engine

Abstract

To suppress damage to a support mechanism of a DPF due to oscillation by rational modification utilizing the arrangement configuration of a cylinder head.SOLUTION: An engine comprises: a cylinder head; an exhaust manifold; an exhaust gas purification device that purifies exhaust gas from the exhaust manifold; and a support mechanism that fixes the exhaust gas purification device to at least the cylinder head. The exhaust gas purification device is arranged perpendicular to a longitudinal direction of the engine, and the support mechanism has a support member that fixes the exhaust gas purification device at least in vertical and horizontal directions of the engine.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to an engine such as a diesel engine mounted on a work machine such as a construction machine or an agricultural machine. [Background technology]

[0002] Conventionally, there is known an engine in which a DPF that purifies exhaust gas from an exhaust manifold is disposed above a cylinder head in an orientation perpendicular or nearly perpendicular to the rotational axis of the crankshaft in a plan view, and an intake collector that recirculates a portion of the exhaust gas to the intake manifold as EGR gas is fixed to the intake manifold. In the above-mentioned engine, the orientation of the DPF disposed above the cylinder head is configured to be horizontal, perpendicular or nearly perpendicular to the rotational axis of the crankshaft in a plan view, so that the occupied space around the engine can be made more compact than when, for example, the DPF is disposed along the rotational axis of the crankshaft.

[0003] To support the above-described horizontally oriented DPF on the engine, a conventional support mechanism is provided to support the DPF on the cylinder head and intake manifold, as shown in Patent Document 1. This support mechanism is composed of an inlet bracket for fixing the exhaust manifold-side portion of the DPF to the left side of the cylinder head, an outlet bracket for fixing the intake manifold-side portion of the DPF to the front surface of the cylinder head, and a connecting bracket for connecting the upper and lower intermediate portions of the outlet bracket to the intake manifold. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-178813 Summary of the Invention [Problem to be solved by the invention]

[0005] In the DPF support structure described above, the inlet bracket is attached to the left side of the cylinder head, the outlet bracket is attached to the front of the cylinder head, and the connecting bracket is attached to the intake manifold, all of which are located close to each other along a line perpendicular to the crankshaft axis in a plan view. This means that the DPF is prone to swinging in the pitch direction (direction b in Figure 1) along the crankshaft axis due to vibrations transmitted to the engine. In particular, in the case of engines mounted on work machines such as skid steer loaders, a large-mass driven device such as a hydraulic pump for the work machine (shown by phantom lines in Figures 1 and 2) is fixedly connected to a flywheel housing facing the output shaft for the driven device. Therefore, when the work machine travels over uneven ground or steps, the up-and-down vibration of the work machine (indicated by arrow a in Figure 1) is amplified by the large-mass driven device and propagated to the engine and DPF as vibration in the pitch direction (indicated by arrow b in Figure 1). At this time, because the DPF is located on the end of the upper part of the cylinder head, away from the output shaft for the driven device, the DPF vibrates more in the pitch direction than the engine, which may cause damage to the DPF support mechanism.

[0006] In view of this situation, a main object of the present invention is to provide an engine that can suppress damage to the DPF support mechanism due to vibrations by rationally modifying the cylinder head arrangement. [Means for solving the problem]

[0007] A first characteristic configuration of the present invention is an engine comprising a cylinder head, an exhaust manifold, an exhaust gas purification device that purifies exhaust gas from the exhaust manifold, and a support mechanism that fixes the exhaust gas purification device to at least the cylinder head, wherein the exhaust gas purification device is arranged perpendicular to the longitudinal direction of the engine, and the support mechanism has support members that fix the exhaust gas purification device at least in the vertical and horizontal directions of the engine.

[0008] A second characteristic feature of the present invention is that the exhaust gas purification device is further fixed in the left-right direction of the engine by the support mechanism.

[0009] A third characteristic feature of the present invention is that the exhaust gas purification device is provided with its longitudinal direction facing the left-right direction of the engine.

[0010] A fourth characteristic feature of the present invention is that the support member is attached to the cylinder head and the intake manifold. A fifth characteristic feature of the present invention is that a support base that supports the exhaust manifold side of the exhaust gas purification device is fixed to the cylinder head. [Brief explanation of the drawings]

[0011] [Figure 1] Left perspective view of diesel engine [Figure 2] Right perspective view of a diesel engine [Figure 3] Perspective view of the top of the engine with the DPF separated [Figure 4] Left perspective view of the DPF mounting area [Figure 5] Right-side perspective view of the DPF mounting area [Figure 6] Front perspective view of the DPF mounting area [Figure 7] Exploded perspective view of the DPF mounting section [Figure 8] Perspective view of the DPF mounting assembly DETAILED DESCRIPTION OF THE INVENTION

[0012] An embodiment of the present invention will be described with reference to the drawings. 1 and 2 show an example of an engine, a diesel engine 1, as a prime mover mounted on a work machine such as a construction machine or an agricultural machine. For convenience in describing the diesel engine 1, the side where the exhaust manifold 7 is located will be referred to as the left side of the diesel engine 1, and the side where the intake manifold 6 is located will be referred to as the right side of the diesel engine 1. Furthermore, the direction of the rotational axis of the crankshaft (engine output shaft) 2 will be referred to as the front-to-rear direction, with the side where a cooling fan (not shown) is located being referred to as the front side, and the side of the output shaft portion 2A of the crankshaft 2 relative to the driven device 100 being referred to as the rear side. 1 and 2 are perspective views of the entire diesel engine 1. In order to clearly show the support structure of the DPF 40, Figures 3 to 8 show the engine in a state where peripheral parts are appropriately removed. For example, Figure 6 shows the engine in a state where the turbocharger 30 is removed.

[0013] As shown in Figures 1 and 2, a diesel engine 1 includes a cylinder block 3 that houses a crankshaft 2 and pistons (not shown) for engine output. A cylinder head 4 is fixed to the top surface of the cylinder block 3, and a head cover 5 is fixed to the top surface of the cylinder head 4. An intake manifold 6 is fixed to the right side surface 4c (see Figure 7) of the cylinder head 4, and an exhaust manifold 7 is fixed to the left side surface 4b (see Figure 7) of the cylinder head 4. A fan shaft 8 that supports a cooling fan (not shown) is provided on the front surface of the cylinder block 3. A flywheel housing 9 is fixed to the rear surface of the cylinder block 3, and a flywheel 10 that is supported on the output shaft portion 2A on the rear end side of the crankshaft 2 is disposed within this flywheel housing 9.

[0014] In this embodiment, as shown by the phantom lines in Figures 1 and 2, a driven device 100 with a large mass, such as a hydraulic pump for a work machine, is fixedly connected to the flywheel housing 9 and is directly connected to the output shaft portion 2A of the crankshaft 2.

[0015] The intake system of the diesel engine 1 includes an intake pipe 15 in which a compressor 32 of a turbocharger 30 (described later) is provided, an intake collector 51 of an EGR device 50 (described later), and an intake manifold 6.

[0016] As shown in FIG. 1, the turbocharger 30 is composed of a turbine 31 of the turbocharger 30 provided in the exhaust pipe 20 and a compressor 32 provided in the intake pipe 15. The turbine 31 rotates using the energy of the exhaust gas flowing through the exhaust pipe 20, driving the compressor 32 which is coaxial with the turbine 31. The compressor 32 compresses fresh air (external air) taken in via an air cleaner (not shown). The "fresh air" refers to air that does not contain EGR gas, which will be described later. The compressed air, which exceeds atmospheric pressure, is sent to an intake air collector 51.

[0017] As shown in Fig. 6, an exhaust gas discharge tube section 21 that opens outward and upward is integrally formed with the exhaust manifold 7. As shown in Fig. 1, a gas inlet section of a turbine 31 is connected to this exhaust gas discharge tube section 21, and an upstream end of an elbow-shaped pipe joint 22 is connected to a gas outlet section of the turbine 31. An upstream end of an exhaust connecting pipe 23 that is connected to an exhaust gas introduction section 42 of the DPF 40 is connected to a downstream end of the elbow-shaped pipe joint 22. A downstream connecting flange 23A of the exhaust connecting pipe 23 is bolted to a connecting flange 42A of the exhaust gas introduction section 42 of the DPF 40, as shown in Figs. 1 and 2. The pipe joint 22 and the exhaust connecting pipe 23 described above constitute the exhaust pipe 20.

[0018] As shown in Figure 2, the intake manifold 6 divides the compressed air supplied via the intake pipe 15 into a number of portions corresponding to the number of cylinders and supplies them to the cylinder head 4. Injectors (fuel injection devices) 16 are arranged in the cylinder head 4. The injectors 16 inject fuel into the combustion chambers at predetermined timing. The injectors 16 inject fuel to drive pistons in the cylinder block 3, allowing the diesel engine 1 to generate power.

[0019] As shown in FIG. 1, the exhaust system of the diesel engine 1 includes an exhaust manifold 7, an exhaust pipe 20 in which a turbine 31 of a turbocharger 30 is provided, and a DPF 40 that constitutes a continuous regeneration type exhaust gas purification device.

[0020] The exhaust manifold 7 collects exhaust gases generated in multiple combustion chambers and supplies them to the turbine 31 of the turbocharger 30. A portion of the exhaust gas that passes through the exhaust manifold 7 is recirculated to the intake system as EGR gas by the EGR device 50, and the remainder is purified by the DPF 40 and then discharged.

[0021] 1 and 2, the EGR device 50 includes an intake collector 51 that mixes a portion of the EGR gas from the exhaust manifold 7 with fresh air supplied from the intake pipe 15 and supplies the mixture to the intake manifold 6, an intake throttle member 52 that connects the intake pipe 15 to the intake collector 51, a recirculation exhaust gas pipe 54 as a reflux line connected to the exhaust manifold 7 via an EGR cooler 53, and an EGR valve member 55 that connects the intake collector 51 to the recirculation exhaust gas pipe 54. The amount of EGR gas supplied to the intake collector 51 is adjusted by adjusting the opening of an EGR valve (not shown) in the EGR valve member 55.

[0022] With the above-described configuration, fresh air (external air) is supplied from the intake pipe 15 into the intake collector 51 via the intake throttle member 52, while EGR gas is supplied from the exhaust manifold 7 into the intake collector 51 via the EGR valve member 55. The fresh air from the intake pipe 15 and the EGR gas from the exhaust manifold 7 are mixed in the intake collector 51 and then supplied to the intake manifold 6. That is, by returning a portion of the exhaust gas discharged from the diesel engine 1 to the exhaust manifold 7 from the intake manifold 6 to the diesel engine 1, the maximum combustion temperature during high load operation is lowered and the amount of NOx (nitrogen oxides) emitted from the diesel engine 1 is reduced.

[0023] A gas inlet of the EGR cooler 53 is connected to an EGR gas extraction pipe 56 formed integrally with the exhaust manifold 7, and a gas outlet of the EGR cooler 53 is connected to a recirculation exhaust gas pipe 54 via a pipe joint member 57. The pipe joint member 57 is fastened to the exhaust manifold 7 with bolts.

[0024] The DPF 40 includes an exhaust gas purification case 41 made of a heat-resistant metal material and having a cylindrical shape extending in the left-right direction. An exhaust gas inlet 42 having an exhaust gas inlet port 42a (see FIG. 3) that opens rearward is formed on the left end side of the outer peripheral surface of the exhaust gas purification case 41. A purified gas outlet 43 that discharges purified exhaust gas is provided on the right end surface of the exhaust gas purification case 41. The exhaust gas discharged from the purified gas outlet 43 is discharged to the outside via a silencer or a tailpipe.

[0025] 3, the exhaust gas purification case 41 includes a catalyst case body 45 having a platinum or other diesel oxidation catalyst 44 (gas purifier) ​​mounted therein that generates nitrogen dioxide (NO2), and a filter case body 47 having a honeycomb structure soot filter 46 (gas purifier) ​​mounted therein that continuously oxidizes and removes trapped particulate matter (PM) at a relatively low temperature. A first connecting flange 45A provided at the gas outlet end of the catalyst case body 45 and a second connecting flange 47A provided at the gas inlet end of the filter case body 47 are joined from the left and right directions and fastened together with bolts and nuts.

[0026] 2 and 3, a cover 48 having a purified gas discharge port 43 and a third connecting flange 49 are provided at the gas outlet end of the filter case body 47. Segmented reinforcing flange plates 50A and 50B (see FIG. 1), which are circumferentially divided into two, are fastened to the back surface of the third connecting flange 49 with bolts and nuts. A connecting plate portion 50a that protrudes radially outward beyond the third connecting flange 49 is integrally formed with the lower segmented reinforcing flange plate 50A. A plurality of bolt insertion holes 50b are formed in this connecting plate portion 50a for fastening a first bracket 70 (described below) from the left and right with first bolts 74 and nuts 75. 3, in this embodiment, the bolt insertion holes 50b are formed at three locations in the circumferential direction on the lower side of the split reinforcing flange plate 50A on the exhaust gas purification case 41 side. The bolt insertion holes 50b located on both sides in the circumferential direction are formed as circular holes, and the bolt insertion hole 50b located in the circumferential center is formed as a notched hole that is generally U-shaped and opens downward.

[0027] With the above-described configuration, nitrogen dioxide (NO2) generated by the oxidation action of the diesel oxidation catalyst 44 is supplied into the soot filter 46. Particulate matter (PM) contained in the exhaust gas of the diesel engine 1 is trapped in the soot filter 46 and continuously oxidized and removed by the nitrogen dioxide (NO2). In addition to removing particulate matter (PM) from the exhaust gas of the diesel engine 1, the contents of carbon monoxide (CO) and hydrocarbons (HC) in the exhaust gas of the diesel engine 1 are reduced.

[0028] In the case of a diesel engine 1 configured as described above, particularly a diesel engine 1 mounted on a work machine such as a skid steer loader, a large-mass driven device 100, such as a hydraulic pump for the work machine, is fixedly connected to the output shaft 2A of the crankshaft 2, as shown by the phantom lines in FIGS. 1 and 2. Therefore, when the work machine travels over uneven ground or steps, the up-and-down vibration of the work machine (indicated by the arrow a in FIG. 1 ) is amplified by the large-mass driven device 100 and propagated to the diesel engine 1 and the DPF 40 as vibration in the pitch direction (indicated by the arrow b in FIG. 1 ). At this time, since the DPF 40 is disposed on the front end side of the upper part of the cylinder head 4, which is spaced forward from the output shaft 2A side of the crankshaft 2, a phenomenon occurs in which the DPF 40 vibrates more in the pitch direction than the diesel engine 1.

[0029] Therefore, the support structure of the DPF 40 of the present invention is a rational modification that utilizes the arrangement of the intake side of the cylinder head 4 to take measures against the vibration in the pitch direction as described above, and the specific structure will be described in detail below. 3 to 8, a support mechanism 60 is provided that supports the exhaust gas purification case 41 of the DPF 40 on the cylinder head 4 and the intake manifold 6, and also on the intake collector 51 that is displaced in the direction of the rotational axis of the crankshaft 2 from the support position. This support mechanism 60 is made up of a first support 61 that supports the exhaust gas purification case 41 on the cylinder head 4 and the intake manifold 6, and a second support 62 that supports the exhaust gas purification case 41 on the intake collector 51. Furthermore, the first support 61 is composed of a first bracket 70 that fixes the portion of the exhaust gas purification case 41 on the intake manifold 6 side to the cylinder head 4 and the intake manifold 6, and a fixing band 90 that fixes the portion of the exhaust gas purification case 41 on the exhaust manifold 7 side to the cylinder head 4. The second support 62 is composed of a second bracket 80 that spans between the first bracket 70 and the intake collector 51.

[0030] As shown in Figures 5 to 7, the first bracket 70 comprises a first mounting plate portion 71 in a vertical position along the front-to-rear direction so as to be able to abut against the back surface of the divided reinforcing flange plate 50A of the exhaust gas purification case 41, a second mounting plate portion 72 in a vertical position along the left-to-right direction so as to be able to abut against the front surface 4a of the cylinder head 4, and a third mounting plate portion 73 in a horizontal position along the left-to-right direction so as to be able to abut against the first mounting portion 65 formed on the upper surface of the front end portion of the intake manifold 6. The second mounting plate portion 72 is formed by bending the front end of the first mounting plate portion 71 at a right angle inward in the left-right direction, and extends diagonally downward toward the left side of the front surface 4a of the cylinder head 4. The third mounting plate portion 73 is formed by bending the lower end of the first mounting plate portion 71 at a right angle inward in the left-right direction along the horizontal direction.

[0031] As shown in Figures 5 to 7, a plurality of first bolt insertion holes 71a are formed in the upper end of the first mounting plate portion 71 of the first bracket 70 for fastening the connecting plate portion 50a of the divided reinforcing flange plate 50A of the exhaust gas purification case 41 with first bolts 74 and nuts 75 in a left-right orientation. In this embodiment, the first bolt insertion holes 71a of the first mounting plate portion 71 are formed at positions corresponding to three circumferential locations of the divided reinforcing flange plate 50A of the exhaust gas purification case 41. The first bolt 74 inserted into the first bolt insertion hole 71a at the circumferential center is inserted from the inner side, opposite to the first bolts 74 inserted into the first bolt insertion holes 71a on both circumferential sides, and a nut 75 is screwed on from the outer side. This is so that, with the exhaust gas purification case 41 of the DPF 40 placed on the receiving surface 91a of the support base 91 of the fixing band 90, the substantially "U"-shaped bolt insertion hole 50b on the circumferential center side of the lower divided reinforcing flange plate 50A is engaged and held from above with the first bolt 74 at the circumferential center. As a result, the weight of the DPF 40 is placed and supported by the first bracket 70 and the support base 91 of the fixing band 90, making it easy to fix the DPF 40.

[0032] As shown in Figures 5 to 7, the lower end of the second mounting plate portion 72 is formed with a plurality of second bolt insertion holes 72a for fastening with second bolts 76 in a longitudinal direction to a plurality of screw holes (not shown) formed in the right side portion of the front surface 4a of the cylinder head 4. In this embodiment, the second bolt insertion holes 72a of the second attachment plate portion 72 are formed at three locations that become the vertices of a triangle.

[0033] As shown in Figures 4, 7, and 8, a plurality of third bolt insertion holes 73a are formed at the tip of the third mounting plate portion 73 for fastening with third bolts 77 in an up-down position to a plurality of first screw holes 65a formed in the first mounting portion 65 of the intake manifold 6. In this embodiment, the third bolt insertion holes 73a of the third attachment plate portion 73 are formed at two locations spaced a predetermined distance apart in the front-rear direction. As shown in FIG. 7, the first mounting portion 65 of the intake manifold 6 is configured in a form in which two pillar-shaped bodies 65A are integrally joined in the front-to-rear direction, and first screw holes 65a that open upward are formed in the horizontal upper surfaces of both pillar-shaped bodies 65A.

[0034] 7 and 8, a horizontal reinforcing plate 78 spanning the inner surface of the first mounting plate portion 71 and the inner surface of the second mounting plate portion 72 of the first bracket 70 is fixed by welding or the like. A load transfer plate 79, which abuts against the upper surface of the reinforcing plate 78 from above, is fixed to the inner surface of the first mounting plate portion 71 of the first bracket 70 together with the divided reinforcing flange plate 50A of the exhaust gas purification case 41 by first bolts 74 and nuts 75. Therefore, fourth bolt insertion holes 79a penetrating in the left-right direction are formed in each of three locations on the load transfer plate 79 along the circumferential direction of the divided reinforcing flange plate 50A. As shown in FIG. 7, nuts 75 are fixed by welding or the like to the inner surface of the load transfer plate 79 at locations corresponding to the fourth bolt insertion holes 79a on both circumferential sides.

[0035] With the above-described configuration, part of the load of the DPF 40 can also be supported at the contact portion between the reinforcing plate 78 of the first bracket 70 and the load transmission plate 79. Therefore, the support mechanism 60 for the DPF 40 can be made stronger than when the first mounting plate portion 71 of the first bracket 70 and the split reinforcing flange plate 50A on the exhaust gas purification case 41 side are fastened only with the first bolts 74 and nuts 75.

[0036] As shown in Figures 4, 7 and 8, the second bracket 80 comprises a vertical plate portion 81 extending in the fore-and-aft direction that can abut against the inner surface of the first mounting plate portion 71 of the first bracket 70, excluding the mounting areas of the reinforcing plate 78 and the load transfer plate 79, and a horizontal plate portion (an example of a contact portion) 82 extending in the fore-and-aft direction that can abut from above against the horizontal upper surface of the second mounting portion 66 that is formed to protrude from the upper surface of the front end of the intake collector 51. The vertical plate portion 81 is formed with an outline shape that is roughly "L" shaped when viewed from the left and right, and the horizontal plate portion 82 is formed by bending the lower end of the vertical plate portion 81 at a right angle toward the inside in the left and right direction.

[0037] 7, a third screw hole 81a penetrating in the left-right direction is formed in each of the upper end and front end of the vertical plate portion 81 of the second bracket 80. A fifth bolt insertion hole 71b penetrating in the left-right direction is also formed in the first mounting plate portion 71 of the first bracket 70 corresponding to the third screw hole 81a in the vertical plate portion 81. As shown in Figures 3 to 5 and 7, the vertical plate portion 81 of the second bracket 80 and the first mounting plate portion 71 of the first bracket 70 are fastened together by threading a fourth bolt 83 in a left-right orientation that is inserted into the fifth bolt insertion hole 71b into the third screw hole 81a.

[0038] As shown in Figure 7, a sixth bolt insertion hole 82a that penetrates in the vertical direction is formed in the horizontal plate portion 82 of the second bracket 80, and a second screw hole 66a that opens upward is formed in the second mounting portion 66 of the intake collector 51. In this embodiment, the sixth bolt insertion hole 82a of the horizontal plate portion 82 and the second screw hole 66a of the second mounting portion 66 are formed at two locations in the front-to-rear direction. In addition, the sixth bolt insertion hole 82a of the horizontal plate portion 82 is formed as a substantially U-shaped notch that opens toward the intake manifold 6 side in a plan view. The horizontal plate portion 82 of the second bracket 80 and the second mounting portion 66 of the intake collector 51 are fastened together by threading a fifth bolt 84 in an up-down position, which is inserted into the sixth bolt insertion hole 82a of the horizontal plate portion 82, into the second screw hole 66a of the second mounting portion 66.

[0039] As shown in Figures 3 and 5 to 8, the fixing band 90 comprises a support base 91 that is approximately Y-shaped when viewed from the left and right and has an arc-shaped receiving surface 91a that can receive the portion of the exhaust gas purification case 41 on the exhaust manifold 7 side, and a flexible band member 92 that pulls the exhaust gas purification case 41 placed on the support base 91 toward the receiving surface 91a and tightens and fixes it. As shown in FIG. 7, a plurality of seventh bolt insertion holes 95 are formed at the lower end of the support base 91 for fastening sixth bolts 94 in a left-right orientation to a plurality of fourth screw holes 93 formed in the front end portion of the left side surface 4b of the cylinder head 4.

[0040] 5 to 8, a first screw insertion hole 97 is formed through the rear end of the receiving surface 91a of the support base 91, into which is inserted a screw shaft 96a of a first fixing bracket 96 provided at one end of the band member 92. The screw shaft 96a of the first fixing bracket 96 inserted into this first screw insertion hole 97 is secured by screwing a nut 96b onto the tip end of the screw shaft 96a protruding downward from the first screw insertion hole 97 (see FIG. 8). 3, 7, and 8, a second screw insertion hole 99 (see FIG. 8) having a generally U-shape in plan view is cut out at the front end of the receiving surface 91a of the support base 91, and the screw shaft 98a of the second fixing bracket 98 provided at the other end of the band member 92 can be attached and detached from the front side. A nut 98b is screwed onto the tip end of the screw shaft 98a of the second fixing bracket 98 inserted into the second screw insertion hole 99, and the nut 98b is tightened. The diameter of the band member 92 is reduced as the nut 98b is tightened, and the exhaust gas purification case 41 placed on the support base 91 is pulled toward the receiving surface 91a, where it is tightened and fixed.

[0041] In the support structure for the DPF 40 configured as described above, as shown in Figures 7 and 8, the intake manifold 6 is firmly fixed with multiple bolts to the right side surface 4c of the cylinder head 4. Furthermore, the intake collector 51 is firmly fixed with multiple bolts to the outer surface of the intake manifold 6. Therefore, the cylinder head 4, the intake manifold 6, and the intake collector 51 belong to the same vibration system.

[0042] As shown in Figures 7 and 8, the intake manifold 6 has a length that extends from near the front end of the right side surface 4c of the cylinder head 4 to near the rear end. The intake collector 51 has a length that extends from a position slightly offset rearward from the front end of the intake manifold 6 to near the rear end of the intake manifold 6. Therefore, as shown in Figures 4 and 8, a first mounting portion 65 formed on the upper surface of the front end of the intake manifold 6 is located slightly rearward of the front surface 4a of the cylinder head 4. A second mounting portion 66 formed to protrude from the upper surface of the front end of the intake collector 51 is positioned slightly rearward of the first mounting portion 65 of the intake manifold 6.

[0043] 5 and 6, a second mounting plate portion 72 of a first bracket 70 constituting one of the first supports 61 of the support mechanism 60 is firmly fixed to the front surface 4a of the cylinder head 4 by a plurality of second bolts 76 oriented in the front-rear direction. The fixed connection position between the second mounting plate portion 72 of the first bracket 70 and the front surface 4a of the cylinder head 4 becomes a first support position P1 where the DPF 40 is supported by the cylinder head 4. 4, 5, and 8, the third mounting plate 73 of the first bracket 70 abuts from above against the first mounting portion 65 of the intake manifold 6, which is offset slightly rearward from the front surface 4a of the cylinder head 4, and this abutting third mounting plate 73 is firmly fixed to the first mounting portion 65 of the intake manifold 6 with a plurality of third bolts 77 oriented in the vertical direction. The fixed connection position between the first mounting portion 65 of the intake manifold 6 and the third mounting plate 73 of the first bracket 70 becomes the second support position P2 where the DPF 40 is supported by the intake manifold 6.

[0044] 4, 5, and 8, the vertical plate portion 81 of the second bracket 80 of the second support 62 is firmly fixed to the first mounting plate portion 71 of the first bracket 70 with a plurality of fourth bolts 83 oriented in the left-right direction. The horizontal plate portion 82 of this second bracket 80 abuts from above against the second mounting portion 66 of the intake air collector 51, which is offset rearward from the first mounting portion 65 of the intake manifold 6, and this abutting horizontal plate portion 82 is firmly fixed to the second mounting portion 66 of the intake air collector 51 with a plurality of fifth bolts 84 oriented in the up-down direction. The fixed connection position between the horizontal plate portion 82 of the second bracket 80 and the second mounting portion 66 of the intake air collector 51 becomes a third support position P3 where the DPF 40 is supported by the intake air collector 51.

[0045] The divided reinforcing flange plate 50A of the exhaust gas purification case 41 of the DPF 40 is firmly connected to the first mounting plate portion 71 of the first bracket 70 with a plurality of first bolts 74 and nuts 75. In this connected state, the portion of the DPF 40 on the intake manifold 6 side is supported at three points offset in the front-rear direction: a first support position P1 on the front surface 4a of the cylinder head 4; a second support position P2 on the first mounting portion 65 of the intake manifold 6; and a third support position P3 on the second mounting portion 66 of the intake collector 51. This improves the support strength against vibration in the pitch direction along the rotational axis of the crankshaft 2. Furthermore, compared to when the support mechanism 60 for the DPF 40 is fixed between different members of a vibration system, internal stress in the support mechanism 60 can be suppressed, resulting in a robust support mechanism 60. Therefore, the above-described rational modification using the intake collector 51, which is an arrangement on the intake side of the cylinder head 4, can prevent damage to the support mechanism 60 of the DPF 40 due to vibration in the pitch direction.

[0046] Furthermore, the first bracket 70 of the first support 61 is provided at a portion of the DPF 40 on the intake manifold 6 side, that is, between the divided reinforcing flange plate 50A of the exhaust gas purification case 41, the front surface 4a of the cylinder head 4, and the first mounting portion 65 of the intake manifold 6, so the installation distance between this first bracket 70 and the second mounting portion 66 of the intake collector 51 is shorter than the distance between the DPF 40 and the intake collector 51. The shorter installation distance allows for a reduction in weight and cost of the second bracket 80 that constitutes the second support 62.

[0047] Furthermore, compared to when the second bracket 80 of the second support 62 is supported by the cylinder head 4 or the intake manifold 6, the rigidity of the cylinder head 4 and the intake manifold 6 can be ensured by distributing the load to the intake collector 51.

[0048] Other Embodiments (1) In the above embodiment, the diesel engine 1 is described in which the DPF 40 is disposed at an end portion of the upper part of the cylinder head 4 away from the output shaft portion 2A for the driven device 100. However, the technology of the present invention can also be applied to a diesel engine 1 in which the DPF 40 is disposed at an end portion of the upper part of the cylinder head 4 closer to the output shaft portion 2A.

[0049] (2) In the above-described embodiment, the first bracket 70 of the first support 61 and the second bracket 80 of the second support 62 are constructed separately, but the first bracket 70 and the second bracket 80 may be constructed integrally by bending, welding, or the like.

[0050] (3) In the above-described embodiment, the second bracket 80 of the second support 62 is installed across the first bracket 70 and the second mounting portion 66 of the intake collector 51, but this second bracket 80 may also be installed across the DPF 40 and the second mounting portion 66 of the intake collector 51.

[0051] [Note] As described above, the engine according to an embodiment of the present invention is an engine in which a DPF that purifies exhaust gas from the exhaust manifold is arranged above the cylinder head, and may be configured to be provided with a support mechanism that supports the DPF at least on the cylinder head and the intake manifold.

[0052] In the above configuration, a support base that supports the exhaust manifold side of the DPF may be fixed to the cylinder head.

[0053] In the above configuration, an intake collector that recirculates a portion of the exhaust gas to the intake manifold as EGR gas may be fixed to the intake manifold, and a support mechanism may be provided that supports the DPF on the cylinder head, the intake manifold, and the intake collector.

[0054] In the above configuration, the support mechanism may include at least a first support that supports the DPF on the cylinder head and the intake manifold, and a second support that supports the DPF on the intake collector.

[0055] In the above configuration, the support mechanism may be provided with a first support position for supporting the DPF on the cylinder head, a second support position for supporting the DPF on the intake manifold, and a third support position for supporting the DPF on the intake collector, and the third support position may be disposed at a position offset in the direction of the rotational axis of the crankshaft from the first support position and the second support position.

[0056] With the above-described configuration, the DPF can be supported by a support mechanism that is supported by the cylinder head and intake manifold, which share the same vibration system, thereby improving support strength against vibration. Moreover, compared to when the DPF support mechanism is fixed between components with different vibration systems, the generation of internal stress in the support mechanism can be suppressed, resulting in a more robust support mechanism. [Explanation of symbols]

[0057] 2 crankshaft 2A output shaft 4. Cylinder head 6. Intake manifold 7. Exhaust manifold 40 DPF 51 Intake collector 60 Support mechanism 61 1st support 62 Second support 66 Mounting part (second mounting part) 70 First Bracket 80 Second Bracket 82 Contact part (horizontal plate part) 84 Volts (5th Volt) 100 Driven equipment P1 1st support position P2 2nd support position P3 3rd support position

Claims

1. A cylinder head, An exhaust manifold, an exhaust gas purification device that purifies exhaust gas from the exhaust manifold; a support mechanism for fixing the exhaust gas purification device to at least the cylinder head, the exhaust gas purification device is disposed perpendicular to the longitudinal direction of the engine, The support mechanism has a support member that fixes the exhaust gas purification device at least in the vertical and horizontal directions of the engine.

2. 2. The engine of claim 1, The exhaust gas purification device is further fixed in the left-right direction of the engine by the support mechanism.

3. 3. The engine according to claim 1 or 2, The exhaust gas purification device is provided so that its longitudinal direction faces the left-right direction of the engine.

4. An engine according to any one of claims 1 to 3, The support member is attached to the cylinder head and the intake manifold.

5. An engine according to any one of claims 1 to 4, A support base for supporting the exhaust manifold side of the exhaust gas purification device is fixed to the cylinder head.

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