engine 8 side when the air supply port 22A is disposed toward the engine 8 side. Open at the position.

  In the first exhaust gas aftertreatment device 21, the cylindrical case 22 is placed on each first bracket 19 of the mounting base 16, and in this state, a fastening band, a bolt, or the like (not shown) is used. It is fixed to the mounting base 16. Thus, the axis O1-O1 of the cylindrical case 22 is in the front and rear directions of the upper swing body 3.

  Reference numeral 24 denotes a connecting pipe connected to the exhaust port 22B of the cylindrical case 22 constituting the first exhaust gas aftertreatment device 21. The connection pipe 24 is disposed between the first exhaust gas aftertreatment device 21 and a second exhaust gas aftertreatment device 26 described later. The connecting pipe 24 includes a cylindrical portion 24A made of a cylindrical body having an axis O2-O2, an upstream cover plate 24B that closes an inlet edge on the upstream side of the cylindrical portion 24A, and a downstream side of the cylindrical portion 24A. It is comprised by the downstream cover plate 24C which obstruct | occludes the edge of the exit side used as the side.

  The connection pipe 24 has an inlet side (rear side) connected to an exhaust port 22B of the cylindrical case 22 constituting the first exhaust gas post-treatment device 21, and an outlet side (front side) of a second exhaust gas post-treatment described later. It is connected to an air supply port 27 </ b> A of a cylindrical case 27 that forms the device 26. Thereby, the connection pipe 24 can guide the exhaust gas discharged from the first exhaust gas aftertreatment device 21 to the second exhaust gas aftertreatment device 26.

  Here, the connecting pipe 24 is arranged so that its axis O2-O2 is parallel to the axis O1-O1 of the first exhaust gas aftertreatment device 21 and the axis O3-O3 of the second exhaust gas aftertreatment device 26. , Extending in the rearward direction. Further, as shown in FIG. 6, the connecting pipe 24 is connected to a straight line O1-O3 connecting the axial center O1 of the first exhaust gas aftertreatment device 21 and the axial center O3 of the second exhaust gas aftertreatment device 26. The position deviated from the straight line O1-O3 is arranged as the axial center O2.

  That is, the connecting pipe 24 is disposed at a position separated from the straight line O1-O3 by the length dimension L1 on the engine 8 side. Thereby, even when the connecting pipe 24 is provided between the first exhaust gas aftertreatment device 21 and the second exhaust gas aftertreatment device 26, the first exhaust gas aftertreatment device 21 and the second exhaust gas are provided. The aftertreatment device 26 can be disposed close to the second exhaust gas aftertreatment device 26, and the height dimension of the second exhaust gas aftertreatment device 26 can be kept low.

  Reference numeral 25 denotes a urea water injection nozzle provided in the connecting pipe 24. The urea water injection nozzle 25 constitutes a part of the NOx purification device. The urea water injection nozzle 25 is attached to the upstream lid plate 24B of the connection pipe 24, and is connected to a urea water tank for storing a urea aqueous solution via a pump (both not shown). The urea water injection nozzle 25 injects the urea aqueous solution toward the exhaust gas flowing through the cylindrical portion 24A.

  Reference numeral 26 denotes a second exhaust gas aftertreatment device that constitutes a part of the aftertreatment unit 15. The second exhaust gas aftertreatment device 26 is provided on the outlet side of the connecting pipe 24 and is disposed at a position overlapping the upper side of the first exhaust gas aftertreatment device 21. The second exhaust gas aftertreatment device 26 is substantially the same as the first exhaust gas aftertreatment device 21 described above, and includes a cylindrical case 27 extending in the front and rear directions of the upper swing body 3 and the cylindrical shape. A selective reduction catalyst 28 that is disposed in the case 27 and selectively decomposes nitrogen oxide (NOx) with ammonia to decompose it into water and nitrogen, and is disposed on the downstream side of the selective reduction catalyst 28. An oxidation catalyst 29 that oxidizes residual ammonia remaining after reducing the nitrogen oxides by the catalyst 28 and separates it into nitrogen and water, and projects upward from the cylindrical case 27 located downstream of the oxidation catalyst 29. The tail tube 30 is configured.

  As shown in FIG. 7, the cylindrical case 27 of the second exhaust gas aftertreatment device 26 is a cylinder having an axis O3-O3, similar to the cylindrical case 22 of the first exhaust gas aftertreatment device 21. It is formed as a sealed container by closing both ends of the body. An air supply port 27 </ b> A is provided in the front side portion, which is the upstream side of the cylindrical case 27, so as to open in the radial direction, and the outlet side of the connection pipe 24 is connected to the air supply port 27 </ b> A.

  The air supply port 27A of the cylindrical case 27 opens at a position rotated from the position directly below the cylindrical case 27 toward the engine 8 by a desired angle (for example, in a range of about 10 to 60 degrees). Thereby, the connection pipe 24 connected to the exhaust port 22B of the cylindrical case 22 and the air supply port 27A of the cylindrical case 27 is connected to the first exhaust gas post-processing device 21 and the second exhaust gas post-processing device 26. It can be placed at a position avoiding the gap.

  The selective reduction catalyst 28 is made of, for example, a ceramic tubular body made of ceramics. A large number of through holes are formed in the axial direction, and the inner surface is coated with a noble metal. This selective reduction catalyst 28 is a catalyst that selectively reduces nitrogen oxide (NOx) contained in the exhaust gas discharged from the engine 8 by ammonia generated from the urea aqueous solution, and decomposes it into nitrogen and water. It is.

  On the other hand, the oxidation catalyst 29 is formed of a ceramic cell-like cylindrical body in substantially the same manner as the oxidation catalyst 23 described above. A large number of through holes are formed in the axial direction, and the inner surface is coated with a noble metal. Thereby, the oxidation catalyst 29 oxidizes the residual ammonia remaining after reducing the nitrogen oxides by the selective reduction catalyst 28 and separates it into nitrogen and water.

  Further, the tail tube 30 is located at a rear side portion that is downstream of the cylindrical case 27 (downstream of the oxidation catalyst 29), one end in the length direction is inserted into the cylindrical case 27, and the other end has a diameter. Projects upward in the direction. A large number of through holes 30A are provided in the lower portion of the tail tube 30 that has entered the cylindrical case 27, and exhaust gas passes through each of the through holes 30A, so that exhaust noise is reduced (silenced). The On the other hand, the upper part of the tail tube 30 protruding from the cylindrical case 27 is bent rearward to serve as an exhaust gas outlet.

  In the second exhaust gas aftertreatment device 26, a cylindrical case 27 is fixed to each second bracket 20 of the mounting base 16 using a fastening band, a bolt, or the like (all not shown). As a result, the second exhaust gas aftertreatment device 26 is arranged at a position overlapping the upper side of the first exhaust gas aftertreatment device 21, and its axis O 3 -O 3 is the axis of the first exhaust gas aftertreatment device 21. It is parallel to O1-O1.

  Parallel in this case is not limited to complete parallelism, but includes a state in which the axis O1-O1 and the axis O3-O3 are slightly inclined and arranged in parallel, and in a range that can be seen almost in parallel. As stated. On the other hand, the first exhaust gas aftertreatment device 21 and the second exhaust gas aftertreatment device 26 are disposed at positions where they overlap completely in the upper and lower directions (they overlap each other by 100%). However, the position overlapping in the upward and downward directions is that the majority of both, for example, 70% or more overlap.

  Next, an example of the assembly procedure of the post-processing unit 15 and the attachment procedure to the engine 8 according to the first embodiment will be described.

  In the assembly work of the aftertreatment unit 15, the cylindrical case 22 of the first exhaust gas aftertreatment device 21 and the cylindrical case 27 of the second exhaust gas aftertreatment device 26 are connected by the connecting pipe 24. In this state, the cylindrical case 22 of the first exhaust gas aftertreatment device 21 is placed on each first bracket 19 of the mounting base 16, and the cylindrical case 22 is mounted on the base member using fastening bands, bolts, or the like. 18 is fixed to the lower plate 18A. Similarly, the cylindrical case 27 of the second exhaust gas aftertreatment device 26 is fixed to each second bracket 20 (back plate 18B of the base member 18) of the mounting base 16. Thereby, the 1st exhaust gas aftertreatment device 21 and the 2nd exhaust gas aftertreatment device 26 can be arranged in the position which overlaps in the up and down direction.

  After the first and second exhaust gas aftertreatment devices 21 and 26 are assembled to the attachment base 16, the aftertreatment unit 15 is attached to the engine 8. In this mounting operation, as shown in FIGS. 4 and 5, the mounting member 17 is brought into contact with the mounting flange 9 </ b> A of the hydraulic pump 9, and in this state, each bolt 10 inserted into each bolt insertion hole 17 </ b> B is pumped to the engine 8. By screwing into each female screw hole provided in the mounting portion 8B, it is mounted on the pump mounting portion 8B together with the mounting flange 9A. Further, the air supply port 22 </ b> A of the cylindrical case 22 of the first exhaust gas aftertreatment device 21 is connected to the outlet side of the exhaust pipe 14. Thereby, the post-processing unit 15 can be attached to the engine 8.

  Next, the operation (operation) of the excavator 1 to which the first embodiment is applied will be described.

  An operator boarding the cab 6 starts the engine 8 and drives the hydraulic pump 9. Thereby, the pressure oil from the hydraulic pump 9 is supplied to various actuators via the control valve device. Thereby, when the operator operates the operation lever (not shown) for traveling, the lower traveling body 2 can be moved forward or backward. On the other hand, by operating a working operation lever (not shown), the work device 4 and the like can be operated to perform excavation work of earth and sand.

  Here, during operation of the engine 8, exhaust gas discharged from the engine 8 passes through the exhaust pipe 14, the first exhaust gas aftertreatment device 21, the connection pipe 24, and the second exhaust gas aftertreatment device 26 into the atmosphere. To be discharged. At this time, the oxidation catalyst 23 provided in the first exhaust gas aftertreatment device 21 oxidizes and removes carbon monoxide (CO), hydrocarbon (HC), etc. contained in the exhaust gas. On the other hand, the connecting pipe 24 injects urea water from the urea water injection nozzle 25 toward the exhaust gas, and the second exhaust gas aftertreatment device 26 decomposes nitrogen oxides into nitrogen and water by the selective reduction catalyst 28. . Further, the oxidation catalyst 29 oxidizes residual ammonia and separates it into nitrogen and water, so that the purified exhaust gas is discharged into the atmosphere.

  Thus, according to the first embodiment, the mounting base 16 is located on the upper side of the hydraulic pump 9 and is attached to the pump mounting portion 8B of the engine 8. The mounting base 16 includes the first exhaust gas. The aftertreatment device 21 and the second exhaust gas aftertreatment device 26 are arranged so as to be overlapped in the upper and lower directions in a state where they are connected by the connection pipe 24. The mounting base 16, the first and second exhaust gas aftertreatment devices 21 and 26, and the connecting pipe 24 are attached to the pump attachment portion 8 </ b> B of the engine 8 as one aftertreatment unit 15.

  Therefore, by arranging the first exhaust gas aftertreatment device 21 and the second exhaust gas aftertreatment device 26 so as to overlap each other even in the vicinity of the engine 8 where it is difficult to secure a wide installation space, For example, only by securing a space for installing the first exhaust gas aftertreatment device 21, two exhaust gas aftertreatment devices 21 and 26 can be provided in this small installation space.

  As a result, since the two exhaust gas aftertreatment devices 21 and 26 can be efficiently arranged in a limited space around the engine 8, it is possible to reduce the size of the upper swing body 3 and perform work on a narrow work site. It is possible to improve the work performance of the excavator 1.

  On the other hand, the first and second exhaust gas aftertreatment devices 21 and 26 and the connection pipe 24 are assembled to the mounting base 16 to form the aftertreatment unit 15. Thereby, in the production line, it is only necessary to attach the pre-processed post-processing unit 15 to the pump attachment portion 8B of the engine 8, so that productivity can be improved.

  After the first exhaust gas aftertreatment device 21 and the second exhaust gas aftertreatment device 26 are arranged in parallel, the connecting pipe 24 is connected to the first exhaust gas aftertreatment device 21 and the second exhaust gas aftertreatment. The first and second exhaust gas aftertreatment devices 21 and 26 are arranged so as to extend in parallel with the device 26. As a result, the first and second exhaust gas aftertreatment devices 21 and 26 and the connection pipe 24 can be arranged in an orderly manner without forming a useless space, so that the space for installing them is reduced. be able to. As a result, further downsizing of the upper swing body 3 can be achieved.

  On the other hand, the mounting base 16 includes a mounting member 17 mounted on the pump mounting portion 8B of the engine 8, a lower plate 18A provided on the mounting member 17 and extending horizontally, and a back extending upward from an edge of the lower plate 18A. A base member 18 made of a plate 18B, a first bracket 19 for mounting the first exhaust gas aftertreatment device 21 provided on the lower plate 18A, and a second exhaust gas aftertreatment device 26 provided on the back plate 18B. And a second bracket 20 for mounting.

  Therefore, with the first exhaust gas aftertreatment device 21 and the second exhaust gas aftertreatment device 26 connected by the connecting pipe 24, the first exhaust gas aftertreatment device 21 is attached to the first bracket 19, By attaching the second exhaust gas aftertreatment device 26 to the second bracket 20, the aftertreatment unit 15 can be assembled. When the post-processing unit 15 is assembled, the post-processing unit 15 can be mounted on the engine 8 side by mounting the mounting member 17 on the pump mounting portion 8B of the engine 8. In this attached state, the first exhaust gas aftertreatment device 21 and the second exhaust gas aftertreatment device 26 can be arranged so as to overlap in the upward and downward directions.

  Further, a straight line connecting the axial center O1 of the first exhaust gas aftertreatment device 21 and the axial center O3 of the second exhaust gas aftertreatment device 26 is defined as a straight line O1-O3. A position deviating from O3 is arranged as the axis center O2. Thereby, even when the connecting pipe 24 is provided between the first exhaust gas aftertreatment device 21 and the second exhaust gas aftertreatment device 26, the first exhaust gas aftertreatment device 21 and the second exhaust gas are provided. The post-processing device 26 can be disposed close to the post-processing device 26. As a result, the height dimension of the aftertreatment unit 15 (second exhaust gas aftertreatment device 26) can be kept low, and the rear visibility can be improved.

  Next, FIG. 13 shows a second embodiment of the present invention. The feature of the present embodiment is that the axial center of the connecting pipe deviates from the engine on the opposite side to the straight line connecting the axial center of the first exhaust gas aftertreatment device and the axial center of the second exhaust gas aftertreatment device. The configuration is arranged at a certain position. In the present embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and the description thereof is omitted.

  In FIG. 13, reference numeral 41 denotes a post-processing unit according to the second embodiment. This post-processing unit 41 is substantially the same as the post-processing unit 15 according to the first embodiment described above, the mounting base 42, the first exhaust gas post-processing device 43, the connection pipe 44, the second exhaust gas post-processing. The apparatus 45 is comprised. However, the post-processing unit 41 according to the second embodiment is different from the first embodiment in that the connecting pipe 44 is arranged on the opposite side to the engine 8 with respect to the exhaust gas post-processing devices 43 and 45. This is different from the post-processing unit 15 according to the embodiment.

  In other words, the connecting pipe 44 according to the second embodiment is configured such that the engine extends from the straight line O4-O6 connecting the axial center O4 of the first exhaust gas aftertreatment device 43 and the axial center O6 of the second exhaust gas aftertreatment device 45. A position separated by a length dimension L2 is disposed on the opposite side of 8 as the axial center O5.

  Thus, also in the second embodiment configured as described above, it is possible to obtain substantially the same operational effects as those of the first embodiment described above. In particular, in the second embodiment, even when the connection pipe 44 is provided between the first exhaust gas post-treatment device 43 and the second exhaust gas post-treatment device 45, the connection pipe 44 can be shifted and arranged. Thus, the first exhaust gas aftertreatment device 43 and the second exhaust gas aftertreatment device 45 can be arranged close to each other, and the height dimension of the aftertreatment unit 41 can be kept low.

Next, FIG. 14 shows a reference example of the present invention. The reference example of the present invention is that the first exhaust gas aftertreatment device and the second exhaust gas aftertreatment device are connected by a short connecting pipe. In this reference example , the same components as those in the first embodiment described above are denoted by the same reference numerals, and description thereof is omitted.

In FIG. 14, reference numeral 51 denotes a post-processing unit according to a reference example . Reference numeral 52 denotes a mounting base for the post-processing unit 51. The mounting base 52 is substantially the same as the mounting base 16 according to the first embodiment described above, and includes a mounting member 53, a base member 54, a first bracket 55, a second bracket. The bracket 56 is used. However, the mounting base 52 according to the reference example is different from the mounting base 16 according to the first embodiment in that the height dimension of the back plate 54B of the base member 54 is formed low.

  Reference numeral 57 denotes a first exhaust gas aftertreatment device provided on the lower plate 54A of the base member 54 of the mounting base 52. Reference numeral 58 denotes a connecting pipe provided so as to protrude upward on the downstream side of the first exhaust gas aftertreatment device 57. Further, 59 is a second exhaust gas aftertreatment device whose upstream side is connected to the upper portion of the connecting pipe 58. The connection pipe 58 connects the rear portion of the first exhaust gas aftertreatment device 57 and the rear portion of the second exhaust gas aftertreatment device 59 at a short distance. The connecting pipe 58 is provided with the urea water injection nozzle 25, and the tail pipe 30 is provided at a front portion which is downstream of the second exhaust gas aftertreatment device 59.

Thus, in the reference example thus configured, the connection pipe 58, without forming extends parallel to the respective exhaust gas aftertreatment device 21, 26 as connecting tube 24 according to the first embodiment, Since it is formed in a short length, the first exhaust gas aftertreatment device 57 and the second exhaust gas aftertreatment device 59 can be arranged so as to overlap in the upward and downward directions in a state of being close to each other. As a result, the height dimension of the post-processing unit 51 can be kept low, and the rear view can be improved.

Next, FIG. 15 shows a third embodiment of the present invention. The feature of this embodiment is that the aftertreatment unit is constituted by an exhaust pipe, a mounting base, a first exhaust gas aftertreatment device, a connecting pipe, and a second exhaust gas aftertreatment device. In the present embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and the description thereof is omitted.

In FIG. 15, reference numeral 61 denotes a post-processing unit according to the third embodiment. The post-treatment unit 61 is substantially the same as the post-treatment unit 15 according to the first embodiment described above, and the mounting base 16, the first exhaust gas after-treatment device 21, the connection pipe 24, and the second exhaust gas after-treatment. The device 26 is configured. However, the post-processing unit 61 according to the third embodiment is different from the post-processing unit 15 according to the first embodiment in that it includes the exhaust pipe 14.

That is, in the aftertreatment unit 61 according to the third embodiment, the exhaust pipe 14 is attached to the air supply port 22A of the cylindrical case 22 constituting the first exhaust gas aftertreatment device 21, and this exhaust gas is exhausted. It is unitized including the tube 14. When the post-processing unit 61 is assembled on the engine 8 side, the inlet side of the exhaust pipe 14 may be connected to the exhaust port of the engine 8.

Thus, also in the third embodiment configured as described above, it is possible to obtain substantially the same operational effects as those of the first embodiment described above. In particular, in the third embodiment, since the exhaust pipe 14 is added to the post-processing unit 61, it is possible to reduce the number of parts that can be assembled on the engine 8 side where piping and wiring are complicated and difficult to work. Can be improved.

  In the first embodiment, the aftertreatment unit 15 is a state in which the axial center O1 of the first exhaust gas aftertreatment device 21 and the axial center O3 of the second exhaust gas aftertreatment device 26 are connected by a straight line. The case where the connecting pipe 24 is arranged with the position deviating from the straight line O1-O3 toward the engine 8 as the axis center O2 has been described as an example. However, the present invention is not limited to this. For example, the present invention may be configured as a first modification shown in FIG.

  That is, a post-processing unit 71 according to the first modification shown in FIG. 16 may be configured. The aftertreatment unit 71 is configured such that a first exhaust gas aftertreatment device 73, a connecting pipe 74, and a second exhaust gas aftertreatment device 75 are arranged on the mounting base 72 so as to overlap in the upward and downward directions. With this configuration, the space required for installing the post-processing unit 71 can be further reduced.

  On the other hand, you may comprise like the post-processing unit 81 by the 2nd modification shown in FIG. The post-processing unit 81 includes a mounting base 82, a first exhaust gas post-processing device 83, a connecting pipe 84, and a second exhaust gas post-processing device 85. Although the first exhaust gas aftertreatment device 83, the connecting pipe 84, and the second exhaust gas aftertreatment device 85 are arranged in parallel to each other, the second exhaust gas aftertreatment device 85 is provided with the first exhaust gas. The gas after-treatment device 83 is disposed at a position shifted to the opposite side to the engine 8. This configuration can be similarly applied to other embodiments.

  In the first embodiment, the case where only the oxidation catalyst 23 is provided in the cylindrical case 22 of the first exhaust gas aftertreatment device 21 has been described as an example. However, the present invention is not limited to this. For example, the present invention may be configured as a third modification shown in FIG. In this third modification, a particulate matter removal filter 91 (Diesel Particulate Filter, abbreviated as DPF) is located in the cylindrical case 22 of the first exhaust gas aftertreatment device 21 and downstream of the oxidation catalyst 23. Called). This particulate matter removing filter 91 purifies the exhaust gas by collecting particulate matter (PM) in the exhaust gas discharged from the engine 8 and burning and removing it. This configuration can be similarly applied to other embodiments.

  Furthermore, in each embodiment, the hydraulic excavator 1 provided with the crawler type lower traveling body 2 was 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, it can be widely applied to other construction machines such as wheel loaders, dump trucks, hydraulic cranes and the like.

1 Excavator (construction machine)
2 Lower traveling body (car body)
3 Upper swing body (car body)
DESCRIPTION OF SYMBOLS 5 Turning frame 8 Engine 9 Hydraulic pump 9A Mounting flange 10 Bolt 14 Exhaust pipe 15,41,51,61,71,81 Post-processing unit 16,42,52,72,82 Mounting base 17,53 Mounting member 18,54 units Members 18A, 54A Lower plate 18B, 54B Back plate 19, 55 First bracket 20, 56 Second bracket 21, 43, 57, 73, 83 First exhaust gas aftertreatment device 22, 27 Cylindrical case 22A, 27A Air supply port 22B Exhaust port 23, 29 Oxidation catalyst 24, 44, 58, 74, 84 Connection pipe 25 Urea water injection nozzle 26, 45, 59, 75, 85 Second exhaust gas aftertreatment device 28 Selective reduction catalyst 91 Particulate matter removal filter O1-O1 axis of first exhaust gas aftertreatment device (axis center)
O2-O2 connecting pipe axis (axis center)
O3-O3 Second exhaust gas aftertreatment axis (axis center)
O4 Axis center of the first exhaust gas aftertreatment device O5 Axis center of the connection tube O6 Axis center of the second exhaust gas aftertreatment device L1, L2 Spacing dimensions of the connection tube

Claims (3)

A self-propelled vehicle body, an engine mounted on the vehicle body and having an exhaust port and having a pump attachment portion on one side in the length direction, a hydraulic pump attached to the pump attachment portion of the engine, and an exhaust of the engine comprising an exhaust pipe connected to the mouth, and exhaust gas aftertreatment device provided on the outlet side of the exhaust pipe,
The exhaust gas aftertreatment device includes a first exhaust gas aftertreatment device , a connection pipe connected to the exhaust port of the first exhaust gas aftertreatment device , and a second pipe provided on the outlet side of the connection pipe. In a construction machine configured with an exhaust gas aftertreatment device of
The pump mounting portion of the engine mounting base is provided you located above the hydraulic pump,
Said mounting base includes a mounting member attached to the pump mounting portion of the engine, and the base member comprising a back plate extending from the end edge of the lower plate and the lower plate to the upper extending horizontally provided on the mounting member Have
Before Sharing, ABS gas aftertreatment device, the first exhaust gas after-treatment device and the second exhaust gas after-treatment device and the upper so as to be parallel to each other, extending in the horizontal direction become heavy downward Is fixed to the lower plate side and the back plate side of the base member,
Before Kise' connection tube, on the axis of the first exhaust gas aftertreatment device axis and the second exhaust gas aftertreatment device, between the downward direction, the first exhaust gas after-treatment device and the A construction machine characterized in that the construction machine is configured to extend in parallel with the exhaust gas aftertreatment device . Before Symbol mounting base is further attached a first bracket provided on the lower plate mounting the first exhaust gas after-treatment device, the second exhaust gas after-treatment device is provided in the back plate first The construction machine according to claim 1, comprising two brackets. In a state where the axial center of the first exhaust gas aftertreatment device and the axial center of the second exhaust gas aftertreatment device are connected by a straight line, the connecting pipe is arranged with the position deviating from the straight line as the axial center. The construction machine according to claim 1 or 2 , wherein the construction machine is configured as described above.

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