JP2010216332A - Engine and engine device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an engine wherein parts for an intake and exhaust system are efficiently and compactly arranged about a diesel engine 70 with consideration of the performance of the parts. <P>SOLUTION: This engine 70 includes an intake manifold 73 and an exhaust manifold 71, a cooling water pump 159 for cooling water circulation, and an EGR cooler 147 for cooling EGR gas circulated from the exhaust manifold 71 to the intake manifold 73. A cooling water discharge part 173 of the cooling water pump 159 is provided directed to the exhaust manifold 71 side of the engine 70. The EGR cooler 147 is disposed on the exhaust manifold 71 side of the engine 70. A cooling water distribution path 172 connecting the cooling water pump 159 to the EGR cooler 147 is arranged on the exhaust manifold 71 side of the engine 70. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an engine and an engine device provided with an exhaust gas purification device.

  In recent years, due to the application of higher-level exhaust gas regulations related to diesel engines, exhaust gas purification devices that purify air pollutants in exhaust gas are being applied to agricultural machinery, construction machinery, ships, etc., on which diesel engines are mounted. It is being requested to install. As an exhaust gas purification device, DPF (diesel particulate filter), NOx catalyst, etc. are known (refer to patent documents 1 to 3). In addition, as an exhaust gas countermeasure, an EGR device (exhaust gas recirculation device) that recirculates part of the exhaust gas to the intake side is provided, so that the combustion temperature is kept low and the amount of NOx (nitrogen oxide) in the exhaust gas is reduced. The technique of reducing is also known (refer patent document 4).

  In the EGR device of Patent Document 4, a return pipe branched from an exhaust manifold of a diesel engine is connected to the intake manifold. By supplying a part of the exhaust gas (EGR gas) to the intake manifold via the reflux line, the EGR gas and fresh air from the intake side are mixed. The mixed gas is introduced into each cylinder (inside the intake stroke) of the diesel engine.

  In addition, an EGR cooler that uses the cooling water of the diesel engine as a refrigerant is disposed in the reflux pipe. In this case, the EGR gas flowing through the reflux pipe is heat-exchanged by the EGR cooler, and the EGR gas temperature is lowered. As a result, the combustion temperature is kept low while suppressing the generation of black smoke (smoke) during combustion, and the effect of reducing the amount of NOx in the exhaust gas is enhanced.

JP 2000-145430 A Japanese Patent Laid-Open No. 2003-27922 JP 2008-82201 A JP 2000-282916 A

  However, the conventional diesel engine not only cools the diesel engine itself with cooling water, but also cools auxiliary equipment such as EGR coolers, exhaust throttle devices, and oil coolers to protect parts and improve exhaust gas properties. Since water must be circulated, it is necessary to consider an appropriate cooling water distribution system based on the cooling efficiency and the number of parts. The exhaust throttle device is for increasing the exhaust pressure of the diesel engine. By increasing the exhaust gas temperature of the diesel engine by the action of the exhaust throttle device, the diesel engine is warmed up and soot accumulated on the soot filter of the DPF is burned and disappeared. Become.

  In view of this, the present invention has a technical problem to provide an engine device mounted on a work vehicle, which has been improved by examining such a current situation.

  The invention of claim 1 is an engine comprising an intake manifold and an exhaust manifold, a cooling water pump for circulating cooling water, and an EGR cooler for cooling EGR gas recirculated from the exhaust manifold to the intake manifold. A cooling water discharge portion of the cooling water pump is provided toward the exhaust manifold side of the engine, and the EGR cooler is disposed on the exhaust manifold side of the engine, and the cooling water pump And a cooling water flow path connecting the EGR cooler to the exhaust manifold side of the engine.

  According to a second aspect of the present invention, in the engine according to the first aspect, the coolant flow path for the EGR cooler is configured as a separate system from a coolant system to the engine itself, while the output of the engine An oil cooler is disposed on the intake manifold side across the shaft, and the EGR cooler is disposed on the exhaust manifold side.

  According to a third aspect of the present invention, an exhaust gas purification device for purifying exhaust gas is disposed on the side of the engine according to the first or second aspect, and the EGR cooler is disposed on the upper surface side of the exhaust manifold. It is that.

  According to the first aspect of the present invention, the engine includes an intake manifold and an exhaust manifold, a cooling water pump for circulating cooling water, and an EGR cooler for cooling EGR gas that is recirculated from the exhaust manifold to the intake manifold. A cooling water discharge portion of the cooling water pump is provided toward the exhaust manifold side of the engine, and the EGR cooler is disposed on the exhaust manifold side of the engine. Since the cooling water flow path connecting the pump and the EGR cooler is piped to the exhaust manifold side of the engine, the cooling water flow path for the EGR cooler is connected to the cooling water discharge section and the EGR of the cooling water pump. It will be collected on the exhaust manifold side where the cooler is located. Therefore, the cooling water flow path can be easily routed, which can contribute to the improvement of assembly workability.

  According to invention of Claim 2, since the said cooling water flow path with respect to said EGR cooler is comprised in the system | strain different from the cooling water system | strain to the said engine itself, it contributed to cooling of the said engine (temperature rose). ) The cooling water that has reached a high temperature later is not supplied to the EGR cooler. Therefore, the malfunction accompanying the temperature rise of cooling water can be prevented, and the cooling performance of the EGR cooler can be improved. In addition, an oil cooler is disposed on the intake manifold side across the output shaft of the engine, and the EGR cooler is disposed on the exhaust manifold side. Therefore, a cooling water distribution system and an oil cooler for the EGR cooler are disposed. The cooling water distribution system is distributed to both sides across the output shaft. For this reason, arrangement | positioning of each cooling water distribution system is easy to understand, and assembly workability | operativity and maintainability can be improved.

  According to the invention of claim 3, the exhaust gas purification device for purifying the exhaust gas is arranged on the side of the engine according to claim 1 or 2, and the EGR cooler is arranged on the upper surface side of the exhaust manifold. Therefore, the EGR-related members (the EGR cooler, the piping for recirculation, etc.) do not interfere with the mounting position of the exhaust gas purification device, and the EGR-related These members and the like can be arranged, and the piping for reflux can be handled in a compact manner. Therefore, it is possible to further improve the assembly workability and maintainability.

It is front view sectional drawing of DPF. It is the same external appearance bottom view. FIG. 2 is an exploded front sectional view of FIG. 1. It is a front view of the diesel engine of 1st Embodiment which has arrange | positioned DPF ahead of the exhaust manifold. It is a rear view of a diesel engine. It is a top view of a diesel engine. It is a left view of a diesel engine. It is a right view of a diesel engine. It is a front view of the diesel engine which shows the state where DPF was omitted. It is a front view of the diesel engine of 2nd Embodiment which has arrange | positioned DPF above the flywheel housing. It is a top view of a diesel engine. It is a top view of the diesel engine of 3rd Embodiment which connected the exhaust-gas inlet pipe of DPF directly to the exit part of an exhaust manifold. It is a front view of the diesel engine of the reference example which has arrange | positioned DPF above the exhaust manifold. It is front sectional drawing of DPF employ | adopted by the reference example. It is a side view of a backhoe. It is a top view of a backhoe. It is a side view of a forklift car. It is a top view of a forklift car. It is a top view which shows the positional relationship of an oil cooler and an EGR cooler.

  DESCRIPTION OF EMBODIMENTS Embodiments embodying the present invention will be described below with reference to the drawings.

(1). First, the overall structure of the exhaust gas purifying apparatus will be described with reference to FIGS. As shown in FIGS. 1 to 3, a continuously regenerating diesel particulate filter 1 (hereinafter referred to as a DPF) is provided as an exhaust gas purification device. The DPF 1 is for physically collecting particulate matter (PM) and the like in the exhaust gas. The DPF 1 of the embodiment includes a diesel oxidation catalyst 2 such as platinum that generates nitrogen dioxide (NO ₂ ), and a soot filter 3 having a honeycomb structure that continuously oxidizes and removes the collected particulate matter (PM) at a relatively low temperature. Are arranged in series in the moving direction of the exhaust gas (from the left side to the right side in FIG. 1). The DPF 1 is configured so that the soot filter 3 is continuously regenerated. The DPF 1 can reduce carbon monoxide (CO) and hydrocarbons (HC) in the exhaust gas in addition to the removal of particulate matter (PM) in the exhaust gas.

(2). Attachment structure of diesel oxidation catalyst The attachment structure of the diesel oxidation catalyst 2 will be described with reference to FIGS. As shown in FIGS. 1 to 3, a diesel oxidation catalyst 2 as a gas purification filter for purifying exhaust gas discharged from a diesel engine 70 described later is provided in a substantially cylindrical catalyst inner case 4 made of a heat-resistant metal material. ing. The catalyst inner case 4 is made of a heat resistant metal material and is provided in a substantially cylindrical catalyst outer case 5. That is, the catalyst inner case 4 is fitted on the outside of the diesel oxidation catalyst 2 via the mat-shaped ceramic fiber catalyst heat insulating material 6. Further, the catalyst outer case 5 is fitted on the outer side of the catalyst inner case 4 via a thin plate support 7 having an I-shaped end face. Note that the diesel oxidation catalyst 2 is protected by the catalyst heat insulating material 6. The stress (deformation force) of the catalyst outer case 5 transmitted to the catalyst inner case 4 is reduced by the thin plate support 7.

  As shown in FIGS. 1 to 3, a disc-shaped side cover 8 is fixed to one end of the catalyst inner case 4 and the catalyst outer case 5 by welding. A sensor connection plug 10 is fixed to the side lid 8 via a seat plate 9. The one end face 2a of the diesel oxidation catalyst 2 and the left lid 8 are opposed to each other with a predetermined distance L1 for gas inflow space. An exhaust gas inflow space 11 is formed between the left end face 2 a of the diesel oxidation catalyst 2 and the left lid 8. A sensor connection plug 10 is fixed to the exhaust gas inflow space 11 in the catalyst inner case 4 and the catalyst outer case 5. The sensor connection plug 10 is connected to an unillustrated inlet side exhaust gas pressure sensor, an inlet side exhaust gas temperature sensor, and the like.

  As shown in FIGS. 1 and 3, an elliptical exhaust gas inlet 12 is opened at one end of the catalyst inner case 4 and the catalyst outer case 5 in which the exhaust gas inflow space 11 is formed. The elliptical exhaust gas inlet 12 has a short diameter in the exhaust gas movement direction (center line direction of the cases 4 and 5) and a direction orthogonal to the exhaust gas movement direction (circumferential direction of the cases 4 and 5). It has a long diameter. A closing ring body 15 is fixed between the opening edge 13 of the catalyst inner case 4 and the opening edge 14 of the catalyst outer case 5 in a sandwiched manner. A gap between the opening edge 13 of the catalyst inner case 4 and the opening edge 14 of the catalyst outer case 5 is closed by the closing ring body 15. An exhaust ring 15 prevents the exhaust gas from flowing between the catalyst inner case 4 and the catalyst outer case 5.

  As shown in FIGS. 1 and 3, an exhaust gas inlet pipe 16 is disposed on the outer surface of the catalyst outer case 5 in which the exhaust gas inlet 12 is formed. An exhaust connection flange body 17 is welded to a true circular open end 16a on the small diameter side of the exhaust gas inlet pipe 16. Although the details will be described later, the exhaust connection flange body 17 is fastened to the exhaust manifold 71 of the diesel engine 70 via a connecting member 86 having a rigid structure. A large circular opening end 16 b on the large diameter side of the exhaust gas inlet pipe 16 is welded to the outer surface of the catalyst outer case 5. The exhaust gas inlet pipe 16 is formed in a divergent shape (a trumpet shape) from the small-diameter-side perfect circular opening end 16a toward the large-diameter-side perfect circular opening end 16b.

  As shown in FIGS. 1 and 3, a large-diameter opening end 16 b formed in a true circle is formed at one end of the outer surface of the catalyst outer case 5. It is welded to cover. In this case, the exhaust gas inlet pipe 16 (large-diameter-side opening end portion 16b) is offset with respect to the elliptical exhaust gas inlet 12, and is arranged offset to the exhaust gas movement downstream side (the right side of the catalyst outer case 5). Has been. That is, the elliptical exhaust gas inlet 12 is offset to the exhaust gas movement upstream side (the left side of the catalyst outer case 5) with respect to the exhaust gas inlet pipe 16 (large-diameter side opening end portion 16b).

With the above configuration, the exhaust gas of the diesel engine 70 enters the exhaust gas inlet pipe 16 from the exhaust manifold 71, enters the exhaust gas inflow space 11 from the exhaust gas inlet pipe 16 through the exhaust gas inlet 12, and is a diesel oxidation catalyst. 2 is supplied from the left end face 2a. Nitrogen dioxide (NO ₂ ) is generated by the oxidation action of the diesel oxidation catalyst 2.

(3). Soot Filter Mounting Structure The soot filter 3 mounting structure will be described with reference to FIGS. 1 and 3. As shown in FIGS. 1 and 3, the soot filter 3 as a gas purification filter for purifying exhaust gas discharged from the diesel engine 70 is provided in a substantially cylindrical filter inner case 20 made of a heat-resistant metal material. The inner case 4 is made of a heat-resistant metal material and is provided in a substantially cylindrical filter outer case 21. That is, the filter inner case 20 is fitted on the outside of the soot filter 3 via the mat-shaped ceramic fiber filter heat insulating material 22. The soot filter 3 is protected by the filter heat insulating material 22.

  As shown in FIGS. 1 and 3, the catalyst side flange 25 is welded to the exhaust gas movement downstream side (right side) of the catalyst outer case 5. The filter-side flange 26 is welded to the middle of the filter inner case 20 in the exhaust gas movement direction and the end of the filter outer case 21 on the upstream side (left side) of the exhaust gas movement. The catalyst side flange 25 and the filter side flange 26 are detachably fastened by bolts 27 and nuts 28. The diameter of the cylindrical catalyst inner case 4 and the diameter of the cylindrical filter inner case 20 are substantially the same. Further, the diameter of the cylindrical catalyst outer case 5 and the diameter of the cylindrical filter outer case 21 are substantially the same.

  As shown in FIG. 1, in a state where the filter outer case 21 is connected to the catalyst outer case 5 via the catalyst side flange 25 and the filter side flange 26, the exhaust gas movement downstream side (other side) of the catalyst inner case 4 is provided. The end of the filter inner case 20 on the upstream side (one side) of the exhaust gas movement is opposed to the end by being spaced apart by a predetermined sensor mounting interval L2. That is, a sensor mounting space 29 is formed between the end of the catalyst inner case 4 on the downstream side (other side) of the exhaust gas movement and the end of the filter inner case 20 on the upstream side (one side) of the exhaust gas movement. The A sensor connection plug 50 is fixed to the catalyst outer case 5 at the sensor mounting space 29 position. The sensor connection plug 50 is connected to a filter inlet side exhaust gas pressure sensor (not shown), a filter inlet side exhaust gas temperature sensor (thermistor), and the like.

  As shown in FIG. 3, the cylindrical length L4 of the catalyst outer case 5 in the exhaust gas movement direction is longer than the cylindrical length L3 of the catalyst inner case 4 in the exhaust gas movement direction. The cylindrical length L6 of the filter outer case 21 in the exhaust gas movement direction is shorter than the cylindrical length L5 of the filter inner case 20 in the exhaust gas movement direction. The length (L2 + L3 + L5) obtained by adding the fixed interval L2 of the sensor mounting space 29, the cylindrical length L3 of the catalyst inner case 4 and the cylindrical length L5 of the filter inner case 20 is the cylindrical length L4 of the catalyst outer case 5. And a length (L4 + L6) obtained by adding the cylindrical length L6 of the filter outer case 21 to be substantially equal to each other.

  The difference between the lengths of the exhaust gas movement upstream side (one side) of the filter outer case 21 and the exhaust gas movement upstream side (one side) of the filter inner case 20 (L7 = L5−L6). ) Only protrude. That is, when the filter outer case 21 is connected to the catalyst outer case 5, the end of the filter inner case 20 on the upstream side (one side) of the exhaust gas movement is the overlap dimension L7, and the exhaust gas movement downstream of the catalyst outer case 5 It is interpolated to the side (other side).

With the above configuration, nitrogen dioxide (NO ₂ ) generated by the oxidation action of the diesel oxidation catalyst 2 is supplied to the soot filter 3 from the one side end face 3a side. Trapping particulate matter in the exhaust gas of the diesel engine 70 collected by the soot filter 3 (PM) is, by nitrogen dioxide (NO _2), is relatively continuously removed by oxidation at low temperatures. In addition to the removal of particulate matter (PM) in the exhaust gas of the diesel engine 70, carbon monoxide (CO) and hydrocarbons (HC) in the exhaust gas of the diesel engine 70 are reduced.

As described above, the diesel oxidation catalyst 2 and the soot filter 3 are provided as gas purification filters for purifying the exhaust gas discharged from the engine. However, instead of the diesel oxidation catalyst 2 and the soot filter 3, urea (reducing agent) is used. NOx selective reduction catalyst (NOx removal catalyst) for reducing nitrogen oxides (NOx) in the exhaust gas of the engine 70 by ammonia (NH ₃ ) generated by the addition of), and residual ammonia discharged from the NOx selective reduction catalyst An ammonia removal catalyst that removes water may be provided.

As described above, when a NOx selective reduction catalyst (NOx removal catalyst) is provided in the catalyst inner case 4 and an ammonia removal catalyst is provided in the filter inner case 20 as a gas purification filter, nitrogen oxidation in the exhaust gas exhausted by the engine is performed. The substance (NOx) is reduced and can be discharged as harmless nitrogen gas (N ₂ ).

(4). Silencer Mounting Structure With reference to FIGS. 1 to 3, the silencer 30 mounting structure will be described. As shown in FIGS. 1 to 3, the silencer 30 for attenuating the exhaust gas sound discharged from the diesel engine 70 is made of a heat-resistant metal material and a substantially cylindrical silencer inner case 31, and a heat-resistant metal material and a substantially cylindrical shape. The sound-absorbing outer case 32, and the sound-absorbing inner case 31 and the disc-shaped side lid 33 fixed to the right end of the sound-absorbing outer case 32 by welding. A silencer inner case 31 is provided in the silencer outer case 32. The diameter size of the cylindrical catalyst outer case 5, the diameter size of the cylindrical filter outer case 21, and the cylindrical silencing outer case 32 are substantially the same size.

  An exhaust gas outlet pipe 34 is passed through the silencer inner case 31 and the silencer outer case 32. One end side of the exhaust gas outlet pipe 34 is closed by an outlet lid 35. A number of exhaust holes (not shown) are formed in the entire exhaust gas outlet pipe 34 inside the silencer inner case 31. The interior of the muffler inner case 31 communicates with the exhaust gas outlet pipe 34 through the numerous exhaust holes described above. A tail pipe and an existing silencing member (both not shown) are connected to the other end side of the exhaust gas outlet pipe 34.

  In addition, the inside of the muffling inner case 31 is communicated between the muffling inner case 31 and the muffling outer case 32 via a number of muffler holes (not shown). A space between the silencer inner case 31 and the silencer outer case 32 is closed by a side lid 33 or the like. The end of the silencer inner case 31 on the upstream side (one side) of the exhaust gas movement is connected to the end of the silencer outer case 32 on the upstream side (one side) of the exhaust gas movement via a thin plate support (not shown). Has been. With the above configuration, exhaust gas is discharged from the muffler inner case 31 through the exhaust gas outlet pipe 34.

  As shown in FIGS. 1 and 3, a filter-side outlet flange 40 is welded to the exhaust gas movement downstream end (other side) of the filter inner case 20 and the filter outer case 21. The silencer side flange 41 is welded to the exhaust gas movement upstream side (one side) end of the silencer outer case 32. The filter side outlet flange 40 and the silencer side flange 41 are detachably fastened by bolts 42 and nuts 43. A sensor connection plug 44 is fixed to the filter inner case 20 and the filter outer case 21. The sensor connection plug 44 is connected to an unillustrated outlet side exhaust gas pressure sensor, an outlet side exhaust gas temperature sensor (thermistor) and the like.

(5). Next, an intake / exhaust structure of the diesel engine 70 will be described with reference to FIGS. Here, in the following description, the exhaust manifold 71 side of the diesel engine 70 is referred to as “front”, and the intake manifold 73 side is referred to as “back”, and these are used as a reference for the positional relationship between the four sides and the top and bottom in the diesel engine 70 for convenience. Yes.

(5-1). First Embodiment FIGS. 4 to 9 show a first embodiment in which the DPF 1 is disposed in front of the exhaust manifold 71. As shown in FIGS. 4 and 6 to 8, an exhaust manifold 71 is arranged on the front side of the cylinder head 72 in the diesel engine 70. An intake manifold 73 is disposed on the back side of the cylinder head 72. The cylinder head 72 is mounted on a cylinder block 75 having an engine output shaft 74 (crank shaft, see FIGS. 7 and 8) and a piston (not shown). The left and right tip portions of the engine output shaft 74 protrude from the left and right side surfaces of the cylinder block 75, respectively.

  As shown in FIGS. 4 to 7, a flywheel housing 78 is fixed to the left side surface of the cylinder block 75. A flywheel 79 is provided in the flywheel housing 78. A flywheel 79 is pivotally supported on the left end side of the engine output shaft 74. The power of the diesel engine 70 is taken out via the flywheel 79 to the working part of the work vehicle (backhoe 100, forklift 120, etc.).

  An oil pan 95 is arranged on the lower surface of the cylinder block 75. Lubricating oil is stored in the oil pan 95. Lubricating oil in the oil pan 95 is sucked by an oil pump 156 disposed in a portion near the back surface in the cylinder block 75, and an oil cooler 163 disposed in the back surface of the cylinder block 75 (see FIGS. 5 and 8). In addition, the oil is supplied to each lubricating portion of the diesel engine 70 via the oil filter 157. The lubricating oil supplied to each lubricating part is then returned to the oil pan 95. The oil pump 156 is configured to be driven by rotation of the engine output shaft 74. The oil cooler 163 is for cooling the lubricating oil with cooling water. An oil filter 157 is attached to the back surface of the cylinder block 75 via an oil cooler 163 (the oil cooler 163 is interposed between the back surface of the cylinder block 75 and the oil filter 157). In the first embodiment, an oil cooler 163 is disposed on the intake manifold 73 side with an engine output shaft 74 interposed therebetween, and an EGR cooler 147 described later is disposed on the exhaust manifold 71 side (see FIGS. 8 and 19).

  A fuel injection pump 158 for supplying fuel into the combustion chamber in the cylinder block 75 is attached above the oil filter 157 (below the intake manifold 73) on the back surface of the cylinder block 75. The fuel injection pump 158 includes an electronic governor and a fuel feed pump for adjusting the fuel injection amount. By driving the fuel feed pump, the fuel in the fuel tank is sent to the fuel injection pump 158 via the fuel filter.

  A cooling water pump 159 for circulating cooling water is disposed in a portion of the cylinder block 75 near the front of the left side surface. The cooling water pump 159 is configured to be driven by rotation of the engine output shaft 74. Cooling water in a radiator (not shown) mounted on the work vehicle is supplied to the cooling water pump 159 via a thermostat case 160 provided on the top of the cooling water pump 159. Then, by driving the cooling water pump 159, cooling water is supplied to a water cooling jacket (not shown) formed in the cylinder head 72 and the cylinder block 75 to cool the diesel engine 70. The cooling water that has contributed to the cooling of the diesel engine 70 is returned to the radiator (not shown).

  Engine leg mounting portions 96 are provided on both the front and rear side surfaces of the cylinder block 75 and the front and rear side surfaces of the flywheel housing 78, respectively. Each engine leg mounting portion 96 is bolted to an engine leg body 97 having vibration-proof rubber. The diesel engine 70 is supported in an anti-vibration manner on an engine mounting chassis 81 such as a work vehicle (backhoe 100, forklift car 120) via each engine leg 97.

  An inlet portion of the intake manifold 73 protrudes upward from a substantially central portion of the intake manifold 73. And the inlet part of the intake manifold 73 is connected with the air cleaner (illustration omitted) via the collector 145 of the EGR apparatus 91 mentioned later. The fresh air (external air) sucked into the air cleaner is dust-removed and purified by the air cleaner, and then sent to the intake manifold 73 via the collector 145 and supplied to each cylinder of the diesel engine 70.

  As shown in FIGS. 5 and 6, the EGR device 91 (exhaust gas recirculation device) includes a part of exhaust gas of the diesel engine 70 (EGR gas from the exhaust manifold 71) and fresh air (external air from the air cleaner 88). ) Are mixed and supplied to the intake manifold 73, an intake throttle member 146 that causes the collector 145 to communicate with the air cleaner, and a return pipe that is connected to the exhaust manifold 71 via the EGR cooler 147. As a recirculation exhaust gas pipe 148, and an EGR valve member 149 for communicating the collector 145 with the recirculation exhaust gas pipe 148.

  That is, the intake manifold 73 and the intake air intake throttle member 146 are connected via the collector 145. The collector 145 communicates with the outlet side of the recirculation exhaust gas pipe 148 extending from the exhaust manifold 71. As shown in FIG. 6, the collector 145 is formed in a long cylindrical shape. The intake throttle member 146 is bolted to one end of the collector 145 in the longitudinal direction. A downward opening end formed in a portion of the collector 145 opposite to the intake throttle member 146 is detachably bolted to the inlet portion of the intake manifold 73.

  In the first embodiment, the outlet side of the recirculation exhaust gas pipe 148 is connected to the collector 145 via the EGR valve member 149. The EGR valve member 149 adjusts the supply amount of EGR gas to the collector 145 by adjusting the opening degree of an EGR valve (not shown) in the EGR valve member 149. An opening end portion that protrudes obliquely downward from the outer peripheral surface of the EGR valve member 149 is connected to a longitudinal middle portion of the collector 145. The inlet side of the recirculation exhaust gas pipe 148 is connected to the exhaust manifold 71 via an EGR cooler 147.

  As shown in FIGS. 5 and 6, the intake throttle member 146 and the EGR valve member 149 are assembled to a common collector 145. In other words, the intake throttle member 146, the collector 145, and the EGR valve member 149 are unitized as one member. The intake throttle member 146, the collector 145, and the EGR valve member 149 are positioned (exposed) on the intake manifold 73.

  With the above configuration, fresh air (external air) is supplied from the air cleaner to the collector 145 via the intake throttle member 146, while EGR gas (from the exhaust manifold 71 is supplied from the exhaust manifold 71 to the collector 145 via the EGR valve 149. A part of the exhaust gas discharged). After fresh air from the air cleaner and EGR gas from the exhaust manifold 71 are mixed in the collector 145, the mixed gas in the collector 145 is supplied to the intake manifold 73. That is, a part of the exhaust gas discharged from the diesel engine 70 to the exhaust manifold 71 is recirculated from the intake manifold 73 to the diesel engine 70, so that the maximum combustion temperature at the time of high load operation is lowered. NOx (nitrogen oxide) emissions are reduced.

  As shown in FIGS. 4 and 6 to 8, the DPF 1 is disposed in front of the exhaust manifold 71. In this case, the outlet portion of the exhaust manifold 71 protrudes forward (laterally) from the left end side. An exhaust gas inlet pipe 16 and an exhaust gas outlet pipe 34 are provided so as to project from one end side in the longitudinal direction and the other end side in the longitudinal direction of the DPF 1. A forward projecting outlet portion of the exhaust manifold 71 is detachably connected to the exhaust gas inlet pipe 16 on one end side in the longitudinal direction of the DPF 1 through a connecting member 86 having a rigid structure. In the first embodiment, the three parts of the outlet portion of the exhaust manifold 71, the connecting member 86, and the exhaust connection flange body 17 of the exhaust gas inlet pipe 16 are fastened together with bolts. Therefore, the above-described DPF 1 is supported by the highly rigid exhaust manifold 71 via the connecting member 86 having a rigid structure.

  As shown in FIGS. 4 and 6, the DPF 1 of the first embodiment is arranged in a posture extending in a direction parallel to the engine output shaft 74, and the exhaust gas movement direction is the engine output in front of the exhaust manifold 71. It is arranged so as to face the exhaust manifold 71 so as to be appropriately separated from the front surface of the diesel engine 70 so as to be parallel to the shaft 74. Therefore, the upper surfaces of the cylinder head 72, the exhaust manifold 71, and the intake manifold 73 are exposed, and maintenance work is easy.

  As described above, the exhaust gas inlet pipe 16 on one end in the longitudinal direction of the DPF 1 is connected to the outlet portion on the left end side of the exhaust manifold 71 via the connecting member 86, so that the DPF 1 is connected to the diesel engine 70. The engine output shaft 74 is disposed within a lateral width in the direction of the engine output shaft 74. As a result, when the diesel engine 70 is viewed from the intake manifold 73 side (see FIG. 5), most of the DPF 1 is hidden by the diesel engine 70.

  As shown in FIG.6 and FIG.7, the front end side of the 1st leg bracket 19a as a supporting leg body is detachably fastened to the seat board body 9 located in the longitudinal direction one end side of DPF1 with the volt | bolt. The base end side of the first leg bracket 19a is detachably fastened to the left side surface of the cylinder head 72 on the flywheel housing 78 with a bolt. Further, as shown in FIGS. 6 and 8, the front end side of the second leg bracket 19b as a support leg is detachably fastened to the filter side outlet flange 40 near the other end in the longitudinal direction of the DPF 1 with a bolt. ing. The base end side of the second leg bracket 19b is detachably fastened to the front surface of the cylinder head 72 on the exhaust manifold 71 side with a bolt.

  The rigid connection member 86 interposed between the outlet portion of the exhaust manifold 71 and the exhaust gas inlet pipe 16 of the DPF 1 may simply have an exhaust gas passage inside. The connecting member 86 incorporates an exhaust throttle valve 87 (see FIG. 9) for adjusting the exhaust pressure of the diesel engine 70. When soot accumulates on the soot filter 3, the exhaust pressure of the diesel engine 70 is increased by the operation control of the exhaust throttle valve 87 in the connecting member 86, and the exhaust gas temperature from the diesel engine 70 is increased. By doing so, the soot deposited on the soot filter 3 can be burned. As a result, the soot disappears and the soot filter 3 is regenerated.

  Therefore, when the exhaust throttle valve 87 is built in the connecting member 86, the exhaust pressure by the exhaust throttle valve 87 is maintained even when an operation in which the load is small and the temperature of the exhaust gas tends to decrease (operation in which soot is likely to accumulate) is continued. Thus, the soot filter 3 can be regenerated by the forced increase, and the exhaust gas purification ability of the DPF 1 can be properly maintained. Further, a burner or the like for burning the soot deposited on the soot filter 3 becomes unnecessary. Further, when the diesel engine 70 is started, if the exhaust pressure of the diesel engine 70 is increased by controlling the operation of the exhaust throttle valve 87 and the exhaust gas temperature from the diesel engine 70 is increased, the diesel engine 70 is warmed up. Can promote.

  Further, since the connecting member 86 is located upstream of the DPF 1 in the exhaust gas movement direction, the connecting member 86 is replaced with an inlet side exhaust gas pressure sensor, an inlet side exhaust gas temperature sensor, etc. (Not shown) may be connected. A heater for directly increasing the temperature of the exhaust gas sent to the DPF 1 may be built in the connecting member 86. The length of the connecting member 86 in the exhaust gas movement direction is preferably set as short as possible so that the distance between the outlet of the exhaust manifold 71 and the exhaust gas inlet pipe 16 of the DPF 1 is as short as possible.

  The exhaust gas that has moved from the outlet of the exhaust manifold 71 into the DPF 1 via the exhaust gas inlet pipe 16 is purified by the DPF 1 and then moved from the exhaust gas outlet pipe 34 to the tail pipe (not shown). Eventually it will be discharged out of the machine.

  As shown in FIGS. 4 and 6 to 9, an EGR cooler 147 that cools the EGR gas using the cooling water of the diesel engine 70 as a refrigerant is disposed above the exhaust manifold 71 in the front surface of the cylinder head 73. ing. Although details are omitted, the EGR cooler 147 has a known structure including a cylindrical outer case and a plurality of heat exchange tubes provided in the outer case. The internal space of each heat exchange tube communicates with the EGR gas inlet 168 and the outlet 169 of the EGR cooler 147 (outer case).

  As shown in FIGS. 6 to 9, the EGR gas inlet 168 of the EGR cooler 147 is connected to the exhaust manifold 71 through a cylindrical EGR gas take-out pipe 177. The EGR gas outlet 169 is connected in communication with the inlet side of the recirculation exhaust gas pipe 148. The recirculation exhaust gas pipe 148 is routed on the upper surface side of the cylinder head 72, and the outlet side thereof is connected to the collector 145 via the EGR valve member 149. The EGR gas appropriately cooled after passing through the EGR cooler 147 is sent from the EGR gas outlet 169 to the recirculation exhaust gas pipe 148 via the EGR gas discharge pipe 183 in the cylindrical part 182, and to the intake manifold 73 side. Supplied.

  The EGR cooler 147 (outer case) is provided with a cooling water inlet portion 170 and a cooling water outlet portion 171 that communicate with the surrounding space of each heat exchange tube. By filling the periphery of each heat exchange tube with the cooling water supplied from the cooling water inlet 170 into the outer case, the EGR gas flowing through each heat exchange tube is heat-exchanged, and the EGR gas temperature decreases. . As a result, the combustion temperature is kept low while suppressing the generation of black smoke (smoke) during combustion, and the effect of reducing the amount of NOx in the exhaust gas is enhanced. The cooling water supplied into the EGR cooler 147 is discharged from the cooling water outlet 171.

  As shown in detail in FIG. 9, a cooling water flow path 172 from the cooling water pump 159 to the EGR cooler 147 is provided on the front side (exhaust manifold 71 side) of the diesel engine 70. The cooling water from the cooling water pump 159 is configured not only to be supplied to a water cooling jacket (not shown) of the diesel engine 70 but also to supply a part to the cooling water flow path 172. That is, the cooling water flow path 172 is configured as a separate system from the cooling water system (path toward the water cooling jacket) to the diesel engine 70 itself.

  In this case, a cooling water discharge portion 173 (also referred to as a discharge port) protruding from the cooling water pump 159 to the exhaust manifold 71 side (front side) is connected to the cooling water inlet portion 170 of the EGR cooler 147 via the feed pipe 174. Communication connection is established. The cooling water outlet 171 of the EGR cooler 147 is connected to the thermostat case 160 through a return pipe 176. Therefore, a part of the cooling water from the cooling water pump 159 is supplied from the EGR cooler 147 to the thermostat case 160 and circulates.

  As is clear from the above description and FIGS. 4 and 6 to 8, the diesel engine 70 having the intake manifold 73 and the exhaust manifold 71 and the DPF 1 for purifying exhaust gas from the diesel engine 70 are provided. The engine device is mounted on a work vehicle, and the outlet of the exhaust manifold 71 projects forward (laterally), and the exhaust gas inlet pipe 16 and the exhaust gas are disposed at one end in the longitudinal direction and the other end in the longitudinal direction of the DPF 1. The outlet pipes 34 are provided so as to be distributed, and the exhaust gas inlet pipe 16 is connected to the outlet portion of the exhaust manifold 71 so that the DPF 1 is positioned in front (side) of the diesel engine 70.

  For this reason, the DPF 1 communicates with the exhaust manifold 71 at a close distance, and the exhaust gas from the diesel engine 70 can be supplied to the DPF 1 without much temperature decrease. Therefore, it is easy to maintain the DPF 1 at an appropriate temperature, and the exhaust gas purification performance is improved. Since the exhaust gas purification performance is improved, the size of the diesel oxidation catalyst 2 and the soot filter 3 can be reduced, and the DPF 1 can be reduced in size and size. Further, since the exhaust gas inlet pipe 16 is connected to the outlet of the exhaust manifold 71 and the DPF 1 is positioned in front (side) of the diesel engine 70, the exhaust manifold 71 that is a highly rigid part of the diesel engine 70 is provided. By utilizing this, the DPF 1 can be supported with high rigidity, and damage to the DPF 1 due to vibration or the like can be suppressed.

  As is apparent from the above description and FIG. 6, the rigid connecting member 86 is interposed between the outlet of the exhaust manifold 71 and the exhaust gas inlet pipe 16 of the DPF 1. Thus, the connection strength between the exhaust manifold 71 and the DPF 1 can be improved. Accordingly, the DPF 1 can be firmly supported by the exhaust manifold 71 (including the connecting member 86).

  As is clear from the above description and FIGS. 6 to 8, the cylinder head 72 of the diesel engine 70 includes the first and second leg brackets 19 a and 19 b that support the DPF 1. Since it is connected to the cylinder head 72 via the two-leg brackets 19a and 19b and is located in front (side) of the exhaust manifold 71, the exhaust manifold 71 and the first and second leg brackets 19a and 19b are used. Due to the support, the DPF 1 can be connected to the front (side) of the exhaust manifold 71 with high rigidity and stability. Therefore, it is highly effective in preventing damage to the DPF 1 due to vibration or the like.

  Further, since it is possible to ship the DPF 1 incorporated in the diesel engine 70 at the manufacturing site of the diesel engine 70, there is an advantage that the diesel engine 70 and the DPF 1 can be configured in a compact manner. When the diesel engine 70 is mounted in the engine room of a work vehicle (backhoe 100, forklift car 120), etc., when the front side of the exhaust manifold 71 is provided in the engine room, the configuration of the first embodiment is adopted. Is preferred.

  6 and 9, the diesel engine 70 having the intake manifold 73 and the exhaust manifold 71, the cooling water pump 159 for circulating the cooling water, and the EGR that recirculates from the exhaust manifold 71 to the intake manifold 73. An EGR cooler 147 for cooling the gas, a cooling water discharge portion 173 of the cooling water pump 159 is provided toward the exhaust manifold 71 side of the diesel engine 70, and an exhaust manifold of the diesel engine 70 The EGR cooler 147 is disposed on the 71 side, and the cooling water flow path 172 that connects the cooling water pump 159 and the EGR cooler 147 is piped to the exhaust manifold 71 side of the diesel engine 70. Distribution channel 172 So that each occupies a side exhaust manifold 71 with a cooling water discharge portion 173 and EGR cooler 147 却水 pump 159. Therefore, the cooling water flow path 172 can be easily routed, which can contribute to an improvement in assembly workability.

  As is clear from the above description and FIGS. 6 and 9, the cooling water flow path 172 for the EGR cooler 147 is configured as a separate system from the cooling water system (path to the water cooling jacket) to the diesel engine 70 itself. Therefore, the cooling water having a high temperature after contributing to the cooling of the diesel engine 70 (the temperature has increased) is not supplied to the EGR cooler 147. Therefore, the malfunction accompanying the temperature rise of cooling water can be prevented, and the cooling performance of the EGR cooler 147 can be improved. In addition, in plan view, the oil cooler 163 is disposed on the intake manifold 73 side with the engine output shaft 74 of the diesel engine 70 interposed therebetween, and the EGR cooler 147 is disposed on the exhaust manifold 71 side. The cooling water distribution system for the oil cooler and the cooling water distribution system for the oil cooler 163 are distributed to both the front and rear sides with the engine output shaft 74 interposed therebetween. For this reason, arrangement | positioning of each cooling water distribution system is easy to understand, and assembly workability | operativity and maintainability can be improved.

  As is apparent from the above description and FIGS. 6 and 9, the DPF 1 for purifying exhaust gas from the diesel engine 70 is disposed in front (side) of the diesel engine 70, and the EGR cooler 147 is disposed in the exhaust manifold. 71, the mounting position of the DPF 1 does not interfere with the EGR device 91 related members (recirculation exhaust gas pipe 148, EGR cooler 147, etc.), and the diesel engine 70 (cylinder head) 72), the collector 145, the EGR cooler 147, and the like can be arranged, and the recirculated exhaust gas pipe 148 can be handled in a compact manner. Therefore, it is possible to further improve the assembly workability and maintainability.

(5-2). Second Embodiment FIGS. 10 and 11 show a second embodiment in which the DPF 1 is arranged above the flywheel housing 78. The second embodiment is different from the first embodiment only in that the DPF 1 is disposed above the flywheel housing 78, and the other configurations are the same as those of the first embodiment.

  That is, in the second embodiment, the outlet portion of the exhaust manifold 71 protrudes leftward (laterally) from the left end side. A leftward projecting outlet portion of the exhaust manifold 71 is detachably connected to the exhaust gas inlet pipe 16 on one end side in the longitudinal direction of the DPF 1 via a connecting member 86 having a rigid structure. The outlet manifold 71, the connecting member 86, and the exhaust connection flange body 17 of the exhaust gas inlet pipe 16 are fastened together with bolts.

  As shown in FIGS. 10 and 11, the DPF 1 of the second embodiment is arranged in a posture extending in a direction orthogonal to the engine output shaft 74, and the exhaust gas movement direction is above the flywheel housing 78. It is arranged so as to face the cylinder head 72 so as to be appropriately separated from the left side surface of the diesel engine 70 so as to be orthogonal to the output shaft 74. Therefore, also in the case of the second embodiment, the upper surfaces of the cylinder head 72, the exhaust manifold 71, and the intake manifold 73 are exposed, and the maintenance work is easily performed.

  As shown in FIGS. 10 and 11, the distal end side of the third leg bracket 19 c as a support leg is fixed to the center in the longitudinal direction of the DPF 1 by welding or the like. The base end side of the third leg bracket 19c is detachably fastened to the DPF attachment portion 82 of the flywheel housing 78 with a bolt from above.

  Even when configured as in the second embodiment, since the DPF 1 communicates with the exhaust manifold 71 at a very short distance, the same operational effects as in the first embodiment can be achieved. In particular, in the second embodiment, the third leg bracket 19c as a support leg for supporting the DPF 1 is provided on the upper part of the flywheel housing 78 in the diesel engine 70, and the DPF 1 is connected to the flywheel via the third leg bracket 19c. Since it is connected to the wheel housing 78 and is located above the flywheel housing 78, the DPF 1 is supported by the flywheel housing 78 by support using the exhaust manifold 71 (including the connecting member 86) and the third leg bracket 19 c. Can be stably connected with high rigidity (side of the diesel engine 70). Therefore, the configuration of the second embodiment also exhibits a high effect in preventing damage to the DPF 1 due to vibration or the like. When the diesel engine 70 is mounted in the engine room of a work vehicle (backhoe 100, forklift car 120) or the like, the configuration of the second embodiment is employed when there is a margin above the flywheel housing 78 in the engine room. Is preferable.

(5-3). Third Embodiment FIG. 12 shows a third embodiment in which the exhaust gas inlet pipe 16 of the DPF 1 is directly connected to the outlet portion of the exhaust manifold 71. The third embodiment is the same as the second embodiment in that the DPF 1 is disposed above the flywheel housing 78, but the connecting member 86 is omitted and the exhaust gas inlet pipe 16 of the DPF 1 is connected to the exhaust manifold 71. The second embodiment is different from the second embodiment in that it is directly connected to the outlet. Other configurations are the same as those of the first and second embodiments. Even when configured as in the third embodiment, since the DPF 1 communicates with the exhaust manifold 71 at a close distance, the same operational effects as those of the first and second embodiments can be obtained. In the configuration of the first embodiment, it goes without saying that the connecting member 86 may be omitted and the exhaust gas inlet pipe 16 of the DPF 1 may be directly connected to the outlet portion of the exhaust manifold 71.

(5-4). Reference Example FIGS. 13 and 14 show a reference example in which the DPF 200 is disposed above the exhaust manifold 71. In the reference example, the DPF 200 is disposed above the exhaust manifold 71, the EGR cooler 147 is disposed below the exhaust manifold 71, and the shape of the exhaust gas inlet pipe 225 in the DPF 200 is the first to third. This is different from the embodiment. Other configurations are basically the same as those of the first to third embodiments.

  That is, in the reference example, the outlet portion of the exhaust manifold 71 protrudes upward from the central portion. An upward projecting outlet portion of the exhaust manifold 71 is detachably connected to a downward opening end portion 225a of the exhaust gas inlet pipe 225 at a midway portion in the longitudinal direction of the DPF 200 via a connecting member 86 having a rigid structure. The outlet flange of the exhaust manifold 71, the connecting member 86, and the connecting flange body 227 of the exhaust gas inlet pipe 225 are fastened together with bolts.

  As shown in FIG. 13, the DPF 200 of the reference example is arranged in a posture extending in a direction parallel to the engine output shaft 74, and the exhaust gas moving direction is parallel to the engine output shaft 74 above the exhaust manifold 71. The cylinder head 72 is disposed so as to be separated from the upper part of the diesel engine 70 as appropriate. The tip end side of the fourth leg bracket 19d is detachably fastened with a bolt to one end side in the longitudinal direction of the DPF 200. The base end side of the fourth leg bracket 19 d is fastened to the left side surface of the cylinder head 72 on the flywheel housing 78 by a bolt. Moreover, the front end side of the 5th leg bracket 19e is fastened to the other end side of DPF1 in the longitudinal direction so that attachment or detachment is possible with the volt | bolt. The base end side of the fifth leg bracket 19e is detachably fastened to the front face of the cylinder head 72 on the exhaust manifold 71 side with a bolt.

  As shown in FIG. 14, a DPF 200 includes a soot filter which is a filter body having a honeycomb structure and a diesel oxidation catalyst 204 such as platinum, for example, in a substantially cylindrical filter case 202, 203 built in a DPF casing 201 made of a refractory metal material. 205 is accommodated in series.

  On one end side in the longitudinal direction of the DPF casing 201, a circular exhaust gas intake opening 226 that faces a space upstream of the exhaust gas movement from the diesel oxidation catalyst 103 is formed. An exhaust gas inlet pipe 225 that communicates with the exhaust gas intake opening 226 is welded and fixed to one end in the longitudinal direction of the outer surface of the DPF casing 201. As shown in detail in FIG. 14, the exhaust gas inlet pipe 225 is formed in a half cylinder shape opened upward. The rectangular upward opening end 225 b is fixed to the outer surface of the DPF casing 201 by welding so as to cover the exhaust gas intake opening 226 and extend in the longitudinal (front-rear) direction of the DPF casing 201.

  A downward opening end 225a that is an exhaust gas inlet is formed on the front end side of the exhaust gas inlet pipe 225 that corresponds to a midway portion of the DPF casing 201 in the longitudinal direction. A connecting flange body 227 is fixed to the outer periphery of the downward opening end 225a by welding. The connection flange body 227 is fastened to an upward projecting outlet portion of the exhaust manifold 71 via a connection member 86 having a rigid structure. The downward opening end portion 225 a of the exhaust gas inlet pipe 225 is located at a substantially central portion in the longitudinal direction of the DPF casing 201. For this reason, the length of the DPF 201 in the exhaust gas movement direction is a dimension that is substantially equally divided across the downward opening end 225a of the exhaust gas inlet pipe 225.

  On the other end side in the longitudinal direction of the DPF casing 201, a circular exhaust gas discharge opening 229 is formed that faces a space on the downstream side of the exhaust gas movement from the soot filter 205. An exhaust gas outlet pipe 228 communicating with the exhaust gas discharge opening 229 is provided on the outer surface of the DPF casing 201. The exhaust gas outlet pipe 228 is connected to a tail pipe, an existing silencing member (both not shown), and the like.

(6). Mounting structure of diesel engine on backhoe A structure in which the diesel engine 70 of the first embodiment is mounted on the backhoe 100 will be described with reference to FIGS. 15 and 16. It goes without saying that the diesel engine 70 of the second and third embodiments and the reference example can also be mounted on the backhoe 100 if the size and shape of the engine room allow.

  As shown in FIGS. 15 and 16, the backhoe 100 includes a crawler-type traveling device 102 having a pair of left and right traveling crawlers 103, and a turning machine body 104 provided on the traveling device 102. The revolving machine body 104 is configured to be horizontally revolved over 360 ° in all directions by a revolving hydraulic motor (not shown). An earthwork plate 105 for ground work is mounted on the rear part of the traveling device 102 so as to be movable up and down. A steering unit 106 and a diesel engine 70 are mounted on the left side of the revolving machine body 104. A working unit 110 having a boom 111 and a bucket 113 for excavation work is provided on the right side of the revolving machine body 104.

  The control unit 106 is provided with a control seat 108 on which an operator is seated, operation means for operating the diesel engine 70 and the like, and a lever or switch as an operation means for the work unit 110. A boom cylinder 112 and a bucket cylinder 114 are arranged on a boom 111 which is a component of the working unit 110. A bucket 113 as an attachment for excavation is pivotally attached to the tip end portion of the boom 111 so as to be inserted and rotated. The boom cylinder 112 or the bucket cylinder 114 is operated to perform earthwork work (ground work such as grooving) by the bucket 113.

(7). Mounting structure of diesel engine on forklift car A structure in which the diesel engine 70 of the first embodiment is mounted on a forklift car 120 will be described with reference to FIGS. 17 and 18. Needless to say, the diesel engine 70 of the second and third embodiments and the reference example can also be mounted on the forklift car 120 if the size and shape of the engine room allow.

  As shown in FIGS. 17 and 18, the forklift car 120 includes a traveling machine body 124 having a pair of left and right front wheels 122 and a rear wheel 123. The traveling body 124 is equipped with a control unit 125 and a diesel engine 70. The diesel engine 70 is covered from above with a cover body 133, and the control unit 125 is provided on the cover body 133.

  A working unit 127 having a fork 126 for cargo handling work is provided on the front side of the traveling machine body 124. On the rear side of the traveling machine body 124, a counterweight 131 for balancing the weight with the working unit 127 is provided. The control unit 125 is provided with a control seat 128 on which an operator is seated, a control handle 129, levers and switches as operation means for the diesel engine 70 and the working unit 127, and the like.

  A fork 126 is mounted on the mast 130, which is a component of the working unit 127, so as to be movable up and down. The fork 126 is moved up and down, a pallet (not shown) loaded with a load is placed on the fork 126, the traveling machine body 124 is moved forward and backward, and a cargo handling operation such as transportation of the pallet is performed. Yes.

  The diesel engine 70 is disposed such that the flywheel housing 78 is located on the front side of the traveling machine body 124. That is, the diesel engine 70 is arranged so that the direction of the engine output shaft 74 is along the front-rear direction in which the working unit 127 and the counterweight 131 are arranged. The diesel engine 70 is supported in an anti-vibration manner via an engine leg 97 on an engine mounting chassis 81 constituting the traveling machine body 124. A mission case 132 is connected to the front side of the flywheel housing 78. The power from the diesel engine 70 via the flywheel 79 is appropriately changed in the transmission case 132 and transmitted to the hydraulic drive sources of the front wheels 122, the rear wheels 123, and the forks 126.

  In addition, this invention is not limited to the above-mentioned embodiment, It can be embodied in various aspects. For example, the engine device for mounting the work vehicle according to the present invention is not limited to the backhoe 100 and the forklift car 120 as described above, but various work vehicles such as agricultural work machines such as a combine and a tractor, and special work vehicles such as a crane truck. Widely applicable to. Moreover, the structure of each part in this invention is not limited to embodiment of illustration, A various change is possible in the range which does not deviate from the meaning of this invention.

1,200 DPF (gas purification filter)
19a to 19e Leg brackets 70 as support legs Diesel engine 71 Exhaust manifold 72 Cylinder head 73 Intake manifold 78 Flywheel housing 86 Connecting member 91 EGR device 147 EGR cooler 148 Recirculated exhaust gas pipe 163 Oil cooler 159 Cooling water pump 172 Cooling Water distribution path 177 EGR gas outlet pipe

Claims (3)

An engine comprising an intake manifold and an exhaust manifold, a cooling water pump for circulating cooling water, and an EGR cooler for cooling EGR gas to be recirculated from the exhaust manifold to the intake manifold,
A cooling water discharge portion of the cooling water pump is provided toward the exhaust manifold side of the engine, and the EGR cooler is disposed on the exhaust manifold side of the engine. A cooling water flow path connecting the EGR cooler is piped to the exhaust manifold side of the engine.
engine. The coolant flow path for the EGR cooler is configured as a separate system from the coolant system to the engine itself, and an oil cooler is disposed on the intake manifold side across the output shaft of the engine. The EGR cooler is disposed on the exhaust manifold side.
The engine according to claim 1. An exhaust gas purification device for purifying exhaust gas is disposed on the side of the engine according to claim 1 or 2, and the EGR cooler is disposed on an upper surface side of the exhaust manifold.
Engine equipment.

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