Engine equipment

Abstract

To provide a compact layout for the turbocharger and its related parts. The engine device includes a turbocharger provided on the exhaust side of the engine device and an intake pipe connected to the turbocharger. The intake pipe has a bent portion. An inclined portion is provided on the intake upstream side of the bent portion.

Description

[Technical Field]

[0001] The present invention relates to an engine device equipped with a supercharger. [Background technology]

[0002] Conventionally, engine devices have been equipped with turbochargers that compress fresh air using exhaust energy to increase the air density inside the cylinders of engines in order to improve engine output and fuel economy (see Patent Document 1). In diesel engines, supplying a large amount of high-density air into the cylinders not only increases engine output and engine torque by burning a large amount of fuel, but also promotes mixing of fuel and air, thereby suppressing premixed combustion and reducing NOx (nitrogen oxide) emissions. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-133796 Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, the space available for mounting an engine varies depending on the work vehicle (construction machinery, agricultural machinery, etc.) on which it is to be mounted, but in recent years, due to demands for lighter weight and more compactness, mounting space is often restricted (narrow). For this reason, it is necessary to layout the engine components compactly. In particular, when a turbocharger is mounted on a small-displacement engine, the turbocharger takes up a large proportion of the engine surface, so it is necessary to layout the turbocharger and its related parts compactly.

[0005] The present invention has as its technical object to provide an engine device that has been improved by examining the current situation as described above. [Means for solving the problem]

[0006] The engine device of the present invention includes a turbocharger provided on an exhaust side of the engine device, and an intake pipe connected to the turbocharger. The intake pipe has a bent portion. An inclined portion is provided on the intake upstream side of the bent portion. [Effects of the Invention]

[0007] According to the engine device of the present invention, the turbocharger and its related parts can be laid out in a compact manner. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. [Figure 2] FIG. [Figure 3] FIG. [Figure 4] FIG. [Figure 5] FIG. [Figure 6] FIG. 2 is a perspective view of the engine as seen obliquely from the front. [Figure 7] FIG. 2 is a perspective view of the engine as seen obliquely from the rear. [Figure 8] FIG. 2 is a plan view showing a partial cross section of the intake manifold with an integrated valve arm chamber. [Figure 9] FIG. 2 is a left cross-sectional view of an intake manifold with an integrated valve arm chamber. [Figure 10] FIG. 2 is a rear cross-sectional view of the intake manifold with integrated valve arm chamber. [Figure 11] FIG. 2 is a perspective view showing a cross section of an intake manifold integrated with a valve arm chamber. [Figure 12] FIG. 2 is a perspective view showing a cross section of the arm chamber of the intake manifold and a blow-by gas reduction device. [Figure 13] FIG. 2 is a perspective view of the intake manifold with integrated valve arm chamber as seen from the bottom side. [Figure 14] FIG. 2 is a perspective view showing a cross section of the blow-by gas reduction device. [Figure 15]FIG. 2 is a plan view showing the configuration of the intake pipe and its surroundings. [Figure 16] FIG. 2 is a front view showing the configuration of the intake pipe and its surroundings. [Figure 17] FIG. 2 is a perspective view showing the configuration of the intake pipe and its surroundings. [Figure 18] FIG. 2 is a perspective view showing an intake manifold with an integrated valve arm chamber, an intake pipe, and a blow-by gas return pipe. [Figure 19] FIG. 2 is a perspective view showing an intake pipe and a blow-by gas return pipe in cross section. [Figure 20] FIG. 2 is a left side view showing exhaust system components. [Figure 21] FIG. 2 is a perspective view showing exhaust system components. [Figure 22] FIG. 2 is an exploded perspective view showing the mounting structure of the exhaust system components. [Figure 23] FIG. 2 is a rear view showing the cylinder block together with exhaust system components, partially in cross section. DETAILED DESCRIPTION OF THE INVENTION

[0009] An embodiment of the present invention will be described below with reference to the drawings. First, a schematic structure of an engine (engine device) 1 will be described with reference to Figures 1 to 7. In the following description, both sides along the output shaft 3 (both sides along the output shaft 3) will be referred to as the left and right, the side where the cooling fan 9 is located will be referred to as the front side (one side), the side where the flywheel 11 is located will be referred to as the rear side, the side where the exhaust manifold 7 is located will be referred to as the left side (one side), and the side where the fuel injection pump device 14 is located will be referred to as the right side (the other side), and for convenience, these will be used as the basis for the positional relationship between the four sides and the top and bottom of the engine 1.

[0010] As shown in FIGS. 1 to 7 , an engine 1 serving as a prime mover mounted on a work machine such as a construction machine or agricultural machine includes a cylinder block 4 housing an output shaft 3 (crankshaft) and pistons (not shown). A cylinder head 5 is mounted on the cylinder block 4. An exhaust manifold 7 is disposed on the left side of the cylinder head 5. An intake manifold 8 (head cover) with an integrated valve arm chamber is disposed on the top surface of the cylinder head 5. The intake manifold 8 with an integrated valve arm chamber includes an intake manifold section 6 disposed on the left side and extending in the front-rear direction, and an intake manifold section 90 disposed on the right side and extending in the front-rear direction. That is, above the cylinder head 5, the intake manifold section 6 is disposed on the left side of the output shaft 3 of the engine 1, and the intake manifold section 90 is disposed on the right side (near the exhaust manifold 7). The intake manifold section 6 covers the intake valves and exhaust valves (not shown) provided on the top surface of the cylinder head 5.

[0011] A cooling fan 9 is provided on one side of the engine 1 that intersects with the output shaft 3, specifically on the front side of the cylinder block 4. A mounting plate 10 is provided on the rear side of the cylinder block 4. A flywheel 11 is arranged so as to overlap the mounting plate 10. The flywheel 11 is journaled on the output shaft 3. Power from the engine 1 is extracted via the output shaft 3 to the operating section of the work machine. An oil pan 12 is also provided below the cylinder block 4. Lubricating oil in the oil pan 12 is supplied to each lubricated section of the engine 1 via an oil filter 13 located on the right side of the cylinder block 4. The oil pan 12 is connected to the cylinder block 4 via a spacer 71. The spacer 71 extends from the rear end of the cylinder block 4 to below the gear case 54. The gear case 54, which is connected to the front of the cylinder block 4, is also connected to the spacer 71.

[0012] An injector (fuel injection valve) 15 is provided on the right side of the top surface of the cylinder head 5. In this embodiment, the injectors 15 are provided for three cylinders. In the following, this embodiment will be described using a three-cylinder engine 1 as an example, but the number of cylinders in the engine device of the present invention is not limited to three. A fuel tank (not shown) mounted on the work machine is connected to each injector 15 via a fuel injection pump device 14 and a fuel filter 17. The base end of a front hanging bracket 55 is bolted to the left side of the front of the cylinder head 5. The front hanging bracket 55 also serves as a support member for the alternator 23, which will be described later.

[0013] A fuel injection pump device 14 for supplying fuel into the combustion chambers in the cylinder block 4 is attached to the right side of the cylinder block 4 above the oil filter 13 (below the intake manifold section 6). The fuel injection pump device 14 includes an injection pump body 32 that supplies fuel to each injector 15 via a fuel injection pipe 36, a governor housing case 33 that houses a governor that adjusts the fuel injection amount, an actuator section 34 that controls the operation of the governor, and a fuel feed pump 35 that delivers fuel. The governor housing case 33 is an injection pump The actuator unit 34 is detachably fastened with bolts to the rear surface of the main body 32. The actuator unit 34 is detachably fastened with bolts to the rear surface of the governor housing case 33. The fuel feed pump 35 is detachably fastened with bolts to the right side surface of the injection pump main body 32.

[0014] The fuel injection pump device 33 is attached to the engine 1 by having the front surface of the injection pump body 32 detachably fastened with bolts to the rear surface of the gear case 54, and by having the rear surface of the governor housing case 33 detachably fastened with bolts to the rear portion of the right side surface of the cylinder head 5 via an L-shaped pump device bracket 41. The gear case 54, attached to the lower portion of the front surface of the cylinder block 4, houses a gear train (not shown) including a crank gear, cam gear, pump gear, idle gear, etc.

[0015] When the fuel feed pump 35 is driven, fuel in a fuel tank (not shown) is sent from the fuel feed pump 35 through a fuel feed pipe 37, a fuel filter 17, and a fuel relay pipe 38 to the injection pump main body 32. Then, fuel is supplied from the injection pump main body 32 to each injector 15 through a fuel injection pipe 36. A fuel return pipe 39 is connected between the injection pump main body 32 and the fuel filter 17. A fuel return pipe 40, which returns surplus fuel from the injectors 15, joins the fuel return pipe 39 near the injection pump main body 32. Surplus fuel from the engine 1 is returned to the fuel tank (not shown) through the fuel return pipes 39, 40 and a fuel return pipe fitting 57 provided above the fuel filter 17. The base end of a rear hanging bracket 56 is fastened with bolts to the right side of the rear surface of the cylinder head 5. The fuel filter 17 is detachably fastened with bolts to the upper right side of the rear hanging bracket 56.

[0016] An engine starter 18 is provided on the mounting plate 10. A pinion gear of the engine starter 18 meshes with a ring gear of the flywheel 11. When starting the engine 1, the rotational force of the engine starter 18 rotates the ring gear of the flywheel 11, causing the output shaft 3 to start rotating (so-called cranking is performed).

[0017] A cooling water pump 21 is disposed coaxially with the fan shaft of the cooling fan 9 on the front side (cooling fan 9 side) of the cylinder head 5. An alternator 23 serving as a generator that generates electricity using power from the engine 1 is provided on the left side of the engine 1, specifically to the left of the cooling water pump 21. Rotation of the output shaft 3 drives the cooling fan 9, the cooling water pump 21, and the alternator 23 via a cooling fan drive V-belt 22. Cooling water in a radiator 19 mounted on the work machine side is supplied to the interior of the cylinder block 4 and the cylinder head 5 by driving the cooling water pump 21, thereby cooling the engine 1. A portion of the cooling water from the cooling water pump 21 flows through a passage in the cylinder block 4 and cooling water relay pipes 81 and 82 to an oil cooler 83 disposed at the base of the oil filter 13.

[0018] 3 and 4, two engine mount attachment portions 24 are provided at the front and rear of the lower portions of the left and right side surfaces of the cylinder block 4. An engine mount (not shown) having, for example, vibration-isolating rubber can be bolted to each engine mount attachment portion 24. In this embodiment, the cylinder block 4 is sandwiched between a pair of left and right engine support chassis 25 of the work machine, and the engine mount attachment portions 24 are bolted to each engine support chassis 25 via the engine mounts (not shown), so that both engine support chassis 25 of the work machine support the engine 1.

[0019] A radiator 19 with a fan shroud 20 attached to the rear side is erected on the pair of left and right engine support chassis 25 so as to be positioned on the front side of the engine 1. The fan shroud 20 surrounds the outside (outer periphery) of the cooling fan 9, and connects the radiator 19 to the cooling fan 9. As the cooling fan 9 rotates, cooling air is blown onto the radiator 19. Then, the air flows from the radiator 19 to the engine 1 via the fan shroud 20 .

[0020] An air cleaner (not shown) is connected to the inlet of the intake manifold 6 via an intake relay pipe 66, a compressor case 62 of the turbocharger 60, intake pipes 91, 92, etc. Fresh air (outside air) drawn into the air cleaner is cleaned and purified by the air cleaner, and then sent to the intake manifold 6 via the intake pipes 91, 92, the compressor case 62 (details of which will be described later), and the intake relay pipe 66, and is supplied to each cylinder of the engine 1.

[0021] In the above-described configuration, fresh air is supplied from the air cleaner to the intake pipes 91, 92, while blow-by gas is merged into the first intake pipe 91 from the blow-by gas outlet 67 provided in the intake manifold 8 integrated with the arm chamber via the blow-by gas return pipe 68. As described above, the intake manifold 8 integrated with the arm chamber is formed integrally with the intake manifold section 6 formed at the left side of the intake manifold 8 integrated with the arm chamber, and the arm chamber section 90 formed at the right side of the intake manifold 8. In addition, a blow-by gas reduction device 69 that separates lubricating oil from the blow-by gas protrudes from the upper surface of the arm chamber section 90. The blow-by gas provided in the blow-by gas reduction device 69 is returned to the first intake pipe 91 and sent to the combustion chamber again, thereby preventing the blow-by gas containing exhaust gas and unburned air-fuel mixture from being released into the atmosphere.

[0022] A turbocharger 60 is disposed above the exhaust manifold 7 on the left side of the cylinder head 5. The turbocharger 60 includes a turbine case 61 incorporating a turbine wheel, a compressor case 62 incorporating a blower wheel, and a center housing 63 which connects the turbine case 61 and the compressor case 62. A lubricant oil feed pipe 64 (oil feed pipe) which branches off from a lubricant oil feed passage 79 (see FIG. 23) inside the cylinder block 4 and feeds lubricant oil to the rotating parts inside the center housing 63 is connected to the top of the center housing 63. A lubricant oil return pipe 65 which returns the lubricant oil fed into the center housing 63 to a lubricant oil return passage (not shown) inside the cylinder block 4 is connected to the bottom of the center housing 63.

[0023] An exhaust-side inlet 61a of the turbine case 61 is connected to an exhaust gas outlet portion of the exhaust manifold 7. That is, exhaust gas discharged from each cylinder of the engine 1 into the exhaust manifold 7 is released to the outside via the turbocharger 60. Note that, for example, a silencer or a tailpipe is connected to the exhaust-side outlet 61b of the turbine case 61 via an exhaust pipe, and the exhaust gas is discharged to the outside from the exhaust-side outlet 61b of the turbocharger 60 via the silencer or the tailpipe.

[0024] An intake inlet 62a (intake side inlet of the turbocharger) side of the compressor case 62 is connected to the fresh air outlet side of an air cleaner (not shown) via a second intake pipe 92, a first intake pipe 91, etc. An intake outlet 62b (intake side outlet of the turbocharger) side of the compressor case 62 is connected to the intake manifold section 6 of the intake manifold 8 integrated with the valve arm chamber via an intake relay pipe 66. That is, fresh air that has been cleaned of dust by the air cleaner is sent from the compressor case 62 to the intake manifold section 6 via the intake relay pipe 66, and then supplied to each cylinder of the engine 1.

[0025] Next, the configuration of the arm chamber-integrated intake manifold 8 will be described with reference to Figures 8 to 14. As described above, the arm chamber-integrated intake manifold 8 comprises an intake manifold section 6 (intake manifold) arranged to extend in the front-rear direction at a location shifted to the left, and an arm chamber section 90 (arm chamber) arranged to extend in the front-rear direction at a location shifted to the right. In the arm chamber-integrated intake manifold 8, the intake manifold section 6 and the arm chamber section 90 are separated by a partition wall 101, making the intake manifold section 6 and the arm chamber section 90 into mutually closed spaces.

[0026] The upper surface of the intake manifold 6 is covered with an intake lid 102. The intake lid 102 is fixed to the upper surface of the side wall of the intake manifold 6 with screws at two locations, and is fastened to the cylinder head 5 at six locations via the intake manifold 6. The arm chamber-integrated intake manifold 8 is also fastened to the cylinder head 5 with bolts at three locations around the periphery on the arm chamber 90 side.

[0027] An intake inlet 103 protrudes upward from the upper surface of the intake lid portion 102. Furthermore, three intake outlets 104 connected to intake inlets for three cylinders provided on the upper surface of the cylinder head 5 are formed in a row in the front-to-rear direction of the engine 1 on the bottom surface of the intake manifold portion 6. Two injector installation recesses 125 are provided on the right side surface of the intake manifold portion 6. The injector installation recesses 125 are located between adjacent intake outlets 104, 104. That is, in the example of this embodiment, the two injector installation recesses 125 and the three intake outlets 104 are alternately arranged in the intake manifold portion 6 of the intake manifold 8 in the direction along the output shaft 3 of the engine 1.

[0028] The injector installation recess 125 is formed by cutting out a bottom portion of the intake manifold 6 from the right side surface to the partition wall 101. The cylinder head 5 and the injector installation recess 125 form a space for installing the injector 15 that is open on the right side. The injector 15 is inserted into the cylinder head 5 below the injector installation recess 125. Because the right side of the injector installation recess 125 is open, the fuel injection pipe 36 and the fuel return pipes 39, 40 that connect the fuel injection pump device 14 and the injector 15, respectively, installed on the right side of the cylinder head 5, can be installed over short routes, and the piping work can be simplified.

[0029] A blow-by gas return device 69 that returns blow-by gas to the intake system protrudes from the upper part of the arm chamber 90. The blow-by gas return device 69 has a gas outlet portion 111 that is formed by a part of the upper surface of the arm chamber-integrated intake manifold 8 bulging upward. A gas pressure regulating valve 112 is disposed on the upper surface of the gas outlet portion 111. A blow-by gas outlet port 67 is also provided on the left side surface of the gas outlet portion 111.

[0030] A gas leading passage 111a, part of which also serves as a pressure control chamber, and a gas leading passage 111b, part of which is connected to the blow-by gas leading port 67, are formed inside the gas leading portion 111. The gas leading passage 111a extends from a lower portion to an upper portion of the gas leading portion 111 inside the gas leading portion 111. A portion of the gas leading passage 111a is formed in an annular shape at the upper portion of the gas leading portion 111 so as to surround the periphery of the opening of the gas leading passage 111b, and also serves as the pressure control chamber. The gas leading passage 111b is led downward from the upper portion of the gas leading portion 111, and then bent toward the left side of the gas leading portion 111 to be connected to the blow-by gas leading port 67.

[0031] Gas pressure regulating valve 112 includes a valve case 122 and a pressure control diaphragm 123. Valve case 122 is disposed on the upper surface of gas outlet portion 111. Valve element 124 of diaphragm 123 is disposed between gas outlet passage 111a, which also serves as a pressure control chamber, and gas outlet passage 111b, which is connected to blow-by gas outlet port 67. Communication between gas outlet passage 111a and gas outlet passage 111b is normally blocked by valve element 124, but when the pressure in outlet passage 111a exceeds a certain pressure, diaphragm 123 is pressed upward, causing valve element 124 to move upward and open, thereby connecting outlet passages 111a and 111b.

[0032] Within the arm chamber 90, a gas introduction chamber 113 and an internal passage 114 are formed at the bottom of the gas lead-out portion 111. The gas introduction chamber 113 takes in blow-by gas leaking from the combustion chamber of the engine 1 to the upper surface side of the cylinder head 5. The internal passage 114 connects the gas lead-out passage 111a and the gas introduction chamber 113. A shield plate 115 is also provided at the bottom of the gas lead-out portion 111. It is fixed with a screw 117. The bottom side of the gas introduction chamber 113 and the internal passage 114 on the upper side of the arm chamber 90 are closed by a shielding plate 115.

[0033] A cylindrical gas introduction part 116 is fixed to the bottom opening of the gas introduction chamber 113 provided in the shielding plate 115. The gas introduction part 116 is located close to the inner wall of the left side surface within the arm chamber 90. The gas outlet of the gas introduction part 116 is located within the gas introduction chamber 113. The gas inlet of the gas introduction part 116 is located at a position within the arm chamber 90 closer to the cylinder head 5. The gas introduction part 116 is equipped with a cover member at its upper end, and while preventing liquid lubricating oil from directly entering the gas introduction chamber 113 from the cylinder head 5 side, it introduces blow-by gas within the arm chamber 90 from a position within the arm chamber 90 closer to the cylinder head 5 into the gas introduction chamber 113 of the blow-by gas reduction device 69 above.

[0034] A partition wall 118 is provided at the bottom of the gas outlet portion 111 to separate the gas introduction chamber 113 from the internal passage 114. The partition wall 118 is provided spaced apart from a peripheral wall 119 of the blow-by gas reduction device 69, and the gas introduction chamber 113 and the multiple internal passages 114 are formed between the partition wall 118 and the peripheral wall 119. The multiple internal passages 114 are arranged in a maze-like pattern to form a labyrinth structure.

[0035] Oil trap materials 120 such as steel wool that capture lubricating oil mist in the blow-by gas are disposed at two locations between the partition wall 118 and the peripheral wall 119. In this embodiment, the oil trap materials 120 are disposed in the front-to-rear direction of the engine 1, sandwiching the partition wall 118 therebetween. The oil trap materials 120 are disposed between the gas introduction chamber 113 and the internal passage 114.

[0036] As shown in Fig. 9, beam-shaped partition walls 121 that protrude downward are provided on the interior upper surface of gas introduction chamber 113 at two locations on either side of gas introduction section 116. The beam-shaped partition walls 121 are installed between oil trap material 120 and gas introduction chamber 113 at a position higher than oil trap material 120. The space surrounded by peripheral wall 119, the upper surface of oil trap material 120, and beam-shaped partition walls 121 constitutes part of internal passage 114 through which blow-by gas flows.

[0037] The blow-by gas in the valve arm chamber 90 is introduced into the blow-by gas reduction device 69 from the gas outlet portion 111, and is sent to the blow-by gas outlet port 67 via the gas introduction chamber 113, the labyrinth-shaped internal passage 114, the gas outlet passage 111a, the valve body 124 of the diaphragm 123, and the gas outlet passage 111b, while lubricating oil components and the like are removed in each passage and the oil trap material 120. The blow-by gas from which the lubricating oil components and the like have been removed is returned to the intake system from the blow-by gas outlet port 67 through the blow-by gas return pipe 68 (see FIG. 6).

[0038] In the engine 1 of this embodiment, the intake manifold 8 integral with the intake manifold section 6 and the arm chamber 90 is arranged on the top surface of the cylinder head 5, allowing for a compact layout of the intake manifold section 6 and the arm chamber 90. Furthermore, the blow-by gas reduction device 69 is provided to protrude from the upper part of the arm chamber 90, and the blow-by gas is led to the intake side inlet 62a of the turbocharger 60 through a blow-by gas return pipe 68 (gas pipe) connected to a blow-by gas lead-out port 67 provided on the side of the blow-by gas reduction device 69, allowing for a compact layout by arranging the turbocharger 60 and the blow-by gas reduction device 69 close to each other.

[0039] Furthermore, by providing the blow-by gas outlet 67 on the side of the blow-by gas reduction device 69, it is possible to provide a degree of freedom in the arrangement of the blow-by gas return pipe 68 connected to the blow-by gas outlet 67. Furthermore, the blow-by gas reduction device 69 protrudes from the upper part of the valve arm chamber 90. By providing the blow-by gas returning device 69, it is possible to prevent the volume inside the arm chamber 90 from becoming smaller due to the placement of the blow-by gas returning device 69. As a result, it is possible to ensure a sufficient arm chamber volume to cope with the increase in blow-by gas that accompanies the installation of the turbocharger 60, without significantly increasing the volume of the arm chamber 90, and therefore the external dimensions of the arm chamber-integrated intake manifold 8.

[0040] Furthermore, the blow-by gas outlet 67 provided on the side of the blow-by gas reduction device 69 can be disposed close to the turbocharger 60, which simplifies the layout of the blow-by gas return pipe 68 and shortens the piping length. By shortening the length of the blow-by gas return pipe 68, it is possible to prevent the blow-by gas return pipe 68 from becoming clogged due to freezing, bending, or the like.

[0041] Furthermore, in the engine 1 of this embodiment, the multiple internal passages 114 within the blow-by gas reduction device 69 form a maze-like labyrinth structure, and by forming the above-mentioned labyrinth structure within the blow-by gas reduction device 69, the labyrinth structure can be made compact without significantly increasing the volume of the valve arm chamber portion 90, and therefore the external dimensions of the valve arm chamber-integrated intake manifold 8, and the above-mentioned labyrinth structure can remove lubricating oil, unburned fuel, etc. contained in the blow-by gas.

[0042] In addition, in the engine 1 of this embodiment, an oil trap material 120 is arranged between the partition wall 118 that separates the gas introduction chamber 113 and the internal passage 114 and the peripheral wall 119 of the blow-by gas reduction device 69, so that the blow-by gas that bypasses the partition wall 118 and flows from the gas outlet of the gas introduction section 116 to the internal passage 114 can pass through the oil trap material 120, and lubricating oil and the like contained in the blow-by gas can be removed by the oil trap material 120.

[0043] Furthermore, in the engine 1 of this embodiment, the space surrounded by the beam-shaped partition wall 121 erected between the oil trap material 120 and the gas introduction chamber 113 at a position above the oil trap material 120, the upper surface of the oil trap material 120, and the peripheral wall 119 is used as part of the internal passage 114, so that blow-by gas can flow from the gas outlet of the gas introduction section 116 through the gas introduction chamber 113 and the inside of the oil trap material 120 to the upper surface side of the oil trap material 120, and lubricating oil and the like contained in the blow-by gas can be removed by the oil trap material 120.

[0044] Next, the configuration of the intake pipe and its surroundings will be described with reference to Figures 15 to 19. In the engine 1 of this embodiment, a first intake pipe 91, one end (upstream side) of which is connected to an air cleaner (not shown), is disposed between the cooling fan 9 and the blow-by gas outlet 67. Specifically, the first intake pipe 91 is disposed above the cooling water pump 21 on the front side (one of the front and rear sides) of the engine 1. One end of the first intake pipe 91 forms a fresh air inlet 91a.

[0045] The first intake pipe 91 is made of, for example, metal and has a generally T-shaped appearance. A fresh air inlet 91a of the first intake pipe 91 opens toward the right side of the engine 1 (the other left or right side). A fresh air outlet 91b, provided at the other end (downstream side) of the first intake pipe 91 opposite the fresh air inlet 91a, opens toward the left side of the engine 1 (one left or right side). The appearance of the first intake pipe 91 between the fresh air inlet 91a and the fresh air outlet 92b is generally cylindrical and linear.

[0046] A substantially cylindrical connecting portion 91c is integrally formed on the outer peripheral surface of the first intake pipe 91 so as to protrude outward. The connecting portion 91c is provided in a position close to the fresh air outlet 91b in the center of the first intake pipe 91. A blow-by gas inlet 91d at the tip end of the connecting portion 91c is open toward the blow-by gas outlet 67 (rear side of the engine 1). One end of a blow-by gas return pipe 68 is connected to the gas outlet 67, and the other end of the blow-by gas return pipe 68 is connected to the gas outlet 67.

[0047] A fresh air flow outlet 91b of the first intake pipe 91 is connected to a fresh air flow inlet 92a provided at one end of the second intake pipe 92. The second intake pipe 92 is made of, for example, resin, and is generally L-shaped. The fresh air flow outlet 92b provided at the other end of the second intake pipe 92 is connected to an intake inlet 62a of the compressor case 62 of the turbocharger 60. The intake inlet 62a of the compressor case 62 opens toward the cooling fan 9. The second intake pipe 92 is formed so that one end 92a is longer and the other end 92b is shorter than the curved portion.

[0048] In this way, in the engine 1 of this embodiment, the upstream portion of the second intake pipe 92 connected to the intake inlet 62a of the turbocharger 60 and the first intake pipe 91 are piped in the left-right direction and extended to the right side of the engine 1, so that the intake pipes 91, 92 connected to the turbocharger 60 can be laid out compactly without protruding from the front side of the engine 1.

[0049] Incidentally, in the past, when a turbocharger was installed in a small-displacement engine having, for example, three cylinders or less, if a straight intake pipe was attached to the intake-side inlet of the turbocharger, the space between the intake-side inlet of the turbocharger and engine components such as a cooling fan, a fan shroud, and a radiator arranged on one of the front and rear sides of the engine was narrow, making it difficult to attach the intake pipe. With the engine 1 of this embodiment, even if the space between the intake inlet 62a of the turbocharger 60 and engine components such as a cooling fan 9, a fan shroud 20, and a radiator 19 (see FIGS. 3 and 4) arranged on the front side of the engine 1 is narrow, a space can be secured to connect a fresh air piping 99 (see FIG. 17) connected to an air cleaner (not shown) to the first intake pipe 91, and the work of attaching and removing the fresh air piping 99 to the first intake pipe 91 is simplified.

[0050] 15 to 18, the blow-by gas return pipe 68 extends from the blow-by gas outlet 67 toward the front side of the engine 1 and is connected to the connecting portion 91c of the first intake pipe 91, and is inclined upward toward the connecting portion 91c of the first intake pipe 91. This prevents lubricating oil and unburned fuel adhering to the inner wall of the blow-by gas return pipe 68 from flowing into the first intake pipe 91, thereby reducing the mixing of lubricating oil and the like into the combustion air (fresh air) supplied to the engine 1 and the contamination of the intake system path including the compressor case 62 of the turbocharger 60 with lubricating oil and the like. Furthermore, because the upstream portions of the series of intake pipes 91, 92 extend in the left-right direction toward the right side of the engine 1, the blow-by gas return pipe 68 connected to the connecting portion 91c of the first intake pipe 91 can be arranged linearly from the blow-by gas outlet 67 in a plan view, which simplifies the layout of the blow-by gas return pipe 68 and shortens the piping length. By shortening the length of the blow-by gas return pipe 68, it is possible to prevent the blow-by gas return pipe 68 from becoming blocked due to freezing or bending, etc. Furthermore, since the blow-by gas return pipe 68 is disposed directly above the intake manifold 8 integrated with the valve arm chamber, it is possible to prevent the blow-by gas return pipe 68 from becoming blocked due to freezing, etc., by heat dissipation from the engine 1. Furthermore, since most of the blow-by gas return pipe 68 is disposed so as to overlap with the first intake pipe 91 in a front view, and the area of ​​the blow-by gas return pipe 68 exposed to the cooling fan 9 is small, this contributes to preventing the blow-by gas return pipe 68 from freezing due to cooling air.

[0051] As shown in Figures 15 to 17, an intake manifold section 6 having an intake inlet 103 on its upper surface is disposed on the upper surface of the cylinder head 5, and an intake outlet 62b of a turbocharger 60 opens obliquely upward toward the right side of the engine 1. The intake inlet 103 and the intake outlet 62b are connected by an intake relay pipe 66. The intake relay pipe 66 extends obliquely upward from the intake outlet 62b toward the right side of the engine 1, is led above the blow-by gas return pipe 68, and is curved horizontally above the blow-by gas return pipe 68. Furthermore, the intake relay pipe 66 is led above a front portion of the intake manifold section 6 and is curved toward the rear side of the engine 1, is further led above the intake inlet 103, is curved downward, and is connected to the intake inlet 103. As a result, compared to configuration examples in which the intake manifold is disposed on the side of the cylinder head or in which the intake inlet is disposed on the side of the intake manifold, the length of the intake relay pipe 66 can be shortened to reduce intake resistance, and combustion air can be introduced into the engine 1 without impairing the boost pressure obtained by the turbocharger 60. Furthermore, because the intake outlet 62b of the turbocharger 60 and the intake inlet 103 of the intake manifold portion 6 both open upward (diagonally upward), the layout of the intake relay pipe 66 is simplified and the installation work of the intake relay pipe 66 is made easier.

[0052] As shown in Figures 5, 6 and 15 to 17, the intake relay pipe 66 passes above the arm chamber-integrated intake manifold 8 and above the blow-by gas return pipe 68. This allows the intake relay pipe 66 to be located away from the head cover, suppressing a rise in temperature of the combustion air due to heat radiation from the engine 1, while making effective use of the space above the arm chamber-integrated intake manifold 8 to arrange the intake relay pipe 66 and the blow-by gas return pipe 68. In addition, the blow-by gas return pipe 68 can be arranged in a straight line, thereby shortening the piping length of the blow-by gas return pipe 68.

[0053] 16 and 17, the cooling water pump 21 includes a thermostat case 85 that houses a thermostat. A thermostat cover 86 having a cooling water outlet 21b that is connected to a cooling water pipe that leads to the radiator 19 is provided on top of the thermostat case 85. The thermostat cover 86 is disposed below the first intake pipe 91. The thermostat case 85 and the thermostat cover 86 form part of the cooling water pump 21.

[0054] The cooling water pump 21 has a cooling water inlet 21a and a cooling water outlet 21b to which a cooling water feed pipe 87 and a cooling water return pipe 88, which are connected to the radiator 19 (see FIGS. 3 and 4), are connected. The cooling water inlet 21a is provided in the main body of the cooling water pump 21. The cooling water outlet 21b is provided in the thermostat cover 86. The cooling water inlet 21a and the cooling water outlet 21b both open toward the right side of the engine 1.

[0055] 16, the upstream portions of the series of intake pipes 91, 92 are inclined upward from the left side of the engine 1 toward the right side of the engine 1. This allows for a compact configuration in which the height of the turbocharger 60 is kept low without increasing the height of the intake inlet 62a of the turbocharger 60, and therefore the height of the turbocharger 60 itself, while still providing space below the upstream portions of the intake pipes 91, 92 to arrange other components of the engine 1, such as a thermostat cover 86 having a coolant outlet 21b in this embodiment. Furthermore, the space between the fresh air inlet 91a provided in the upstream portions of the intake pipes 91, 92 and the other components arranged below it, such as the thermostat cover 86 in this embodiment, can be made larger, ensuring space for an operator to insert their hands when attaching or detaching a fresh air piping 99 connected to an air cleaner (not shown) to or from the fresh air inlet 91a of the first intake pipe 91, improving ease of operation.

[0056] Furthermore, in the engine 1 of this embodiment, the fresh air inlet 91a of the first intake pipe 91 and the cooling water inlet 21a and cooling water outlet 21b of the cooling water pump 21 are open toward the right side of the engine 1. This allows the installation and maintenance of the fresh air piping 99 connected to the fresh air inlet 91a, the cooling water feed pipe 87 connected to the cooling water inlet 21a, and the cooling water return pipe 88 connected to the cooling water outlet 21b to be performed from the same side of the engine 1 (the right side of the engine 1 in this embodiment), improving the efficiency of these operations.

[0057] 15 and 19, a partition wall 91e is formed inside the first intake pipe 91. The partition wall 91e is formed from the fresh air inlet 91a toward the fresh air outlet 91b, and divides the internal space of the first intake pipe 91 into a fresh air circulation space 91f connecting the fresh air inlet 91a to the fresh air outlet 91b, and a blow-by gas circulation space 91f connecting the blow-by gas inlet 91d to the fresh air outlet 91b. The first intake pipe 91 is separated into a gas flow space 91g. Because of this structure, the first intake pipe 91 is also called a three-way valve. This structure of the first intake pipe 91 prevents the blow-by gas introduced into the first intake pipe 91 from the blow-by gas inlet 91d from flowing back toward the fresh air inlet 91a.

[0058] 15 to 17, in this embodiment, a sensor mounting seat 94 for mounting a temperature sensor 93 is formed in the first intake pipe 91. The temperature sensor 93 is attached to the sensor mounting seat 94, and a sensor portion is inserted into the first intake pipe 91 to measure the temperature of air flowing through the fresh air flow space 91f. The sensor portion of the temperature sensor 93 is disposed in the fresh air flow space 91f separated from the blow-by gas flow space 91g, so that the sensor portion is prevented from being soiled by lubricating oil components contained in the blow-by gas, etc.

[0059] Next, the configuration of exhaust system components and their surroundings will be described with reference to Figures 20 to 23. An exhaust inlet 61a of the turbocharger 60 is connected to an exhaust gas outlet 130 (exhaust-side outlet) provided on the top surface of the exhaust manifold 7. The exhaust manifold 7, which has exhaust gas inlets 131 for three cylinders, is fixed to the left side of the cylinder head 5 with six mounting bolts 132. The exhaust manifold 7 has two bolt insertion holes that sandwich the exhaust gas inlet 131 in the upper and lower directions, one at each periphery of the exhaust gas inlet 131. The bottom side of the exhaust manifold 7 is bifurcated into a front branch portion 133 and a rear branch portion 134 below the exhaust gas outlet 130. The exhaust gas inlet 131 for one cylinder is arranged in the front branch portion 133, and the exhaust gas inlets 131 for two cylinders are arranged in the rear branch portion 134.

[0060] A lubricating oil feed pipe 64 and a lubricating oil return pipe 65 are connected to the center housing 63 of the turbocharger 60. One end of the lubricating oil feed pipe 64 is connected to a lubricating oil feed passage 79 (see Figure 23) inside the cylinder block 4 by a lubricating oil introduction joint 135 at a position near the rear center of the right side of the cylinder block 4. The other end of the lubricating oil feed pipe 64 is connected to the upper part of the center housing 63 by a lubricating oil outlet joint 136.

[0061] The lubricating oil feed pipe 64 is led upward from the lubricating oil inlet joint 135, then bent diagonally upward and rearward, and led to the vicinity of the rear portion of the upper end of the right side of the cylinder block 4. The lubricating oil feed pipe 64 then runs along the upper end of the cylinder block 4 from the right side of the cylinder block 4, over the rear side, and to the left side. A midpoint of the lubricating oil feed pipe 64 is fixed in a position facing the upper end of the rear side of the cylinder block 4 by a pipe locking member 137 bolted to the cylinder head 5. The lubricating oil feed pipe 64 led to the left side of the cylinder block 4 is bent upward behind the exhaust manifold 7, then led to a position higher than the top surface of the cylinder head 5 and bent forward. Furthermore, the lubricating oil feed pipe 64 passes above the rear branch point 134 of the exhaust manifold 7 and is led to a position between the exhaust gas outlet 130 and the left side surface of the intake manifold 8 with integrated valve arm chamber, from where it is led diagonally upward and forward, then bent diagonally upward and left, and further bent approximately horizontally to be connected to a lubricating oil outlet joint 136 attached to the center housing 63 of the turbocharger 60.

[0062] In this way, the lubricant oil feed pipe 64 is routed from the right side surface of the engine 1 to the left side surface thereof, bypassing the rear side surface of the engine 1, and is routed from the rear side of the exhaust manifold 7 on the left side surface of the engine 1, bypassing the outer periphery of the exhaust manifold 7, toward above the exhaust manifold 7, and is compactly arranged along the side surface of the engine 1. Furthermore, because the lubricant oil feed pipe 64 is routed bypassing the outer periphery of the exhaust manifold 7, even when the lubricant oil feed pipe 64 is attached to the engine 1 by the lubricant oil introduction joint 135 and the pipe locking member 137, the lubricant oil feed pipe 64 does not become an obstacle during the installation work of the exhaust manifold 7, and the efficiency of the assembly work of the engine 1 is improved.

[0063] One end of the lubricant return pipe 65 is connected to a pipe flange member 138 bolted to the bottom of the center housing 63, and the other end is connected to a lubricant return joint 140 via an elastic piping member 139 made of, for example, rubber resin. The lubricant return pipe 65 extends downward from the pipe flange member 138, then bends diagonally downward and rearward, and is led to the left side of the exhaust manifold 7 and below the exhaust gas outlet 130. The lubricant return pipe 65 then extends diagonally downward and rightward along the left side of the exhaust manifold 7 toward the branching points of the front branching portion 133 and the rear branching portion 134. Beneath the exhaust manifold 7, the lubricant return pipe 65 bends diagonally forward and diagonally downward and rightward, leading to the vicinity of the left side of the cylinder block 4, and then bends downward and connects to one end of an elastic piping member 139. The elastic piping member 139 is cylindrical and extends vertically. The other end of the elastic piping member 139 is connected to a lubricant return joint 140 located near the front center of the right side of the cylinder block 4. The lubricant return joint 140 is disposed below the center housing 63 as viewed from the left side.

[0064] In the engine 1 of this embodiment, the lubricating oil return pipe 65 that extracts lubricating oil from the turbocharger 60 is routed downward along the bifurcated portion at the bottom of the exhaust manifold 7, so that the lubricating oil return pipe 65 can be routed compactly close to the left side of the engine 1.

[0065] In recent years, market demands for improved fuel economy and lower costs have led to the advancement of more compact engines through the addition of turbochargers, and a significant increase in the number of small-displacement turbocharged engines produced is expected. In contrast, the number of turbocharged small-displacement industrial diesel engines produced has traditionally been small. When a turbocharger is installed on such an engine, the assembly of the turbocharger's peripheral components has traditionally been an extension of that of a naturally aspirated engine, requiring the assembly of the exhaust manifold, turbocharger, and lubricating oil pipe in stages. Therefore, the assembly of the turbocharger's peripheral components has traditionally been carried out in a separate assembly cell for turbocharger-specification engines, which takes time. This conventional assembly method is time-consuming and unable to meet the required production volume.

[0066] In response to such demands, the engine 1 of this embodiment has been improved so that the exhaust manifold 7, turbocharger 60, and lubricant return pipe 65 can be assembled to the engine 1 in an assembled state. As shown in Fig. 20, the component layout of the exhaust manifold 7, turbocharger 60, and lubricant return pipe 65 exposes the mounting bolts 132 when viewed from the left side of the engine 1 so as not to interfere with the attachment of the exhaust manifold 7 to the cylinder head 5. Furthermore, the lubricant return pipe 65 is connected to a lubricant return joint 140 via an elastic piping member 139 so that a single worker can tighten the bolts on the exhaust manifold 7 with the exhaust manifold 7, turbocharger 60, and lubricant return pipe 65 assembled. The worker first connects the lubricant return joint 140 to the cylinder block 4, which allows the lubricant return pipe 65, the elastic piping member 139, and the lubricant return joint 140 to be used as a support during assembly, and also prevents irreversible plastic deformation of the lubricant return pipe 65 due to deformation of the elastic piping member 139.

[0067] This makes it easy for a single worker to assemble the assembled parts consisting of the exhaust manifold 7, turbocharger 60, and lubricant return pipe 65 into the engine 1, and by assembling the exhaust system assembled parts in advance according to the production schedule, it is possible to centralize assembly work and smoothen line work. Furthermore, the increase in assembly man-hours required for a turbocharged engine compared to a naturally aspirated engine can be minimized on the line, making it possible to respond to increased production. Furthermore, by limiting the assembly processes performed in the assembly space dedicated to the turbocharger specification to the installation process of exhaust system parts such as the assembled parts consisting of the exhaust manifold 7, turbocharger 60, and lubricant return pipe 65 and the lubricant feed pipe 64, it is possible to save space in the assembly site.

[0068] The engine device of the present invention is mounted on a work machine such as a lawnmower, a construction machine, an agricultural machine, or an engine generator, for example.

[0069] <Additional Notes> The engine device of the present invention may be an engine device in which a head cover is provided on the top of an engine and a supercharger is provided on one side of the engine, wherein the head cover and the supercharger at least partially overlap in a side view, and at least a portion of an intake pipe connected to an intake side inlet of the supercharger is positioned above the head cover.

[0070] In the above configuration, the intake pipe may have a bent portion, a portion downstream of the bent portion being piped in a front-to-rear direction of the engine and connected to the intake-side inlet of the turbocharger, and a portion upstream of the bent portion being piped in a left-to-right direction of the engine.

[0071] Furthermore, in the above configuration, the upstream portion of the intake pipe may be inclined upward from one left or right side of the engine where the supercharger is provided toward the other left or right side.

[0072] In addition, in the above configuration, a blow-by gas outlet for returning blow-by gas leaking from the combustion chamber to the intake system may be provided in the head cover, and a blow-by gas return pipe may be extended from the blow-by gas outlet in the fore-and-aft direction of the engine, connected to the intake pipe, and inclined upward toward the intake pipe. [Explanation of symbols]

[0073] 1 engine 4 Cylinder block 5. Cylinder head 6 Intake manifold (intake manifold) 7. Exhaust manifold 8. Valve arm chamber integrated intake manifold (head cover) 19 Radiator 20 Fan shroud 21 Cooling water pump 21a Cooling water inlet 21b Cooling water outlet 60 Turbocharger 61a Exhaust inlet (exhaust side inlet) 61b Exhaust outlet 62a Intake inlet (intake side inlet) 62b Intake outlet (intake side outlet) 64 Lubricating oil feed pipe (oil supply pipe) 65 Lubricating oil return pipe (return pipe) 66 Intake relay pipe 67 Blow-by gas outlet 68 Blow-by gas return pipe 69 Blow-by gas reduction device 90 Ben'u Room (Ben'u Room) 91 First intake pipe 91a New air intake 92 Second intake pipe 92b New airflow outlet 101 Bulkhead 130 Exhaust gas outlet (exhaust side outlet) 131 Exhaust gas inlet 139 Elastic piping components

Claims

1. An engine device, a supercharger provided on an exhaust side, which is one of the left and right side surfaces of the engine device; an intake pipe connected to the turbocharger; an intake relay pipe connecting the turbocharger and an intake manifold; Equipped with the intake pipe has a bent portion and extends toward the other of the left and right side surfaces before one end of the engine in the front-rear direction, a first inclined portion that slopes upward from the intake downstream side toward the intake upstream side is provided on the intake upstream side of the bent portion, The intake relay pipe is a second inclined portion that becomes upward from a portion on the upstream side of the airflow flowing through the relay pipe toward a portion on the downstream side; a curved portion leading from the second inclined portion to an intake inlet provided on an upper surface of the intake manifold; An engine device having:

2. The engine apparatus according to claim 1 , wherein at least a portion of the intake relay pipe is provided above the intake pipe.

3. The engine apparatus according to claim 2 , wherein the intake inlet of the intake pipe is provided below a top of the intake relay pipe.

4. 4. The engine apparatus according to claim 2, wherein the intake inlet of the intake pipe is provided above the intake inlet of the intake manifold.

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