WO2015012169A1

WO2015012169A1 - Working vehicle

Info

Publication number: WO2015012169A1
Application number: PCT/JP2014/068906
Authority: WO
Inventors: 雄作岡村; 義秋黒川
Original assignee: ヤンマー株式会社
Priority date: 2013-07-23
Filing date: 2014-07-16
Publication date: 2015-01-29

Abstract

The present invention addresses the problem of providing a working vehicle such that manufacturing cost can be reduced through miniaturization and simplification of a case-supporting base (121) and such that the support rigidity of a second case (63) and the like can be easily improved. This working vehicle is equipped with a cab section (7) in which the operator will be located, a first case (62) for removing particulate matter in the exhaust gas of an engine (5), and a second case (63) for removing nitrogen oxides in the exhaust gas of the engine (5). In addition, the working vehicle is a structure equipped with a traveling machine body (2), on which the cab section (7) is installed, and a step frame (82) for supporting the cab section (7) on the traveling machine body (2), wherein a case-supporting base (121) is provided on the step frame (82), and the second case (63) is attached to the step frame (82) via the case-supporting base (121).

Description

Work vehicle

The present invention relates to a work vehicle such as an agricultural machine (tractor, combine) or a construction machine (bulldozer, hydraulic excavator, loader) equipped with an engine, and more specifically, particulate matter (soot, contained in exhaust gas). The present invention relates to a work vehicle such as a tractor provided with an exhaust gas purifying device for removing particulate oxide or nitrogen oxides (NOx) contained in the exhaust gas.

In a work vehicle such as a tractor or wheel loader, an opening / closing fulcrum shaft is arranged at the rear of the bonnet for covering the engine in order to improve the efficiency of maintenance work of the engine arranged at the front of the traveling machine body. The bonnet was rotated. Conventionally, a filter case having a diesel particulate filter and a catalyst case having a urea selective reduction catalyst are provided as exhaust gas purifiers (exhaust gas aftertreatment devices) in the exhaust path of a diesel engine. There has been known a technique for purifying exhaust gas discharged from a diesel engine by providing exhaust gas into a filter case and a catalyst case (see, for example, Patent Document 1 or 2).

JP 2009-74420 A US Patent Application Publication No. 2011/283687

When the catalyst case is assembled with being separated from the engine as in Patent Document 2, an exhaust pipe for supplying exhaust gas from the engine to the catalyst case is formed by a support member that supports the catalyst case on the traveling machine body. In the structure, there is a problem that the support member needs to be formed in a special structure, and the manufacturing cost cannot be easily reduced. Further, in the structure in which the traveling body is provided with a support member such as a catalyst case, the catalyst case can be supported at an arbitrary position of the traveling body, but there is a problem that the structure for mounting the catalyst case cannot be easily simplified.

Furthermore, in the structure in which the engine is supported on the traveling machine body by vibration isolation, when the exhaust pipe or the catalyst case is assembled on the traveling machine body side, the exhaust pipe or the catalyst case needs to be supported by vibration isolation. There is also a problem that the mounting structure cannot be easily simplified. Moreover, when the catalyst case is connected to the filter case via the urea mixing pipe and the urea water in the urea water tank is supplied to the urea mixing pipe, the fuel tank and the urea water tank are installed using the space below the operating unit. In this structure, the fuel tank and the urea water tank need to be arranged separately on the left and right sides of the traveling machine body, and the fuel tank inlet and the urea water tank inlet are on the left and right side parts of the traveling machine body. There is also a problem in handling such that the fuel tank is lubricated and the fuel tank or the urea water tank is troublesome. On the other hand, in a structure in which the fuel tank or urea water tank is arranged inside the hood that covers the engine, the capacity of the fuel tank or urea water tank is limited, the outer shape of the bonnet cannot be made compact, and the attached parts on the outer periphery of the engine There is also a problem that maintenance workability is lowered.

Therefore, the present invention seeks to provide a work vehicle that has been improved by examining these current conditions.

In order to achieve the above object, an invention according to claim 1 is directed to an operating unit on which an operator is boarded, a first case for removing particulate matter in exhaust gas from an engine, and a nitrogen oxide substance in exhaust gas from the engine. In a work vehicle including a second case to be removed, a structure including a traveling machine body that mounts the driving unit and a step frame that supports the driving unit on the traveling machine body, and a case support base is disposed on the step frame The second case is attached to the step frame via the case support.

According to a second aspect of the present invention, in the work vehicle according to the first aspect, the case support base protrudes forward from the step frame, and a case support on the rear side of the second case is provided on the front end side of the case support base. The rear end side of the bracket is detachably fastened, and the second case is attached to the front side of the step frame via the case support.

According to a third aspect of the present invention, in the work vehicle according to the first aspect, the case support base protrudes forward from the step frame, and the second case lower surface side is provided at an upper edge of the case support base front end side. The lower end side of the case support bracket is detachably fastened, and the second case is attached to the front side of the step frame via the case support base.

According to a fourth aspect of the present invention, in the work vehicle according to the first aspect, the case support base protrudes rearward from the step frame, and the case is mounted on the front end side of the case support bracket on the front side of the second case. The rear end side of the support base is detachably fastened, and the second case is attached between the step where the operator gets on and off the rear side of the step frame and the traveling machine body via the case support base. .

According to a fifth aspect of the present invention, in the work vehicle according to the first aspect of the present invention, the work vehicle includes a urea mixing pipe that connects the second case to the first case, and a urea water tank that supplies urea water to the urea mixing pipe. An anti-vibration support structure for the engine on the traveling machine body, wherein the exhaust pipe for adhering the first case and the urea mixing pipe to the upper position of the engine and the exhaust aircraft body for adhering to the traveling machine body side; The exhaust gas outlet side of the urea mixing pipe is connected by a flexible pipe.

According to a sixth aspect of the present invention, in the work vehicle according to the fifth aspect, the first case and the urea mixing pipe are disposed on the engine side, and the second case is disposed on the traveling machine body side, A flexible pipe is connected between the exhaust gas outlet of the urea mixing pipe and the exhaust gas inlet of the second case.

According to a seventh aspect of the invention, in the work vehicle according to the fifth aspect, a heat insulating cover body that covers the flexible pipe is provided, and the flexible pipe is disposed below a rear portion of a hood that covers the engine.

The invention according to claim 8 is the work vehicle according to claim 5, wherein the exhaust inlet side of the second case is connected to the exhaust outlet side of the first case via the urea mixing pipe. The first case is supported in a posture in which the engine output shaft core line and the exhaust gas movement direction of the first case are parallel, and the exhaust gas outlet side of the first case is directed toward one end of the engine output shaft. And extending the exhaust gas outlet side of the urea mixing pipe toward the other end side of the output shaft of the engine while supporting the urea mixing pipe in parallel with the exhaust gas moving direction of the first case. It is a thing.

The invention of claim 9 is the work vehicle according to claim 1, further comprising a urea mixing pipe connecting a second case to the first case, and a urea water tank for supplying urea water to the urea mixing pipe, The first case and the urea mixing pipe are arranged on the upper surface side of the engine, and the urea water tank is attached to the front of the traveling machine body in front of the engine via a tank support.

According to a tenth aspect of the present invention, in the work vehicle according to the ninth aspect, a water-cooling radiator is arranged on the upper surface side of the traveling machine body in front of the engine, and the tank support body is disposed below the radiator via a tank support. A urea water tank is attached, and a urea water injection pump of the urea water tank is connected to a urea water injection nozzle of the urea mixing pipe via a urea water injection pipe piped on the side surface of the radiator.

The invention according to claim 11 is the work vehicle according to claim 9, wherein a fuel tank is arranged below the driving part, and an oil filler port of the fuel tank is provided on the same side part of the traveling machine body. The urea water tank water injection port is disposed, the fuel tank oil injection port is installed behind the front wheel of the traveling machine body front part, and the urea water tank is disposed in front of the front wheel of the traveling machine body front part. A water inlet is installed.

According to a twelfth aspect of the present invention, in the work vehicle according to the ninth aspect, the front PTO shaft is provided in a front portion of the traveling machine body, and the concave portion in which the front PTO shaft can be freely fitted and inserted is provided in the urea water. The front PTO shaft is formed on either the upper surface or the bottom surface of the tank, and the front PTO shaft is inserted into the recess on the upper surface or the bottom surface of the urea water tank.

According to the first aspect of the present invention, the operating unit on which the operator gets on, the first case for removing particulate matter in the exhaust gas of the engine, and the second case for removing nitrogen oxides in the exhaust gas of the engine. In a work vehicle comprising: a traveling machine body that mounts the driving unit; and a step frame that supports the driving unit on the traveling machine body, wherein a case support is disposed on the step frame, and the step frame Since the second case is attached via the case support base, the case support base can be installed on the highly rigid step frame, and the manufacturing cost can be easily reduced by simplifying the size of the case support base. The support rigidity of the second case can be easily improved. Further, the second case support structure can be easily simplified as compared with a conventional structure that also supports the second case by using an exhaust pipe. In particular, in a tractor or the like in which the engine is disposed in the front part of the traveling machine body, the second case can be compactly installed on the lower side of the driving unit adjacent to the bonnet in which the engine is installed. The outer shape can be easily made compact, and the second case can be supported at a position deviated from the operator's driving field of view, thereby improving farm workability.

According to the second aspect of the present invention, the case support base is projected forward from the step frame, and the rear end side of the case support bracket on the back side of the second case can be attached to and detached from the front end side of the case support base. Since the second case is attached to the front side of the step frame via the case support base, the support structure of the second case can be simplified, and the open space on the front side of the operation unit can be simplified. The second case can be arranged, and the assembly workability of the second case can be easily improved.

According to the invention of claim 3, the case support base is projected forward from the step frame, and the lower end side of the case support bracket on the lower surface side of the second case is formed on the upper edge portion of the front end side of the case support base. Since the second case is fastened detachably and the second case is attached to the front side of the step frame via the case support, the second case is raised and lowered to the case support from above the case support. Thus, the second case can be easily temporarily fixed to the case support, and the workability of assembling the second case can be easily improved.

According to a fourth aspect of the present invention, the case support base protrudes backward from the step frame, and the rear end side of the case support base is attached to and detached from the front end side of the case support bracket on the front side of the second case. Since the second case is attached via the case support base between the step where the operator gets on and off and the traveling body among the rear side of the step frame, the second case is attached to the lower surface side of the step. The second case can be stored compactly, and the step can be utilized as a protective cover member on the upper surface side of the second case.

According to a fifth aspect of the present invention, a urea mixing pipe that connects the first case to the second case and a urea water tank that supplies urea water to the urea mixing pipe are provided, and the engine is isolated from vibration in the traveling machine body. An exhaust lead-out pipe body fixed to the traveling machine body side, and an exhaust gas outlet side of the urea mixture pipe, wherein the first case and the urea mixing pipe are fixed to the upper position of the engine. Are connected by a flexible pipe, so that the vibration of the engine can be absorbed by the flexible pipe. Therefore, the first case and the urea mixing pipe can be easily provided on the upper surface side of the engine. In addition to being able to be fixed, errors in the assembly dimensions of the urea mixing pipe or the exhaust lead-out pipe can be absorbed by the flexible pipe, so the urea mixing pipe and the exhaust lead-out pipe Connecting workability and can easily be improved. Further, the urea mixing pipe can be elongated on the outer peripheral side of the engine, and the mixing time of the exhaust gas and urea water required for the urea mixing pipe can be easily secured and the assembly workability of the urea mixing pipe can be secured. Etc. can be improved easily.

According to the invention of claim 6, the first case and the urea mixing pipe are disposed on the engine side, the second case is disposed on the traveling machine body side, and an exhaust gas outlet of the urea mixing pipe is disposed. Since the flexible pipe is connected between the exhaust gas inlets of the second case, the second case can be easily fixed to the traveling machine side, and the urea mixing pipe on the engine side and the traveling machine side An error in assembly dimensions with the second case (the exhaust lead-out pipe body) can be absorbed by the flexible pipe, and the connection workability between the urea mixing pipe and the second case can be easily improved. .

According to invention of Claim 7, while providing the heat insulation cover body which covers the said flexible pipe, and arrange | positioning the said flexible pipe under the rear part of the bonnet which covers the said engine, in the said flexible pipe in the said heat insulation cover body It is possible to easily suppress the temperature of the exhaust gas from decreasing, and to improve the attaching / detaching workability of the heat insulating cover body or the flexible pipe.

According to an eighth aspect of the present invention, the exhaust inlet side of the second case is connected to the exhaust outlet side of the first case via the urea mixing pipe, and the output shaft core line of the engine and the first The first case is supported in a posture in which the exhaust gas moving direction of one case is parallel, the exhaust gas outlet side of the first case is extended toward one end side of the output shaft of the engine, and the first case Since the urea mixing pipe is supported in parallel to the exhaust gas movement direction of the case, and the exhaust gas outlet side of the urea mixing pipe is extended toward the other end side of the output shaft of the engine, the engine Alternatively, the urea mixing tube is heated by the heat generation on the first case side, so that the crystallization of urea water in the urea mixing tube can be reduced, and the length necessary for mixing the urea water into the exhaust gas as ammonia. Or more To the at heating of the engine can be formed the length of the urea mixing tube heating unit warms longer, thereby improving the exhaust gas Kiyoshika function of removing nitrogen oxide materials in the exhaust gas in the second case.

According to the ninth aspect of the invention, a urea mixing pipe that connects the second case to the first case and a urea water tank that supplies urea water to the urea mixing pipe are provided, and the first case and the urea mixing pipe Is arranged on the upper surface side of the engine, and the urea water tank is attached to the front part of the traveling machine body in front of the engine via a tank support. The tank support can be installed in the tank, the manufacturing cost can be easily reduced by simplifying the size of the tank support, etc., the support rigidity of the urea water tank can be easily improved, and the urea water tank is assembled. Workability or urea water supply workability can be easily improved.

According to the invention of claim 10, a water cooling radiator is arranged on the upper side of the traveling machine body in front of the engine, and the urea water tank is attached to the front lower side of the radiator via a tank support, Since the urea water injection pump of the urea water tank is connected to the urea water injection nozzle of the urea mixing pipe via the urea water injection pipe piped on the side surface of the radiator, the urea mixing pipe and the urea water An intermediate portion of the urea water injection pipe extending between the tanks can be compactly piped on the side surface side of the radiator. The support for the urea water injection pipe can be simplified to easily reduce the manufacturing cost, the support rigidity of the urea water injection pipe can be easily improved, and the assembly workability of the urea water injection pipe is also easy. Can be improved.

According to invention of Claim 11, it is the structure which arrange | positions a fuel tank under the said operation part, Comprising: On the same side part of the said traveling body, the fuel inlet of the said fuel tank, and the water inlet of the said urea water tank The fuel tank oil filling port is installed behind the front wheel at the front of the traveling machine body, and the urea water tank filling port is installed in front of the front wheel at the front of the traveling machine body. From the above, it is possible to perform the fuel tank lubrication work and the urea water tank water fill work on the same side of the traveling machine body, respectively, so that the fuel tank lubrication workability or the urea water tank water fillability workability can be facilitated. In addition to being able to improve, the fuel tank oil injection port and the urea water tank water injection port are assigned to the rear and front of the front wheel, so that the operator can clearly identify the oil injection port and the water injection port. Or note The erroneous operation can be prevented.

According to the invention of claim 12, the front PTO shaft is provided at the front portion of the traveling machine body, and the recess into which the front PTO shaft can be loosely inserted is provided on either the upper surface or the bottom surface of the urea water tank. Since the front PTO shaft is inserted into the concave portion on the upper surface or the bottom surface of the urea water tank, it extends in the front-rear direction with almost no restriction on the front PTO shaft. The urea water tank can be arranged compactly in the front part of the traveling machine body by utilizing a dead space formed in an intermediate part of the front PTO shaft.

It is a perspective view of the tractor which shows 1st Embodiment. It is the same top view. It is a top view of an engine part. It is a right view of the same part. It is a left view of the same part. It is a right view of the 2nd case attachment structure. It is a right view of the 2nd case attachment structure which shows 2nd Embodiment. It is a right view of the 2nd case attachment structure which shows 3rd Embodiment. It is a right view which shows the modification which provided the front PTO axis | shaft. It is a right view which shows the modification which provided the front PTO axis | shaft.

Hereinafter, a first embodiment of the present invention will be described with reference to the drawings (FIGS. 1 to 6). First, a farm tractor 1 equipped with a diesel engine will be described with reference to FIGS. A farm tractor 1 as a work vehicle shown in FIGS. 1 and 2 is configured to perform a plowing work and the like for plowing a farm field by mounting a plow working machine (not shown). FIG. 1 is a perspective view of the tractor 1, and FIG. 2 is a plan view thereof. In the following description, the left side in the forward direction of the tractor 1 is simply referred to as the left side, and the right side in the forward direction is also simply referred to as the right side.

As shown in FIGS. 1 and 2, a farm tractor 1 as a work vehicle supports a traveling machine body 2 with a pair of left and right front wheels 3 and a pair of left and right rear wheels 4, and a diesel engine at the front of the traveling machine body 2. 5 and driving the rear wheel 4 and the front wheel 3 with the diesel engine 5, the vehicle is configured to travel forward and backward. The upper surface side and the left and right side surfaces of the diesel engine 5 are covered with an openable / closable bonnet 6.

In the upper surface of the traveling machine body 2, behind the bonnet 6, a driving cabin 7 is installed as a driving unit on which an operator gets on. Inside the cabin 7 is provided a front column 10 including a control seat 8 on which an operator sits, a control handle 9 as steering means, and the like. A fuel tank 12 that supplies fuel to the diesel engine 5 is provided below the boarding step 11 at the bottom of the cabin 7. In the front column 10, left and right brake pedals 13, a clutch pedal 14, a transmission pedal 15, a forward / reverse switching lever 16 and the like are disposed as steering devices.

The traveling machine body 2 also includes a mission case 17 for shifting the output from the diesel engine 5 and transmitting it to the rear wheels 4 (front wheels 3). The rear of the mission case 17 is connected to a tiller mechanism (not shown) and the like via a traction mechanism 21 such as a left and right lower link 18, a top link 19, and a left and right lift arm 20, and the like. The plowing machine and the like are driven by a PTO shaft (not shown) provided on the rear side surface of 17. Furthermore, the traveling machine body 2 of the tractor 1 includes a diesel engine 5, a transmission case 17, a clutch case 22 that connects them, a front chassis 23 that extends forward from the diesel engine 5, and the like. In addition, a pair of left and right boarding steps 24 for the operator to get on and off are arranged on the left and right outer portions of the cabin 7.

Next, the diesel engine 5 will be described with reference to FIGS. As shown in FIGS. 3 to 5, an intake manifold 33 is disposed on one side surface of the cylinder head 32 of the diesel engine 5. The cylinder head 32 is mounted on a cylinder block 35 in which an engine output shaft (crank shaft) and a piston (not shown) are incorporated. An exhaust manifold 36 is disposed on the other side of the cylinder head 32, and the front end and the rear end of the engine output shaft are projected from the front and rear surfaces of the cylinder block 35.

3 to 5, a flywheel housing 38 is fixed to the rear surface of the cylinder block 35. A flywheel (not shown) is provided in the flywheel housing 38. The front side of the clutch case 22 is connected to the rear side of the flywheel housing 38. The power of the diesel engine 5 is extracted from the rear end side of the engine output shaft on which the flywheel is pivoted toward the transmission case 17. Further, an oil pan 39 is disposed on the lower surface of the cylinder block 35, a cooling fan 40 is disposed on the front surface side of the cylinder block 35, and a radiator 41 is installed facing the cooling fan 40. An oil cooler 42, an air cleaner 43, a battery 44, and the like are disposed on the front chassis 23 in front of the radiator 41.

As shown in FIGS. 3 to 5, the intake manifold 33 is provided with an exhaust gas recirculation device (EGR) 45 for taking in exhaust gas for recirculation. An air cleaner 43 shown in FIG. 4 is connected to the intake manifold 33. The external air that has been dedusted and purified by the air cleaner 43 is sent to the intake manifold 33 and supplied to each cylinder of the diesel engine 5.

With the above configuration, a part of the exhaust gas discharged from the diesel engine 5 to the exhaust manifold 36 is recirculated from the intake manifold 33 to each cylinder of the diesel engine 5 via the exhaust gas recirculation device 45. The combustion temperature of the diesel engine 5 is lowered, the amount of nitrogen oxide (NOx) discharged from the diesel engine 5 is reduced, and the fuel efficiency of the diesel engine 5 is improved.

A cooling water pump 46 for circulating cooling water in the cylinder block 35 and the radiator 41 is provided. A cooling water pump 46 is arranged on the cooling fan 40 installation side on the front side of the diesel engine 5. The cooling water pump 46 and the cooling fan 40 are connected to the engine output shaft of the diesel engine 5 via a V belt or the like, and the cooling water pump 46 and the cooling fan 40 are driven. While the cooling water is fed from the cooling water pump 46 into the cylinder block 35 via the EGR cooler 47 of the exhaust gas recirculation device 45, the diesel engine 5 is cooled by the cooling fan 40 wind. .

As shown in FIG. 4, each of the four cylinders 51 of the diesel engine 5 includes a fuel pump 52 and a common rail 53 that connect the fuel tank 12 shown in FIG. A common rail 53 and a fuel filter 54 are arranged on the intake manifold 33 installation side of the cylinder head 32, and a fuel pump 52 is arranged in the cylinder block 35 below the intake manifold 33. Each injector 51 has an electromagnetic switching control type fuel injection valve (not shown).

While the fuel in the fuel tank 12 is sucked into the fuel pump 52 via the fuel filter 54, the common rail 53 is connected to the discharge side of the fuel pump 52, and the cylindrical common rail 53 is connected to each injector 51 of the diesel engine 5. It is connected. The surplus of the fuel pumped from the fuel pump 52 to the common rail 53 is returned to the fuel tank 12, high-pressure fuel is temporarily stored in the common rail 53, and the high-pressure fuel in the common rail 53 is used for each diesel engine 5. Supplied inside the cylinder.

With the above configuration, the fuel in the fuel tank 12 is pumped to the common rail 53 by the fuel pump 52, the high-pressure fuel is stored in the common rail 53, and the fuel injection valves of the injectors 51 are controlled to open and close. High-pressure fuel in the common rail 53 is injected into each cylinder of the diesel engine 5. That is, by electronically controlling the fuel injection valve of each injector 51, the fuel injection pressure, injection timing, and injection period (injection amount) can be controlled with high accuracy. Therefore, nitrogen oxides (NOx) discharged from the diesel engine 5 can be reduced.

As shown in FIGS. 3 to 6, as an exhaust gas purification device 61 for purifying exhaust gas discharged from each cylinder of the diesel engine 5, diesel particulates that remove particulate matter in the exhaust gas of the diesel engine 5 are used. A first case 62 as a curate filter (DPF) and a second case 63 as a urea selective catalytic reduction (SCR) system for removing nitrogen oxides in exhaust gas of the diesel engine 1 are provided. As shown in FIG. 3, an oxidation catalyst 64 and a soot filter 65 are provided in the first case 62. The second case 63 includes an SCR catalyst 66 and an oxidation catalyst 67 for reducing urea selective catalyst.

Exhaust gas discharged from each cylinder of the diesel engine 5 to the exhaust manifold 36 is discharged to the outside via the exhaust gas purification device 61 and the like. The exhaust gas purification device 61 is configured to reduce carbon monoxide (CO), hydrocarbons (HC), particulate matter (PM), and nitrogen oxides (NOx) in the exhaust gas of the diesel engine 5. is doing.

The first case 62 is configured in a horizontally long and long cylindrical shape extending long in a direction parallel to the output shaft (crankshaft) of the diesel engine 5 in a plan view. A DPF inlet pipe 68 for taking in exhaust gas is provided on one end of the first case 62 in the cylindrical shape. Of the front and rear surfaces of the diesel engine 5, the one end side and the other end side of the first case 62 in the exhaust gas movement direction can be attached to and detached from the front and rear surfaces of the cylinder head 32 via the front support leg body 69 and the rear support leg body 70. I support it. That is, the first case 62 is attached to the upper surface side of the diesel engine 5 through the front support leg 69 and the rear support leg 70. The first case 62 is supported in parallel with the exhaust manifold 36 with the longitudinal direction of the cylindrical first case 62 facing the longitudinal direction of the diesel engine 5.

Further, a supercharger 71 for forcibly sending air to the diesel engine 5 is disposed at the exhaust gas outlet of the exhaust manifold 36. The DPF inlet pipe 68 is communicated with the exhaust manifold 36 via the supercharger 71, and the exhaust gas of the diesel engine 5 is introduced into the first case 62 from the DPF inlet pipe 68. On the other hand, a DPF outlet pipe 72 for exhaust gas exhaust is provided on the other end side of the cylindrical shape of the first case 62. The DPF outlet pipe 72 of the first case 62 is connected to the inlet side of the urea mixing pipe 73, and the exhaust gas of the first case 28 is introduced into the urea mixing pipe 73.

On the other hand, the second case 63 is configured in a horizontally long long cylindrical shape extending long in the left-right direction. An SCR inlet pipe 74 for taking in exhaust gas is provided at the left end of the cylindrical shape of the second case 63. An SCR inlet pipe 74 is connected to the outlet side of the urea mixing pipe 73 through a bellows-like connecting pipe 75 that can be bent and stretched. Furthermore, the end of the urea mixing pipe 73 to which the bellows-like connecting pipe 75 is connected is detachably fixed to the side surface of the cylinder block 35 with a pipe bracket 76.

Further, the DPF inlet pipe 68 is located on the rear side of the diesel engine 5, the exhaust gas flows from the rear part to the front part of the first case 62, and the urea mixing pipe provided in parallel with the first case 62 at the upper part of the diesel engine 5. The exhaust gas moves to 73. That is, the urea mixing pipe 73 extending in the front-rear direction is fixed to the upper surface side of the diesel engine 5 via the first case 62 and the pipe bracket 76, and the first case 62 side of the upper surface of the diesel engine 5 is fixed. On the other hand, the urea mixing pipe 73 is arranged in parallel with the first case 62, and the first case 62 and the urea mixing pipe 73 can be integrally fixed to the diesel engine 5 supported by vibration isolation. The mechanical vibration on the urea mixing pipe 73 side is blocked by the bellows-like connecting pipe 75 and is not transmitted to the SCR inlet pipe 74 side.

Also, as shown in FIG. 6, the lower end side of the tail pipe 81 is connected to the right end of the cylindrical shape of the second case 63. The tail pipe 81 is erected substantially vertically along the cabin frame 82 at the right corner of the operation cabin 7. The tail pipe 81 and the pipe cover 84 are fixed to the cabin frame 82 via the pipe mounting bracket 83. On the other hand, the base end side of the left and right step frame 86 as a traveling machine frame is bolted to the left and right side surfaces of the clutch case 22 via the board bracket 85, and the left and right step frames are directed toward the left and right outer sides of the clutch case 22. The front end side of 86 is horizontally extended, and the operation cabin 7 is attached to the upper surface side of the middle part of the left and right step frames 86 via the cabin fixing shaft body 87, and the getting-on / off step 24 is attached to the front end parts of the left and right step frames 86 .

Further, as shown in FIG. 6, the step frame 86 supports the second case 63, a column member 120 is welded and fixed to the lower surface side of the step frame 86, and a pair of left and right cases are mounted on the front side of the column member 120. The support plate 121 is fixed by welding, the case support plate 121 is integrally fixed to the step frame 86, and a pair of left and right case support plates 121 are projected from the support member 120 toward the front. A case support bracket 122 is integrally welded and fixed to the back side of the second case 63 out of the outer peripheral surface of the second case 63 for purifying exhaust gas, and the case support bracket 122 is moved rearward from the second case 63. Make it project. The case support bracket 122 is fitted between the pair of left and right case support plate bodies 121, and the upper bolt 126a and the lower bolt 126b are screwed to the left and right side surfaces of the pair of left and right case support plate bodies 121 and the case support bracket 122 from the left and right directions. The case support bracket 122 is fastened to the case support plate 121, and the second case 63 is detachably fixed to the step frame 86.

Further, the upper bolt 126a is removably locked to the engagement notch 121a having a forward opening shape of the case support plate 121, and the lower bolt 126b is passed through the position adjusting long hole 121b of the case support plate 121. That is, when the second case 63 is assembled, first, the upper bolt 126a is temporarily fixed to the case support bracket 122, the second case 63 is brought close to the mounting position of the case support plate 121, and the case support plate 121 is attached. The upper bolt 126a is engaged with the engagement notch 121a, and the second case 63 is temporarily fixedly supported by the case support plate 121. Thereafter, the lower bolt 126b is passed through the position adjusting long hole 121b of the case support plate 121, the lower bolt 126b is fastened to the case support bracket 122, and the upper bolt 126a is also fastened to the case support bracket 122. 126b, the case support bracket 122 is detachably fixed to the case support plate 121, and the second case 63 is mounted on the front side of the driving cabin 7 (driving unit) via the step frame 86. Yes. Accordingly, the first case 28 is arranged on the upper surface side of the diesel engine 5 in a horizontally long posture facing in the front-rear direction, while the second case 63 is placed in a horizontally long posture facing in the left-right direction on the right side of the rear portion of the diesel engine 5. Is placed.

Further, as shown in FIGS. 4 and 5, a urea water tank 91 is mounted on the traveling machine body 2 (front chassis 23) at the front of the bonnet 6. An oil injection port 92 for the fuel tank 12 is provided in the lower front portion on the left side of the cabin 7, and a water injection port 93 for the urea water tank 91 is provided on the left side of the front portion of the bonnet 6. An oil injection port 92 and a water injection port 93 are arranged on the left side of the traveling machine body 2 where the frequency of getting on and off by the operator is high, and a urea water tank 91 is arranged between the left and right front chassis 23 via a tank support frame 90. On the upper surface side of the front chassis 23, the oil cooler 42, the air cleaner 43, and the battery 44 are respectively disposed above the urea water tank 91 (in the engine room 89 formed by the bonnet 6).

In addition, a radiator 41 is disposed between the cooling fan 40 and the oil cooler 42 on the front surface side of the diesel engine 5 in the upper surface side of the front chassis 23, and the diesel engine in the engine room 89 formed by the bonnet 6. 5. A urea mixing pipe 73 is extended and supported in the front-rear direction on the upper surface side (the right side of the second case where the exhaust gas moves from the rear to the front).

Further, a urea water injection pump 94 that pumps the urea aqueous solution in the urea water tank 91, an electric motor 95 that drives the urea water injection pump 94, and urea that is connected to the urea water injection pump 94 via a urea water injection pipe 96. A water injection nozzle 97 is provided. A urea water injection pump 94 and an electric motor 95 are provided on the rear surface side of the urea water tank 91, the middle of the urea water injection pipe 96 is covered with a heat insulating pipe cover body 96 a, the right side surface of the shroud 47, and the radiator 41. A pipe cover body 96 a is fixedly supported on the right side of the radiator 41 via a pipe stopper 48, and a urea water injection pipe 96 is piped from the right side surface of the radiator 41 toward the urea mixing pipe 73. The shroud 47 is disposed on the rear surface side of the radiator 41, covers the outside of the cooling fan 40 with the shroud 47, and moves the cooling fan 40 wind from the radiator 41 toward the outer periphery of the diesel engine 5.

Further, the urea water injection nozzle 97 is attached to the front end portion of the urea mixing pipe 73 connected to the front surface side of the first case 62 via the injection base 98. One end side of the urea water injection pipe 96 is connected to the urea water injection pump 94, the other end side of the urea water injection pipe 96 is connected to the urea water injection nozzle 97, and the urea water injection nozzle 97 is connected to the inside of the urea mixing pipe 73. The urea aqueous solution in the urea water tank 91 is sprayed. The urea water supplied into the urea mixing pipe 73 is configured to be mixed as ammonia in the exhaust gas from the first case 62 to the second case 63.

In addition, as shown in FIGS. 3 and 6, a heat insulating cover body 99 (or a heat-resistant heat insulating material such as glass fiber) covering the bellows-like connecting pipe 75 is provided, and a heat insulating cover is provided on the outer peripheral side of the bellows-like connecting pipe 75. The body 99 is wound, and the heat insulating cover body 99 prevents the exhaust gas temperature in the bellows-like connecting pipe 75 from decreasing, and the crystallization of urea in the exhaust gas in the bellows-like connecting pipe 75 is suppressed. Yes. The urea mixing pipe 73 has an elbow pipe part that changes the movement direction of the exhaust gas by about 90 degrees and a long cylindrical straight pipe part that is connected to the SCR inlet pipe 74. An injection pedestal 98 is fixed by welding to an elbow pipe part near the elbow pipe part and the straight pipe part, and a urea aqueous solution is supplied from the urea water injection nozzle 97 toward the inner hole of the straight pipe part from the elbow pipe part side. It sprays and ammonia is produced | generated by hydrolysis of the urea aqueous solution, and the ammonia is mixed in the exhaust gas in the straight pipe part.

With the above configuration, the oxidation catalyst 64 and the soot filter 65 in the first case 62 reduce carbon monoxide (CO) and hydrocarbons (HC) in the exhaust gas of the diesel engine 5. Next, urea water from the urea water injection nozzle 97 is mixed into the exhaust gas from the diesel engine 5 inside the urea mixing pipe 73. The SCR catalyst 66 and the oxidation catalyst 67 in the second case 63 reduce nitrogen oxides (NOx) in the exhaust gas in which urea water is mixed as ammonia. That is, exhaust gas with reduced carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx) is discharged from the tail pipe 81 to the outside of the machine.

As shown in FIGS. 1 to 6, a traveling machine body 2 on which a diesel engine 5 is mounted, a first case 62 for removing particulate matter in the exhaust gas of the engine 5, and a nitrogen oxide substance in the exhaust gas of the diesel engine 5 In the work vehicle including the second case 63 for removing the vehicle, the step frame 86 on the lower surface side of the driving cabin 7 on one side of the traveling vehicle body 2 among the lower surface side of the driving cabin 7 as the driving portion installed in the traveling vehicle body 2. A case support plate 121 and a case support bracket 122 as a case support are arranged on the lower side of the driving cabin 7, and the second case 63 is mounted in a horizontally long posture via the case support plate 121 and the case support bracket 122. Yes. Therefore, the case support plate 121 can be installed on the highly rigid step frame 86, and the manufacturing cost can be easily reduced by simplifying the size of the case support plate 121 and the case support bracket 122, and the second case 63 can be supported. The rigidity and the like can be easily improved, and the assembly workability of the second case 63 can be easily improved.

As shown in FIGS. 3 to 6, a second case 63 having a horizontally long posture is attached along the front end side of the boarding step 11 on the lower surface side of the operation cabin 7 via the case support plate 121 and the case support bracket 122. Yes. Therefore, the second case 63 can be compactly installed while ensuring the front view of the operator of the driving cabin 7. Further, the second case 63 support structure can be easily simplified as compared with a conventional structure that also supports the second case 63 using the exhaust pipe.

As shown in FIGS. 3 to 5, a urea water tank 91 for purifying exhaust gas and a urea mixing pipe 73 for supplying urea water from the urea water tank 91 are provided, and the urea mixing pipe 73 is provided at the exhaust outlet of the first case 62. The exhaust gas inlet of the second case 63 is connected to the upper surface of the diesel engine 5 so that the first case 62 is supported, and the urea mixing pipe is parallel to the exhaust gas movement direction of the first case 62. 73 is extended. Accordingly, the long urea mixing pipe 73 necessary for mixing urea water can be compactly arranged on the upper surface of the diesel engine 5, and the urea mixing pipe 73 is heated by the heat generated on the diesel engine 5 side. Even in this operation, the temperature of the exhaust gas or urea aqueous solution in the urea mixing pipe 73 can be easily maintained, and the crystallization of urea water in the urea mixing pipe 73 can be reduced.

As shown in FIGS. 3 to 5, the front chassis 23 as the left and right engine frames is extended from the diesel engine 5 forward, and the radiator 41 or the front wheels 3 are arranged on the left and right front chassis 23. A urea water tank 91 is attached between the left and right front chassis 23. Therefore, the urea water tank 91 can be easily assembled using the space between the left and right front chassis 23, and the urea water tank 91 can be made compact inside the hood 6 (engine room 89) for covering the diesel engine 5. Can be placed.

As shown in FIGS. 1 to 4 and 6, the traveling machine body 2 on which the diesel engine 5 is mounted, the first case 62 for removing particulate matter in the exhaust gas of the diesel engine 5, and the exhaust gas of the diesel engine 5 In a work vehicle comprising a second case 63 for removing nitrogen oxides, a urea mixing pipe 73 connecting the second case 63 to the first case 62, and a urea water tank 91 for supplying urea water to the urea mixing pipe 73 The diesel engine 5 is vibration-proofed and supported on the traveling machine body 2, and the first case 62 and the urea mixing pipe 73 are fixed to the upper position of the diesel engine 5 and the exhaust lead-out pipe is fixed to the traveling machine body 2 side. The SCR inlet pipe 74 as a body and the exhaust gas outlet side of the urea mixing pipe 73 are connected by a bellows-like connecting pipe 75 as a flexible pipe. Since the vibration of the diesel engine 5 can be absorbed by the flexible pipe 75, the first case 62 and the urea mixing pipe 73 can be easily fixed to the upper surface side of the diesel engine 5, and the urea mixing pipe 73 or the SCR inlet pipe Since errors in assembly dimensions such as 74 can be absorbed by the bellows-like connecting pipe 75, the connection workability of the urea mixing pipe 73 and the SCR inlet pipe 74 can be easily improved. Further, the urea mixing pipe 73 can be extended to the outer periphery side of the diesel engine 5 so that the mixing time of the exhaust gas and urea water necessary for the urea mixing pipe 73 can be easily secured and the urea mixing pipe 73 is assembled. Workability can be easily improved.

As shown in FIGS. 3, 4, and 6, the first case 62 and the urea mixing pipe 73 are disposed on the diesel engine 5 side, and the second case 63 is disposed on the traveling machine body 2 side. Since the bellows-like connecting pipe 75 is connected between the exhaust gas outlet and the exhaust gas inlet of the second case 63, the second case 63 can be easily fixed to the traveling machine body 2 side, and urea on the diesel engine 5 side can be secured. The assembly size error between the mixing pipe 73 and the second case 63 (SCR inlet pipe 74) on the traveling machine body 2 side can be absorbed by the bellows-like connecting pipe 75, and the urea mixing pipe 73 and the second case 63 are absorbed. It is possible to easily improve the connection workability.

As shown in FIGS. 3, 4, and 6, a heat insulating cover body 99 that covers the bellows-like connecting pipe 75 is provided, and the bellows-like connecting pipe 75 is arranged below the rear part of the bonnet 6 that covers the diesel engine 5. In addition, it is possible to easily suppress the temperature of the exhaust gas in the bellows-like connecting pipe 75 from being lowered by the heat insulating cover body 99, and to improve the attaching / detaching workability of the heat insulating cover 99 or the bellows-like connecting pipe 75.

As shown in FIGS. 3 to 6, a urea water tank 91 for purifying exhaust gas and a urea mixing pipe 73 for supplying urea water from the urea water tank 91 are provided, and the urea mixture 73 is provided on the exhaust outlet side of the first case 62. The first case 62 is supported in a posture in which the output shaft core line of the diesel engine 5 and the exhaust gas movement direction of the first case 62 are parallel to each other. The exhaust gas outlet side of the first case 62 is extended toward one end side of the output shaft of the engine 5 (the front part of the diesel engine 5 in which the cooling fan 40 is disposed) and parallel to the exhaust gas movement direction of the first case 62. The urea mixing pipe 73 is supported on the other end of the diesel engine 5 toward the other end of the output shaft of the diesel engine 5 (the rear part of the diesel engine 5 in which the flywheel housing 38 is disposed). Since the gas outlet side is extended, the urea mixing pipe 73 is heated by the heat generated on the diesel engine 5 or the first case 62 side, and the crystallization of urea water in the urea mixing pipe 73 can be reduced. At the same time, the heating part of the urea mixing pipe 73 (elbow pipe part and straight pipe part) heated by the heat generated by the diesel engine 5 to a length necessary for mixing the urea water as ammonia into the exhaust gas or longer. ) Can be formed long, and the exhaust gas hatching function for removing nitrogen oxides in the exhaust gas in the second case 63 can be improved.

As shown in FIGS. 1 to 5, an operation cabin 7 serving as an operation unit on which an operator is boarded, a first case 62 for removing particulate matter in the exhaust gas of the diesel engine 5, and the exhaust gas of the diesel engine 5 in the exhaust gas In a work vehicle including a second case 63 for removing nitrogen oxides, a urea mixing pipe 73 for connecting the second case 63 to the first case 62, and a urea water tank 91 for supplying urea water to the

urea mixing pipe

73, 1 is a structure in which a case 62 and a urea mixing pipe 73 are arranged on the upper surface side of the diesel engine 5, and a tank support frame 90 as a tank support is provided at the front of the traveling machine body 2 (front chassis 23) in front of the diesel engine 5. A urea water tank 91 is attached via Therefore, the tank support frame 90 can be installed in the front part (front chassis 23) of the highly rigid traveling machine body 2, and the manufacturing cost can be easily reduced by simplifying the size of the tank support frame 90, and the urea water tank 91 can be supported. The rigidity and the like can be easily improved, and the assembly workability or urea water supply workability of the urea water tank 91 can be easily improved.

As shown in FIG. 4, a water cooling radiator 41 is arranged on the upper side of the traveling machine body in front of the diesel engine 5, and a urea water tank 91 is attached to the front lower side of the radiator 41 via a tank support frame 90, and the radiator The urea water injection pump 94 of the urea water tank 91 is connected to the urea water injection nozzle 97 of the urea mixing pipe 73 through the urea water injection pipe 96 piped on the side surface of 41. Therefore, the middle part of the urea water injection pipe 96 extending between the urea mixing pipe 73 and the urea water tank 91 can be compactly piped on the side surface side of the radiator 41. The support for the urea water injection pipe 96 (pipe stopper 48) can be simplified to easily reduce the manufacturing cost, and the support rigidity of the urea water injection pipe 96 can be easily improved, and the urea water injection pipe 96 is assembled. Workability can be easily improved.

As shown in FIG. 5, the fuel tank 12 is arranged below the operation cabin 7, and the fuel injection port 92 of the fuel tank 12 and the water injection port 93 of the urea water tank 91 are provided on the same side portion of the traveling machine body 2. The fuel inlet 12 of the fuel tank 12 is installed behind the front wheel 3 at the front of the traveling machine body 2, and the water inlet 93 of the urea water tank 91 is installed in front of the front wheel 3 at the front of the traveling machine body 2. It is installed. Therefore, the fuel tank 12 and the urea water tank 91 can be lubricated on the same side of the traveling machine body 2, respectively, and the fuel tank 12 or the urea water tank 91 can be easily lubricated. It is possible to improve, and since the oil injection port 92 of the fuel tank 12 and the water injection port 93 of the urea water tank 91 are distributed to the rear and front of the front wheel 3, the operator clearly defines the oil injection port 92 and the water injection port 93. It is possible to identify and prevent erroneous operation of oiling or water injection.

Further, as shown in FIG. 6, a case support plate 121 (case support base) is projected forward from the cabin frame 82 (step frame), and on the front end side of the case support plate 121, on the back side of the second case 63. The rear end side of the case support bracket 122 is detachably fastened, and the second case 63 is attached to the front side of the cabin frame 82 via the case support plate 121. Accordingly, the support structure of the second case 63 can be simplified, the second case 63 can be disposed in the open space in front of the driving cabin 7 (driving unit), and the assembling workability of the second case 63 can be easily improved. .

Next, with reference to FIG. 7, a mounting structure of the second case 63 showing the second embodiment will be described. As shown in FIG. 7, the second frame 63 is supported by the step frame 86, a column member 120 is welded and fixed to the front side of the step frame 86, and a pair of left and right case support plates is mounted on the front side of the column member 120. The body 121 is fixed by welding, the case support plate 121 is integrally fixed to the step frame 86, and a pair of left and right case support plates 121 are projected from the support member 120 toward the front. A case support bracket 122 is integrally welded and fixed to the lower surface side of the second case 63 in the outer peripheral surface of the second case 63 for purifying exhaust gas, and the case support bracket 122 is directed downward from the second case 63. Make it project. The case support bracket 122 is fitted between the pair of left and right case support plate bodies 121, and the upper bolt 126a and the lower bolt 126b are screwed to the left and right side surfaces of the pair of left and right case support plate bodies 121 and the case support bracket 122 from the left and right directions. The case support bracket 122 is fastened to the case support plate 121, and the second case 63 is detachably fixed to the step frame 86.

Further, the upper bolt 126a is detachably locked to the engagement notch 121a having the upward opening shape of the case support plate 121, and the lower bolt 126b is passed through the position adjusting long hole 121b of the case support plate 121. That is, when assembling the second case 63, as in the first embodiment, the case support bracket 122 is detachably fixed to the case support plate 121 via the

bolts

126a and 126b, and the step frame 86 is used. The second case 63 is mounted on the front side of the driving cabin 7 (driving unit). Therefore, the second case 63 can be supported at a higher position than in the first embodiment.

In addition, as shown in FIG. 7, a case support plate 121 (case support) protrudes forward from the cabin frame 82 (step frame), and an upper edge portion on the front end side of the case support plate 121 (case support). The lower end side of the case support bracket 122 on the lower surface side of the second case 63 is detachably fastened, and the second case 63 is attached to the front side of the cabin frame 82 via the case support plate 121. Accordingly, the second case 63 can be attached to and detached from the case support plate 121 by moving the second case 63 up and down from the case support plate 121, and the second case 63 can be easily temporarily fixed to the case support plate 121. Assembling workability can be easily improved.

Next, with reference to FIG. 8, a mounting structure of the second case 63 showing the third embodiment will be described. As shown in FIG. 8, the second case 63 is supported by the step frame 86, a support member 120 is welded and fixed to the front side of the step frame 86, and a pair of left and right case support plates is provided on the rear surface side of the support member 120. The body 121 is fixed by welding, the case support plate 121 is integrally fixed to the step frame 86, and a pair of left and right case support plates 121 are projected from the support member 120 toward the rear. A case support bracket 122 is integrally welded and fixed to the front surface side of the second case 63 out of the outer peripheral surface of the second case 63 for purifying exhaust gas, and the case support bracket 122 is moved forward from the second case 63. Make it project. The case support bracket 122 is fitted between the pair of left and right case support plate bodies 121, and the upper bolt 126a and the lower bolt 126b are screwed to the left and right side surfaces of the pair of left and right case support plate bodies 121 and the case support bracket 122 from the left and right directions. The case support bracket 122 is fastened to the case support plate 121, and the second case 63 is detachably fixed to the step frame 86.

Further, the upper bolt 126a is detachably locked to the engagement notch 121a having a rearward opening shape of the case support plate 121, and the lower bolt 126b is passed through the position adjusting long hole 121b of the case support plate 121. That is, when assembling the second case 63, the case support bracket 122 is detachably fixed to the case support plate 121 via the

bolts

126a and 126b, and the lower surface side of the step frame 86, as in the first embodiment. The second case 63 is attached to the. Therefore, the second case 63 can be supported between the right side surface of the clutch case 22 and the inner surface side of the right getting on / off step 24. In the third embodiment, the second case 63 is supported in a horizontally long posture so that the exhaust gas movement direction of the second case 63 is left and right, but the exhaust gas movement direction of the second case 63 is It is also possible to support the second case 63 in a posture that is horizontally long in the front-rear direction so that the second case 63 and the tail pipe 81 extend rearward on the lower surface side of the boarding step 11.

As shown in FIG. 8, the lower side of the driving cabin 7 is below the boarding step 11 and between the one side surface of the traveling machine body 2 and the boarding / exiting step 24 via the case support plate 121 and the case support bracket 122. Two cases 63 are attached. Accordingly, the outside of the second case 63 can be protected at the getting-on / off step 24, and the space between the side surface of the traveling machine body 2 and the getting-on / off step 24 can be utilized to install the second case 63 in a compact manner.

As shown in FIGS. 1 and 6 to 8, an operation cabin 7 as an operation unit on which an operator is boarded, a first case 62 for removing particulate matter in the exhaust gas of the diesel engine 5, and exhaust gas of the diesel engine 5. A work vehicle including a second case 63 that removes nitrogen oxides in the gas includes a traveling machine body 2 on which the driving cabin 7 is installed, and a cabin frame 82 as a step frame that supports the driving cabin 7 on the traveling machine body 2. In the structure, a case support plate 121 as a case support is disposed on the step frame 82, and the second case 63 is attached to the cabin frame 82 via the case support plate 121. Therefore, the case support plate 121 can be installed on the highly rigid cabin frame 82, and the manufacturing cost can be easily reduced by simplifying the case support plate 121, and the support rigidity of the second case 63 can be easily reduced. Can be improved. Further, the second case 63 support structure can be easily simplified as compared with a conventional structure that also supports the second case 63 using the exhaust pipe. In particular, in a tractor or the like in which the diesel engine 5 is disposed in the front part of the traveling machine body 2, the second case 63 can be compactly installed on the lower side of the operation cabin 7 adjacent to the bonnet 6 in which the diesel engine 5 is installed. The outer shape such as 6 can be easily made compact, and the second case 63 can be supported at a position deviated from the operator's driving field of view.

As shown in FIG. 8, the case support plate 121 protrudes rearward from the cabin frame 82, and the rear end side of the case support plate 121 is attached to and detached from the front end side of the case support bracket 122 on the front side of the second case 63. The second case 63 is attached via a case support plate 121 between the boarding step 11 where the operator gets on and off and the traveling machine body 2 on the rear side of the cabin frame 82. Therefore, the second case 63 can be stored compactly on the lower surface side of the boarding step 11, and the boarding step 11 can be used as a protective cover member on the upper surface side of the second case 63.

Next, a structure provided with a front PTO shaft will be described with reference to FIG. As shown in FIG. 9, a front PTO case 26 is fixed to the front end portion of the front chassis 23 (the traveling vehicle body 2), and a front PTO shaft 27 is pivotally supported on the lower front side of the front PTO case 26. A front PTO shaft 27 projects toward the front, and a front transmission shaft 28 extends from the rear upper part of the front PTO case 26 toward the rear to drive the cooling fan 40 and the like. 29, the power of the diesel engine 5 is transmitted to the rear end side of the front transmission shaft 28, and the power of the engine 5 of the front transmission shaft 28 is transmitted via a front PTO case 26 incorporating a transmission gear or a PTO clutch (not shown). Is transmitted to the front PTO shaft 27, and the front PTO shaft 27 is driven by engine 5 power. It is configured so as. Further, an upward concave portion 30 having an upward opening shape into which the front PTO shaft 27 can be loosely inserted is formed on the upper surface side of the urea water tank 91 disposed between the left and right front chassis 23 via the tank support frame 90, and urea is formed. An intermediate portion of the front PTO shaft 27 that extends substantially horizontally in the front-rear direction is inserted into the upward recess 30 on the upper surface of the water tank 91.

Next, a modified example of the structure provided with the front PTO shaft 27 will be described with reference to FIG. As shown in FIG. 10, the front PTO shaft 27 is provided in the same manner as in FIG. 9, and the front PTO shaft 27 is disposed on the lower surface side of the urea water tank 91 disposed between the left and right front chassis 23 via the tank support frame 90. A downward recessed portion 31 having an open downward shape that can be freely inserted is formed, and an intermediate portion of the front PTO shaft 27 that extends substantially horizontally in the front-rear direction is inserted into the downward recessed portion 31 on the lower surface of the urea water tank 91. It is composed.

As shown in FIG. 9 or FIG. 10, the front PTO shaft 27 is provided in the front portion of the front chassis 23 (the traveling machine body 2), and an upward recess 30 or a downward recess 31 into which the front PTO shaft 27 can be freely inserted is inserted. The front PTO shaft 27 is formed on either the upper surface or the bottom surface of the urea water tank 91, and the front PTO shaft 27 is fitted into the upward concave portion 30 or the downward concave portion 31 of the upper surface or the bottom surface of the urea water tank 91. Therefore, the dead space formed in the middle part of the front PTO shaft 27 extending in the front-rear direction is hardly restricted by the front PTO shaft 27, and is used at the front portion of the front chassis 23 (the traveling machine body 2). The urea water tank 91 can be arranged in a compact manner.

2 Driving body 5 Diesel engine 7 Driving cabin (operating part)
11 Boarding Step 62 First Case 63 Second Case 82 Cabin Frame (Step Frame)
121 Case support plate (case support)
122 Case support bracket

Claims

In a work vehicle comprising an operating unit on which an operator is boarded, a first case for removing particulate matter in engine exhaust gas, and a second case for removing nitrogen oxide substance in engine exhaust gas,
A traveling machine body in which the driving unit is installed, and a step frame that supports the driving unit on the traveling machine body, wherein a case support is disposed on the step frame, and the case support is mounted on the step frame. A work vehicle having the second case attached thereto.
The case support is protruded forward from the step frame, and the rear end side of the case support bracket on the back side of the second case is detachably fastened to the front end of the case support, and the front side of the step frame The work vehicle according to claim 1, wherein the second case is attached to the vehicle via the case support.
The case support is projected forward from the step frame, the lower end of the case support bracket on the lower surface of the second case is detachably fastened to the upper edge of the front end of the case support, and the step frame The work vehicle according to claim 1, wherein the second case is attached to the front side of the vehicle via the case support.
The case support is protruded rearward from the step frame, and the rear end side of the case support is detachably fastened to the front end side of the case support bracket on the front side of the second case. The work vehicle according to claim 1, wherein the second case is attached between the step of getting on and off by an operator on the rear side and the case support base between the traveling machine body.
A urea mixing pipe connecting the second case to the first case, and a urea water tank for supplying urea water to the urea mixing pipe,
An anti-vibration support structure for the engine on the traveling machine body, and an exhaust lead-out pipe body that fixes the first case and the urea mixing pipe to the upper position of the engine and is fixed to the traveling machine body side, The work vehicle according to claim 1, wherein a flexible pipe is connected to an exhaust gas outlet side of the urea mixing pipe.
The first case and the urea mixing pipe are disposed on the engine side, the second case is disposed on the traveling machine body side, and an exhaust gas outlet of the urea mixing pipe and an exhaust gas inlet of the second case are disposed. The work vehicle according to claim 5, wherein a flexible pipe is connected therebetween.
The work vehicle according to claim 5, wherein a heat insulating cover body that covers the flexible pipe is provided, and the flexible pipe is disposed below a rear portion of a bonnet that covers the engine.
The exhaust inlet side of the second case is connected to the exhaust outlet side of the first case via the urea mixing pipe, and the engine output shaft core and the exhaust gas movement direction of the first case are parallel to each other. The first case is supported in such a posture that the exhaust gas outlet side of the first case is extended toward one end side of the output shaft of the engine and parallel to the exhaust gas movement direction of the first case. The work vehicle according to claim 5, wherein the urea mixing pipe is supported and an exhaust gas outlet side of the urea mixing pipe is extended toward the other end side of the output shaft of the engine.
A urea mixing pipe connecting the second case to the first case, and a urea water tank for supplying urea water to the urea mixing pipe,
The first case and the urea mixing pipe are arranged on the upper surface side of the engine, and the urea water tank is attached to the front of the traveling body in front of the engine via a tank support. The work vehicle according to claim 1.
A structure in which a water cooling radiator is arranged on the upper surface side of the traveling body in front of the engine, and the urea water tank is attached to the front lower side of the radiator via a tank support and is piped to the side of the radiator. The work vehicle according to claim 9, wherein a urea water injection pump of the urea water tank is connected to a urea water injection nozzle of the urea mixing tube via a pipe.
The fuel tank is arranged below the operation unit, and the fuel tank and the urea water tank are arranged on the same side of the traveling machine body, and the front of the traveling machine body The work according to claim 9, wherein an oil filling port of the fuel tank is installed behind the front wheel of the front part, and a water filling port of the urea water tank is installed in front of the front wheel of the front part of the traveling body. vehicle.
A front PTO shaft is provided at a front portion of the traveling machine body, and a recess into which the front PTO shaft can be loosely inserted is formed on either the upper surface or the bottom surface of the urea water tank, The work vehicle according to claim 9, wherein the front PTO shaft is configured to be inserted into a recess on an upper surface or a bottom surface.