engine

Abstract

To provide a technology suitable for an engine with a structure of which total width is likely to relatively becomes large relative to the total length thereof.SOLUTION: An engine includes: a coolant cooler for cooling a first coolant for cooling an engine block constituted of a cylinder block and a cylinder head; and a lubricant cooler for cooling a lubricant using the first coolant or a second coolant. The coolant cooler and the lubricant cooler are disposed while being aligned on one end side in a crankshaft direction.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to an engine. [Background technology]

[0002] Patent Document 1 discloses a technique for making an engine more compact by reducing the overall height, overall length, and overall width of the engine.

[0003] The turbocharged engine disclosed in Patent Document 1 includes a fresh water cooler that cools the fresh water cooling water supplied to the inside of the engine, and a lubricant oil cooler that cools the lubricant oil. The fresh water cooler is disposed on the surface of the cylinder head opposite the output side of the engine, and the lubricant oil cooler is disposed substantially directly below the exhaust manifold so that its longitudinal direction is parallel to the longitudinal direction of the exhaust manifold. In other words, the lubricant oil cooler is disposed on the side of the engine. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2005-299393 A Summary of the Invention [Problem to be solved by the invention]

[0005] The configuration of Patent Document 1 is effective when the overall width of the engine is relatively small compared to the overall length, such as in an in-line multi-cylinder engine. However, because the lubricant oil cooler is disposed on the side of the engine, there is a concern that the overall width of the engine will become too large when the configuration of Patent Document 1 is applied, when the overall width of the engine is relatively large compared to the overall length, such as in a V-type engine.

[0006] An object of the present invention is to provide a technique suitable for engines whose structure tends to make the overall width relatively large relative to the overall length. [Means for solving the problem]

[0007] An exemplary engine of the present invention includes a coolant cooler that cools a first coolant that cools an engine block composed of a cylinder block and a cylinder head, and a lubricant oil cooler that cools a lubricant oil by using the first coolant or the second coolant. The coolant cooler and the lubricant oil cooler are arranged side by side on one end side in the crankshaft direction. Effect of the Invention

[0008] According to the exemplary embodiment of the present invention, it is possible to provide a technology suitable for engines having a structure in which the overall width is likely to be relatively large relative to the overall length. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic perspective view showing the configuration of an engine. [Diagram 2] FIG. 2 is a schematic perspective view showing a portion of the engine that is composed of a cylinder block, a head block, and a head cover. [Diagram 3] Schematic cross-sectional view of a cylinder block portion of an engine. [Figure 4] Schematic top view showing the engine configuration [Diagram 5] FIG. 2 is a diagram showing a schematic configuration of a coolant flow path provided in the engine; [Figure 6] Schematic front view showing the engine configuration [Figure 7] FIG. 2 is a schematic perspective view showing components that form a part of the cooling liquid flow path dedicated to the right cylinder bank and the left cylinder bank; [Figure 8] FIG. 8 is a schematic cross-sectional perspective view showing a cross section taken along the line VIII-VIII shown in FIG. 7 . [Figure 9] FIG. 2 is a schematic perspective view showing the configuration of a right exhaust pipe provided in the engine. [Figure 10] FIG. 2 is a schematic perspective view showing the configuration of a gear case provided in the engine; [Figure 11] FIG. 11 is a schematic perspective view of the gear case when the gear case is viewed from a different direction from that shown in FIG. [Figure 12]FIG. 1 is a schematic right side view showing the configuration of a gear case provided in an engine. [Figure 13] FIG. 13 is a schematic cross-sectional perspective view showing a cross section taken along the line XIII-XIII shown in FIG. 12 . [Figure 14] FIG. 14 is a schematic cross-sectional perspective view showing a cross section taken along the line XIV-XIV shown in FIG. 12 . [Figure 15] FIG. 2 is a schematic perspective view showing a mounting structure of a coolant cooler and a lubricant oil cooler provided in an engine; [Figure 16] FIG. 2 is a schematic perspective view showing a configuration of a heat exchanger provided in the coolant cooler; [Figure 17] FIG. 1 is a schematic diagram for explaining the configuration of a heat exchanger of a cooling liquid cooler; [Figure 18] FIG. 2 is a schematic perspective view showing a configuration of a heat exchanger provided in the lubricant oil cooler; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an exemplary embodiment of the present invention will be described in detail with reference to the drawings. In the drawings, an XYZ coordinate system is appropriately shown as a three-dimensional orthogonal coordinate system. In the following description, the X direction is the front-rear direction, the Y direction is the left-right direction, and the Z direction is the up-down direction. The +X side is the front side, and the -X side is the rear side. The +Y side is the right side, and the -Y side is the left side. The +Z side is the upper side, and the -Z side is the lower side. In detail, the direction in which the center line C of the crankshaft (output shaft) shown in FIG. 1 extends is the front-rear direction, and the side where the flywheel 2 is arranged with respect to the cylinder block 1 is the rear side. In addition, the up-down direction is defined as the side where the oil pan 3 is arranged with respect to the cylinder block 1 is the lower side. The direction perpendicular to the front-rear direction and the up-down direction is defined as the left-right direction, and the side that is the right side when viewed from the rear toward the front is the right side, and the side that is the left side is the left side. In addition, these directions are names used simply for explanation, and are not intended to limit the actual positional relationship and direction. In this specification, the crankshaft direction is the same as the front-rear direction in which the center line C of the crankshaft extends.

[0011] <1. Engine Overview> Fig. 1 is a schematic perspective view showing a configuration of an engine 100 according to an embodiment of the present invention. The engine 100 is suitable as a marine engine for use in ships, for example. However, the engine 100 is not limited to being a marine engine and may be applied to other applications. The engine 100 is a diesel engine.

[0012] As shown in Fig. 1, engine 100 includes a cylinder block 1, a head block 4, and a head cover 5. The cylinder block 1 and the head block 4 form an engine block (engine body). That is, engine 100 includes an engine block. Fig. 2 is a schematic perspective view showing a portion of engine 100 that includes cylinder block 1, head block 4, and head cover 5. Fig. 3 is a schematic cross-sectional view of the cylinder block 1 portion of engine 100.

[0013] As shown in Figures 2 and 3, a crankshaft 6 and a piston 7 extending in the front-rear direction are disposed inside the cylinder block 1. The inside of the cylinder block 1 is connected to the inside of an oil pan 3 disposed below and storing lubricating oil. A flywheel 2 (see Figure 1) is attached to the rear end of the crankshaft 6. The flywheel 2 rotates integrally with the crankshaft 6 and is used to extract power from the engine 100. More specifically, the piston 7 is disposed in a cylinder 11 formed in the cylinder block 1. The piston 7 is connected to the crankshaft 6 via a connecting rod 71.

[0014] In detail, the cylinder block 1 has a right cylinder 11R arranged on the right side and a left cylinder 11L arranged on the left side. The right cylinder 11R is cylindrical inclined to the right side with respect to the vertical direction and extends in an oblique direction when viewed from the rear. The left cylinder 11L is cylindrical inclined to the left side with respect to the vertical direction and extends in an oblique direction when viewed from the rear. The right cylinder 11R and the left cylinder 11L are arranged in a V-shape. The pair of right cylinder 11R and left cylinder 11L arranged in a V-shape are arranged with the cylinder axes slightly shifted in the front-rear direction. In this embodiment, the left cylinder 11L is arranged slightly forward of the right cylinder 11R.

[0015] The cylinder block 1 has a right cylinder row 111R in which a plurality of right cylinders 11R are arranged in the front-rear direction, and a left cylinder row 111L in which a plurality of left cylinders 11L are arranged in the front-rear direction. That is, the engine 100 has two cylinder rows 111R, 111L. Each of the two cylinder rows 111R, 111L extends in the crankshaft direction. The two cylinder rows 111R, 111L are arranged side by side. In addition, the two cylinder rows 111R, 111L are arranged in the left-right direction in detail. The right cylinder row 111R and the left cylinder row 111L form a V-shaped bank. In this embodiment, the number of right cylinders 11R constituting the right cylinder row 111R and the number of left cylinders 11L constituting the left cylinder row 111L are both six, for example. That is, the engine 100 of this embodiment is a V-type 12-cylinder engine.

[0016] In each of the right cylinder row 111R and the left cylinder row 111L, a head block 4 is disposed overlapping each cylinder 11. The head block 4 is fastened to the cylinder block 1 using a screw. In detail, the head block 4 includes a right head block 4R overlapping the right cylinder 11R and a left head block 4L overlapping the left cylinder 11L. The right head blocks 4R are overlapped one by one on each of the right cylinders 11R, so that there are as many right cylinders 11R as there are right cylinders 11R. The left head blocks 4L are overlapped one by one on each of the left cylinders 11L, so that there are as many left cylinders 11L as there are left cylinders 11L. In this embodiment, the number of right head blocks 4R and left head blocks 4L is six.

[0017] Each head block 4 has an intake port 41 for supplying gas to a combustion chamber formed by the cylinder 11, piston 7, and head block 4, and an exhaust port (not shown) for exhausting gas from the combustion chamber. The exhaust port is provided on the surface opposite to the surface on which the intake port 41 is provided. In detail, the right head block 4R has an intake port 41 on its left side surface and an exhaust port on its right side surface. The left head block 4L has an intake port 41 on its right side surface and an exhaust port on its left side surface.

[0018] A head cover 5 is placed on top of each head block 4. The head cover 5 is fastened to the head block 4 with screws. Each head cover 5 covers an intake valve and an exhaust valve (not shown) arranged on the head block 4. An injector 8 is attached to each head cover 5. One end of the injector 8, which is provided with an injection port for injecting fuel, faces the combustion chamber. The other end of the injector 8 protrudes from the head cover 5 towards the outside.

[0019] In detail, the head cover 5 includes a right head cover 5R that is placed on the right head block 4R and a left head cover 5L that is placed on the left head block 4L. The right head covers 5R are placed on each right head block 4R, so there are the same number of right head covers 5R as the number of right head blocks 4R. The left head covers 5L are placed on each left head block 4L, so there are the same number of left head blocks 4L. In this embodiment, the number of right head covers 5R and left head covers 5L is six. The number of right injectors 8R arranged on the right head cover 5R and the number of left injectors 8L arranged on the left head cover 5L are also six.

[0020] On the right side of the cylinder block 1, the right cylinder 11R, the right head block 4R, and the right head cover 5R that constitute the right bank RB extend obliquely upward to the right. On the left side of the cylinder block 1, the left cylinder 11L, the left head block 4L, and the left head cover 5L that constitute the left bank LB extend obliquely upward to the left. In a plan view from the front-rear direction, the right bank RB and the left bank LB are V-shaped, and the engine 100 has a V-bank. An intra-bank area 200 is formed between the right bank RB and the left bank LB in the left-right direction.

[0021] Returning to FIG. 1, the engine 100 includes a top cover 9 and a side cover 10. The top cover 9 prevents water from splashing on the controller 26 (see FIG. 4, etc., described later) and other components disposed inside the engine 100 due to, for example, condensation. The side cover 10 prevents fuel from scattering due to, for example, cracks in components such as the head block 4. Although FIG. 1 only shows the side cover 10 disposed on the right side, a similar side cover 10 is also disposed on the left side. That is, the engine 100 includes a pair of left and right side covers 10.

[0022] Fig. 4 is a schematic top view showing the configuration of an engine 100 according to an embodiment of the present invention. In Fig. 4, the top cover 9 and the pair of side covers 10 are omitted. As shown in Figs. 1 and 4, the engine 100 includes an intake manifold 21 and an exhaust manifold 22. The intake manifold 21 and the exhaust manifold 22 are attached to an engine block (more specifically, the head block 4).

[0023] The intake manifold 21 distributes intake air, which is air or a mixture drawn in from the outside, to each cylinder 11. The intake manifold 21 is disposed on the upper part of the engine 100 and extends in the front-rear direction. In detail, the intake manifold 21 includes a right intake manifold 21R for the right cylinder 11R and a left intake manifold 21L for the left cylinder 11L. That is, the engine 100 includes two intake manifolds 21R, 21L.

[0024] The right intake manifold 21R is disposed above the intake ports 41 (see FIG. 2) of the multiple right head blocks 4R aligned in the front-rear direction. The interior of the right intake manifold 21R is connected to each of the right cylinders 11R via each of the intake ports 41. The left intake manifold 21L is disposed above the intake ports 41 of the multiple left head blocks 4L aligned in the front-rear direction. The interior of the left intake manifold 21L is connected to each of the left cylinders 11L via each of the intake ports 41.

[0025] In more detail, an intake valve (not shown) is interposed between each intake port 41 and each cylinder 11, and when the intake valve is opened, the inside of the intake manifold 21 and the cylinder 11 communicate with each other.

[0026] The exhaust manifold 22 collects exhaust from each cylinder 11. The exhaust manifold 22 is disposed on a side portion of the engine 100 and extends in the front-rear direction. In detail, the exhaust manifold 22 includes a right exhaust manifold 22R for the right cylinder 11R and a left exhaust manifold 22L for the left cylinder 11L.

[0027] The right exhaust manifold 22R is disposed on the right side of multiple right head blocks 4R (see FIG. 2) arranged in the front-rear direction. The interior of the right exhaust manifold 22R and each right cylinder 11R are connected via exhaust ports (not shown) provided on the right side of the right head block 4R. The left exhaust manifold 22L is disposed on the left side of multiple left head blocks 4L (see FIG. 2) arranged in the front-rear direction. The interior of the left exhaust manifold 22L and each left cylinder 11L are connected via exhaust ports (not shown) provided on the left side of the left head block 4L.

[0028] In more detail, an exhaust valve (not shown) is interposed between each exhaust port and each cylinder 11, and when the exhaust valve is opened, the inside of the exhaust manifold 22 and the cylinder 11 communicate with each other.

[0029] The exhaust gas collected in the right exhaust manifold 22R is exhausted to the outside via a right supercharger 23R and a right exhaust outlet pipe 24R arranged at the right rear of the engine 100. The exhaust gas collected in the left exhaust manifold 22L is exhausted to the outside via a left supercharger 23L and a left exhaust outlet pipe 24L arranged at the left rear of the engine 100.

[0030] The right supercharger 23R and the left supercharger 23L each have a compressor section 231 and a turbine section 232. The compressor section 231 pressurizes and compresses intake air such as air supplied from outside the engine 100. The pressurized and compressed intake air is supplied to the intake manifold 21 via the intercooler 25. The turbine section 232 is rotated by exhaust gas supplied from the exhaust manifold 22. The rotational power of the turbine section 232 is transmitted to the compressor section 231. That is, the right supercharger 23R and the left supercharger 23L of this embodiment are so-called turbochargers that use an exhaust gas turbine as a driving source. The engine 100 includes a supercharger 23 driven by exhaust gas from the exhaust manifold 22.

[0031] The intercooler 25 connected to the intake manifold 21 is supplied with cooling water by a cooling water pump (not shown) and cools the intake air. The intake air supplied from the compressor unit 231 is pressurized and compressed, generating compression heat and increasing the temperature. The intercooler 25 cools the intake air by exchanging heat between the cooling water supplied from the cooling water pump and the pressurized and compressed intake air. In other words, by providing the intercooler 25, the temperature of the intake air supplied to the intake manifold 21 can be adjusted to a desired temperature.

[0032] As shown in Fig. 4, the right intake manifold 21R and the left intake manifold 21L are arranged at a distance from each other in the left-right direction on the upper part of the engine 100. As shown in Fig. 4, when the top cover 9 is removed, the in-bank area 200 is exposed to the outside through the space between the right intake manifold 21R and the left intake manifold 21L. In the in-bank area 200, for example, a controller 26 that controls the entire engine 100, a fuel pump 27 that supplies fuel to the injector 8, etc. are arranged.

[0033] That is, the engine 100 includes a controller 26 disposed in an intra-bank area 200 located between the right cylinder row 111R and the left cylinder row 111L. The engine 100 also includes a fuel pump 27 disposed in the intra-bank area 200. Note that, strictly speaking, the intra-bank area 200 may be the spatial area between the right cylinder row 111R and the left cylinder row 111L. However, in this embodiment, the intra-bank area 200 broadly includes the spatial area in the left-right direction between the right bank RB including the right cylinder row 111R and the left bank LB including the left cylinder row 111L.

[0034] By arranging the controller 26 and the fuel pump 27 in the in-bank area 200, the in-bank area 200 can be efficiently used for arranging parts, thereby making it possible to reduce the size of the engine 100. However, the controller 26 and the fuel pump 27 may be arranged outside the in-bank area 200.

[0035] In addition, the controller 26 specifically includes a first controller 261 and a second controller 262. However, the number of controllers 26 may be changed as appropriate, and for example, the controller 26 may be configured with only one controller. In this embodiment, the first controller 261 and the second controller 262 are arranged in the front-rear direction (crankshaft direction). In detail, the first controller 261 is located forward of the second controller 262. One of the first controller 261 and the second controller 262 is a main controller, and the other is a sub-controller. In this embodiment, the first controller 261 is a main controller, and the second controller 262 is a sub-controller.

[0036] The first controller 261 configured as a main controller executes calculations necessary for controlling the engine 100. The calculations necessary for controlling the engine 100 include, for example, calculations related to control of fuel injection and calculations related to stopping the engine 100. The second controller 262 configured as a sub-controller is connected to the first controller 261 by a communication line (not shown) and is provided so as to be able to communicate with the first controller 261. The second controller 262 performs control operations according to instructions from the first controller 261.

[0037] The first controller 261 controls the right injector 8R arranged in the right bank RB. That is, the first controller 261 and each right injector 8R are electrically connected. The second controller 262 controls the left injector 8L arranged in the left bank LB. That is, the second controller 262 and each left injector 8L are electrically connected.

[0038] In addition, the fuel pump 27 pressurizes the fuel and discharges it toward a high-pressure fuel pipe (not shown) for the right bank RB and a high-pressure fuel pipe (not shown) for the left bank LB. The fuel passing through the high-pressure fuel pipe for the right bank RB is distributed to each right injector 8R arranged in the right bank RB. The fuel passing through the high-pressure fuel pipe for the left bank LB is distributed to each left injector 8L arranged in the left bank LB. Each injector 8 injects fuel into the combustion chamber under the control of the controller 26.

[0039] <2. Cooling system> The engine 100 of this embodiment is a liquid-cooled engine. The engine 100 includes a cylinder block 1 constituting an engine block, and a coolant flow path 50 (see FIG. 5 described later) through which a coolant flows to cool each of a plurality of head blocks 4. In this embodiment, the coolant is cooling water. However, the coolant may be a liquid other than water, such as antifreeze. The antifreeze is, for example, a liquid obtained by mixing pure water and ethylene glycol in a predetermined ratio.

[0040] FIG. 5 is a diagram showing a schematic configuration of a coolant flow path 50 provided in the engine 100 according to the embodiment of the present invention. In this embodiment, the coolant flow path 50 includes a first coolant flow path 50R and a second coolant flow path 50L. That is, the engine 100 includes the first coolant flow path 50R and the second coolant flow path 50L. The first coolant flow path 50R is provided for one of the two cylinder rows 111R and 111L. The second coolant flow path 50L is provided for the other of the two cylinder rows 111R and 111L. In detail, the first coolant flow path 50R is a coolant flow path provided for the right cylinder row 111R. The second coolant flow path 50L is a coolant flow path provided for the left cylinder row 111L.

[0041] The first coolant flow path 50R includes a coolant flow path 51R dedicated to the right cylinder row and a shared coolant flow path 52. The second coolant flow path 50L includes a coolant flow path 51L dedicated to the left cylinder row and a shared coolant flow path 52. The shared coolant flow path 52 is a coolant flow path shared by both the first coolant flow path 50R and the second coolant flow path 50L.

[0042] As shown in Fig. 5, the shared coolant flow path 52 includes a coolant pump 30, a coolant cooler 31, a lubricant cooler 32, and a thermostat case 34 that houses a thermostat 33. Fig. 6 is a schematic front view showing a configuration of an engine 100 according to an embodiment of the present invention. Fig. 6 is a view of the engine 100 viewed from the front toward the rear. As shown in Fig. 6, the coolant pump 30, the coolant cooler 31, the lubricant cooler 32, and the thermostat case 34 are disposed at the front end of the engine 100.

[0043] The coolant pump 30 circulates the coolant through the coolant flow path 50. The coolant pump 30 is driven by rotational power transmitted from the crankshaft 6 via a gear (not shown). In this embodiment, the coolant pump 30 is a cooling water pump.

[0044] The coolant cooler 31 cools the coolant circulating through the coolant flow path 50. In this embodiment, the coolant cooler 31 is a fresh water cooler. The coolant cooler 31 cools the coolant circulating through the coolant flow path 50 by utilizing heat exchange with seawater pumped up by driving the seawater pump 35. The seawater pump 35 is disposed at the front end of the engine 100. The seawater pump 35 is driven by rotational power transmitted from the crankshaft 6 via a gear (not shown). In this embodiment, the seawater pumped up by the seawater pump 35 is sent to the intercooler 25, reaches the coolant cooler 31, and is discharged to the outside (sea). That is, the seawater pump 35 is an example of a cooling water pump that supplies cooling water to the intercooler 25 described above.

[0045] The lubricant cooler 32 cools the lubricant. The lubricant is supplied to each part of the engine 100 from the oil pan 3 by driving a lubricant pump (not shown), and returns to the oil pan 3. The lubricant cooler 32 also constitutes a flow path for the lubricant. The lubricant cooler 32 cools the lubricant by using the coolant flowing through the coolant flow path 50. The lubricant pump is driven by rotational power transmitted from the crankshaft 6 via a gear (not shown).

[0046] The thermostat case 34 covers the thermostat 33 disposed in the coolant cooler 31, and constitutes the coolant flow path 50. The thermostat 33 has a function of keeping the temperature of the coolant near a set temperature. Due to the function of the thermostat 33, the coolant that needs to be cooled is sent to the coolant cooler 31.

[0047] The coolant discharged from the coolant pump 30 is sent to the coolant flow path 51R dedicated to the right cylinder row and the coolant flow path 51L dedicated to the left cylinder row. The coolant that has passed through each of the coolant flow paths 51R dedicated to the right cylinder row and the coolant flow path 51L dedicated to the left cylinder row is sent to a thermostat case 34 that houses a thermostat 33. The coolant sent to the thermostat case 34 includes coolant that is sent to the coolant cooler 31 by the action of the thermostat 33 and coolant that returns to the coolant pump 30 without being sent to the coolant cooler 31. The coolant sent to the coolant cooler 31 is cooled by a heat exchanger 311 (see FIG. 6) of the coolant cooler 31, and sent to a coolant tank 312 (see FIG. 6) of the coolant cooler 31. The coolant stored in the coolant tank 312 is sent to the coolant pump 30 as appropriate. In addition, a portion of the coolant sent to the coolant cooler 31 returns to the coolant pump 30 via the lubricant oil cooler 32 .

[0048] FIG. 7 is a schematic perspective view showing parts constituting a part of the right cylinder row-dedicated coolant flow path 51R and the left cylinder row-dedicated coolant flow path 51L. In FIG. 7, the white arrows indicate the flow of the coolant. As shown in FIG. 7, the parts constituting the right cylinder row-dedicated coolant flow path 51R include the right exhaust manifold 22R, the right coolant collecting pipe 28R, and the right exhaust connecting pipe 29R. The parts constituting the left cylinder row-dedicated coolant flow path 51L include the left exhaust manifold 22L, the left coolant collecting pipe 28L, and the left exhaust connecting pipe 29L.

[0049] The right exhaust manifold 22R and the left exhaust manifold 22L are cylindrical and extend in the front-rear direction. FIG. 8 is a schematic cross-sectional perspective view showing a cross section cut at the VIII-VIII position shown in FIG. 7. In FIG. 8, the thick arrows indicate the flow of the coolant. As shown in FIG. 8, each of the right exhaust manifold 22R and the left exhaust manifold 22L has an internal exhaust pipe 222 communicating with an exhaust gas inlet 221 provided on the inner side surface. Note that a plurality of exhaust gas inlets 221 are provided in each of the exhaust manifolds 22R and 22L in the front-rear direction, and each of them communicates with an exhaust port provided in each head block 4. In each of the right exhaust manifold 22R and the left exhaust manifold 22L, the coolant flows through the internal space SP1 of each of the exhaust manifolds 22R and 22L. In detail, the coolant flows around the internal exhaust pipe 222 arranged in the internal space SP1.

[0050] The right cooling liquid collecting pipe 28R and the left cooling liquid collecting pipe 28L are cylindrical and extend in the front-rear direction. The right cooling liquid collecting pipe 28R is arranged next to the right exhaust manifold 22R and attached to the right exhaust manifold 22R. The right cooling liquid collecting pipe 28R is arranged diagonally above the right exhaust manifold 22R. The left cooling liquid collecting pipe 28L is arranged next to the left exhaust manifold 22L and attached to the left exhaust manifold 22L. The left cooling liquid collecting pipe 28L is arranged diagonally above the left exhaust manifold 22L.

[0051] A plurality of coolant holes 281 are provided on the inner side surface of each of the right coolant collecting pipe 28R and the left coolant collecting pipe 28L. In each of the coolant collecting pipes 28R, 28L, the same number of coolant holes 281 as the number of cylinders constituting each of the cylinder rows 111R, 111L are arranged at intervals in the front-rear direction. In this embodiment, the number of coolant holes 281 provided in each of the coolant collecting pipes 28R, 28L is six.

[0052] Each of the coolant holes 281 is connected to a coolant flow path provided in each head block 4 by a coolant pipe (not shown). The coolant discharged from the coolant pipe connected to the coolant flow path of each head block 4 constituting the right bank RB flows into the internal space SP2 of the right coolant collecting pipe 28R via each of the coolant holes 281. The coolant discharged from the coolant pipe connected to the coolant flow path of each head block 4 constituting the left bank LB flows into the internal space SP2 of the left coolant collecting pipe 28L via each of the coolant holes 281.

[0053] As shown in FIG. 7, the right exhaust communication pipe 29R is connected to the rear end of the right exhaust manifold 22R. The left exhaust communication pipe 29L is connected to the rear end of the left exhaust manifold 22L. As shown in FIG. 1, the right exhaust communication pipe 29R is connected to the turbine section 232 of the right supercharger 23R. The left exhaust communication pipe 29L is connected to the turbine section 232 of the left supercharger 23L. In other words, the right exhaust communication pipe 29R connects the right exhaust manifold 22R and the right supercharger 23R. The left exhaust communication pipe 29L connects the left exhaust manifold 22L and the left supercharger 23L. That is, the engine 100 is provided with an exhaust communication pipe 29 that connects the exhaust manifold 22 and the supercharger 23.

[0054] Fig. 9 is a schematic perspective view showing the configuration of the right exhaust communication pipe 29R provided in the engine 100 according to the embodiment of the present invention. In Fig. 9, the thick arrows indicate the flow of the coolant. The left exhaust communication pipe 29L has the same main configuration as the right exhaust communication pipe 29R. For this reason, the configuration of the exhaust communication pipe 29 will be described using the right exhaust communication pipe 29R as a representative example.

[0055] 9, the right exhaust connection pipe 29R has an internal space SP3. An internal connection pipe exhaust pipe 291, through which exhaust gas passes, is disposed in this internal space SP3. An exhaust inlet 292, which is connected to one end of the internal connection pipe exhaust pipe 291, is provided in front of the right exhaust connection pipe 29R. When the right exhaust connection pipe 29R and the right exhaust manifold 22R are connected, the internal connection pipe exhaust pipe 291 and the internal manifold exhaust pipe 222 communicate with each other.

[0056] Further, the right exhaust communication pipe 29R is provided with an exhaust outlet 293 connected to the other end of the exhaust pipe 291 in the communication pipe. When the right exhaust communication pipe 29R is connected to the turbine section 232 of the right supercharger 23R, the exhaust pipe 291 in the communication pipe communicates with the inside of the turbine section 232. That is, exhaust gas from each combustion chamber of the right bank RB is sent to the turbine section 232 of the right supercharger 23R through the exhaust pipe 222 in the manifold of the right exhaust manifold 22R and the exhaust pipe 291 in the communication pipe of the right exhaust communication pipe 29R. Similarly, exhaust gas from each combustion chamber of the left bank LB is sent to the turbine section 232 of the left supercharger 23L through the exhaust pipe 222 in the manifold of the left exhaust manifold 22L and the exhaust pipe 291 in the communication pipe of the left exhaust communication pipe 29L.

[0057] As shown in FIG. 9, the right exhaust communication pipe 29R is provided with a coolant inlet 294, which is an inlet for the coolant. More specifically, the coolant inlet 294 is provided on the right side surface of the right exhaust communication pipe 29R. However, the location where the coolant inlet 294 is provided may be changed as appropriate. As shown in FIG. 7, the coolant inlet 294 communicates with the internal space SP2 of the right coolant collecting pipe 28R via the coolant communication pipe 36. In addition, a coolant outlet 295, which is an outlet for the coolant, is provided on the front surface of the right exhaust communication pipe 29R. When the right exhaust communication pipe 29R and the right exhaust manifold 22R are connected, the coolant outlet 295 communicates with the internal space SP1 of the right exhaust manifold 22R.

[0058] In the right exhaust connecting pipe 29R, the coolant that enters the internal space SP3 from the coolant inlet 294 flows around the connecting pipe exhaust pipe 291 and is discharged from the coolant outlet 295. Similarly, in the left exhaust connecting pipe 29L, the coolant that enters the internal space SP3 from the coolant inlet 294 flows around the connecting pipe exhaust pipe 291 and is discharged from the coolant outlet 295.

[0059] The coolant discharged from the coolant pump 30 and flowing through the coolant flow passage 51R dedicated to the right cylinder row is sent to the coolant flow passage for the right cylinder row 111R provided in the cylinder block 1 and each head block 4 constituting the right bank RB. As shown by the outlined arrows in Figure 7, the coolant discharged from each head block 4 constituting the right bank RB flows in this order through the right exhaust connecting pipe 29R and the right exhaust manifold 22R.

[0060] In addition, the coolant discharged from the coolant pump 30 and flowing through the left cylinder row-specific coolant flow path 51L is sent to the cylinder block 1 and a coolant flow path for the left cylinder row 111L provided in each head block 4 that constitutes the left bank LB. As indicated by the outlined arrows in Figure 7, the coolant discharged from each head block 4 that constitutes the left bank LB flows in this order through the left exhaust connecting pipe 29L and the left exhaust manifold 22L.

[0061] That is, in this embodiment, the engine 100 includes a coolant flow passage 50 that causes the coolant discharged from the engine block to flow through the exhaust connecting pipe 29 and the exhaust manifold 22 in this order. With this configuration, the engine block (cylinder block 1 and head block 4), which is an important part of the engine 100, can be first cooled with the coolant. Then, by sending the relatively low-temperature coolant discharged from the engine block to the exhaust connecting pipe 29 first instead of the exhaust manifold 22, the part of the engine 100 before the turbocharger 23, which is likely to become particularly hot, can be preferentially cooled. This makes it possible to appropriately suppress a temperature rise at the exhaust inlet part of the turbocharger 23, and suppress an excessive rise in the temperature of the turbocharger 23.

[0062] In detail, the coolant discharged from each head block 4 constituting the right bank RB flows in the order of the right coolant collecting pipe 28R, the right exhaust connecting pipe 29R, and the right exhaust manifold 22R. Also, the coolant discharged from each head block 4 constituting the left bank LB flows in the order of the left coolant collecting pipe 28L, the left exhaust connecting pipe 29L, and the left exhaust manifold 22L. In other words, the coolant flow path 50 includes the coolant collecting pipe 28 that collects the coolant discharged from multiple points in the engine block and discharges it to the exhaust connecting pipe 29.

[0063] In this embodiment, the exhaust manifold 22 and the coolant collecting pipe 28 are disposed parallel to the crankshaft 6. In other words, the exhaust manifold 22 and the coolant collecting pipe 28 are disposed side by side with the crankshaft 6. In detail, the exhaust manifold 22 and the coolant collecting pipe 28 are disposed side by side with the crankshaft 6 in the left-right direction. More specifically, the right exhaust manifold 22R and the right coolant collecting pipe 28R are disposed side by side on the right side of the crankshaft 6. The left exhaust manifold 22L and the left coolant collecting pipe 28L are disposed side by side on the left side of the crankshaft 6.

[0064] At least a part of the turbocharger 23 is disposed on one side of the exhaust manifold 22 in the crankshaft direction. In this example, the one side of the crankshaft direction refers to the rear side. In detail, at least a part of the right turbocharger 23R is disposed rearward of the right exhaust manifold 22R and the right cooling liquid collecting pipe 28R. At least a part of the left turbocharger 23L is disposed rearward of the left exhaust manifold 22L and the left cooling liquid collecting pipe 28L. By disposing in this way, the structure connecting the exhaust connecting pipe 29 disposed near the turbocharger 23 to both the cooling liquid collecting pipe 28 and the exhaust manifold 22 can be configured without having a complex shape. That is, the cooling liquid flow path in which the cooling liquid flows in the order of the cooling liquid collecting pipe 28, the exhaust connecting pipe 29, and the exhaust manifold 22 can be formed as a compact and simple structure.

[0065] Coolant flow path components to which the coolant that has flowed through the exhaust manifold 22 is sent are disposed at the other end of the engine 100 in the crankshaft direction. In this example, the other end in the crankshaft direction refers to the front side. As shown by the white arrows in FIG. 7, the coolant that flows through the right exhaust manifold 22R and the left exhaust manifold 22L flows from the rear to the front. For this reason, by disposing the coolant flow path components at the rear end of the engine 100, the components that make up the engine 100 can be disposed efficiently.

[0066] The coolant flow path components may broadly include components that configure the coolant flow path. The coolant flow path components may include, for example, cooling pipes through which the coolant flows. The coolant flow path components are preferably components related to cooling the coolant. In detail, the coolant flow path components preferably include at least one of a thermostat case 34 that houses a thermostat 33 and a coolant cooler 31. The coolant discharged from the exhaust manifold 22 is hotter than when it is discharged from the coolant pump 30 after absorbing heat from exhaust gas and the like. For this reason, by configuring the coolant cooler 31 and the thermostat 33 used in combination with the coolant cooler 31 to be disposed near the location where the coolant is discharged from the exhaust manifold 22, the coolant can be effectively cooled to maintain the cooling performance.

[0067] In this embodiment, the coolant cooler 31 is a fresh water cooler as described above, but it may be something other than a fresh water cooler, for example, a radiator. In other words, the category of coolant coolers may include fresh water coolers and radiators.

[0068] The first coolant flow path 50R includes a right coolant collecting pipe (first coolant collecting pipe) 28R that collects the coolant that has cooled one of the two cylinder rows 111R, 111L. The first coolant flow path 50R further includes a water-cooled right exhaust connecting pipe 29R connected to the right coolant collecting pipe 28R, and a water-cooled right exhaust manifold 22R connected to the right exhaust connecting pipe 29R. In detail, the right coolant collecting pipe 28R, the water-cooled right exhaust connecting pipe 29R, and the water-cooled right exhaust manifold 22R configure a coolant flow path 51R dedicated to the right cylinder row.

[0069] The second coolant flow path 50L includes a left coolant collecting pipe (second coolant collecting pipe) 28L that collects the coolant that has cooled the other of the two cylinder rows 111R, 111L. The second coolant flow path 50L further includes a water-cooled left exhaust connecting pipe 29L connected to the left coolant collecting pipe 28L, and a water-cooled left exhaust manifold 22L connected to the left exhaust connecting pipe 29L. In detail, the left coolant collecting pipe 28L, the water-cooled left exhaust connecting pipe 29L, and the water-cooled left exhaust manifold 22L configure a coolant flow path 51L dedicated to the left cylinder row.

[0070] In this embodiment, as shown in Fig. 7, the coolant discharged from the right exhaust manifold 22R flows into the coolant flow path provided in the gear case 40 via the cooling pipe 37. The coolant discharged from the left exhaust manifold 22L flows into the coolant flow path provided in the gear case 40 via the cooling pipe 37. That is, the engine 100 includes a gear case 40 in which a part of the first coolant flow path 50R and a part of the second coolant flow path 50L are provided. However, this is merely an example, and the gear case may be configured to include a part of the first coolant flow path 50R and / or a part of the second coolant flow path 50L.

[0071] The gear case 40 houses gears (not shown) that transmit the rotational power of the crankshaft 6 to a rotating shaft of the coolant pump 30, the seawater pump 35, an alternator (not shown), etc. That is, the configuration of this embodiment is such that the coolant flow paths 50 for the two cylinder rows 111R and 111L are formed using the gear case 40, which is an accessory part originally provided on the engine 100. Therefore, in the engine 100 having the two cylinder rows 111R and 111L, the coolant flow paths can be configured while suppressing an increase in the number of parts. Since the number of parts can be reduced, the space for arranging the coolant flow paths can be reduced, and the engine 100 can be made more compact.

[0072] In this embodiment, the coolant pump 30 and the seawater pump 35 are attached to a gear case 40. The gear case 40 is disposed forward of the two cylinder rows 111R and 111L. The gear case 40 is disposed forward of the engine block.

[0073] FIG. 10 is a schematic perspective view showing the configuration of the gear case 40 provided in the engine 100 according to the embodiment of the present invention. FIG. 11 is a schematic perspective view of the gear case 40 when the gear case 40 is viewed from a direction different from that in FIG. 10. FIG. 10 is a view of the gear case 40 viewed from the right diagonal front. FIG. 11 is a view of the gear case 40 viewed from the right diagonal rear. FIG. 12 is a schematic right side view showing the configuration of the gear case 40 provided in the engine 100. FIG. 13 is a schematic sectional perspective view showing a cross section cut at position XIII-XIII shown in FIG. 12. FIG. 14 is a schematic sectional perspective view showing a cross section cut at position XIV-XIV shown in FIG. 12. In FIG. 10, FIG. 11, FIG. 13, and FIG. 14, thick arrows indicate the flow of the coolant.

[0074] As shown in Figs. 10 to 14, the gear case 40 is a plate-like member having a thickness in the front-rear direction and extending in a direction perpendicular to the front-rear direction. In a plan view from the front-rear direction, the gear case 40 has a crankshaft hole 401 penetrating in the front-rear direction near the lower center. The front end of the crankshaft 6 is inserted in the crankshaft hole 401. The gear case 40 also has a bearing accommodating recess 402 in front of the crankshaft hole 401. The bearing accommodating recess 402 is recessed from the front to the rear and accommodates the bearing 38 (see Fig. 6) that rotatably supports the crankshaft 6. The gear case 40 also has a gear accommodating recess 403 on its rear surface that is recessed toward the front. The gear accommodating recess 403 accommodates a plurality of gears (not shown) that transmit the rotational power of the crankshaft 6. The plurality of gears includes, for example, a gear that transmits the rotational power to the coolant pump 30 and a gear that transmits the rotational power to the seawater pump 35. The gear case 40 also has a coolant pump mounting opening 404 on the right front side, to which the coolant pump 30 is attached. The gear case 40 also has a seawater pump mounting opening 405 on the left front side, to which the seawater pump 35 is attached.

[0075] The gear case 40 has a right side coolant inlet 406R at an upper right side thereof, which receives coolant from the right coolant collecting pipe 28R. The right side coolant inlet 406R is connected to a first case internal flow path 407R for the right cylinder row (see FIG. 13) provided inside the gear case 40. The first case internal flow path 407R for the right cylinder row is provided at an upper portion of the gear case 40 and extends in the left-right direction. The first case internal flow path 407R for the right cylinder row is included in the first coolant flow path 50R, and more specifically, is included in the coolant flow path 51R dedicated to the right cylinder row.

[0076] The gear case 40 also has a left side coolant inlet 406L at an upper left side for receiving coolant from the left coolant collecting pipe 28L. The left side coolant inlet 406L is connected to a first case internal flow passage 407L for the left cylinder row (see FIG. 13) provided inside the gear case 40. The first case internal flow passage 407L for the left cylinder row is provided at an upper portion of the gear case 40, and is disposed to the left of the first case internal flow passage 407R for the right cylinder row. The first case internal flow passage 407L for the left cylinder row is included in the second coolant flow passage 50L, and more specifically, is included in the coolant flow passage 51L dedicated to the left cylinder row.

[0077] The first case internal flow passage 407R for the right cylinder row and the first case internal flow passage 407L for the left cylinder row are separated by a partition wall 408 extending in the vertical direction in the gear case 40. That is, the gear case 40 has the partition wall 408 that separates the first coolant flow passage 50R and the second coolant flow passage 50L. A difference in water pressure may occur between the coolant entering the case from the right side coolant inlet 406R and the coolant entering the case from the left side coolant inlet 406L. In such a case, if the partition wall 408 is not provided, a backflow due to the pressure difference may occur. By providing the partition wall 408, it is possible to prevent such a backflow due to the pressure difference. In addition, if the cooling liquid entering the case from the right side coolant inlet 406R and the cooling liquid entering the case from the left side coolant inlet 406L both have sufficient pressure and flow downstream without backflow due to pressure difference, the partition 408 may not be provided and the cooling liquid entering the case from the right side coolant inlet 406R and the cooling liquid entering the case from the left side coolant inlet 406L may be configured to merge inside the gear case 40.

[0078] An upper right surface coolant outlet 409R and an upper left surface coolant outlet 409L are provided on the upper surface of the gear case 40. The upper right surface coolant outlet 409R and the left upper surface coolant outlet 409L are arranged side by side on the left and right sides near the left end of the upper surface of the gear case 40. The upper right surface coolant outlet 409R is arranged to the right of the left upper surface coolant outlet 409L. The upper right surface coolant outlet 409R is connected to the first case internal flow path 407R for the right cylinder row. The left upper surface coolant outlet 409L is connected to the first case internal flow path 407L for the left cylinder row.

[0079] The coolant that enters the first case flow passage 407R for the right cylinder row from the right side coolant inlet 406R is discharged from the right upper side coolant outlet 409R to the outside of the case and sent to the thermostat case 34. The coolant that enters the first case flow passage 407L for the left cylinder row from the left side coolant inlet 406L is discharged from the left upper side coolant outlet 409L to the outside of the case and sent to the thermostat case 34. That is, the coolant that enters the gear case 40 from the right coolant collecting pipe (first coolant collecting pipe) 28R and the left coolant collecting pipe (second coolant collecting pipe) 28L is discharged to the thermostat case 34 that houses the thermostat 33. However, this is merely an example, and the coolant that enters the gear case 40 from the right coolant collecting pipe 28R and / or the left coolant collecting pipe 28L may be discharged to the thermostat case 34 that houses the thermostat 33.

[0080] As shown in FIG. 10 and FIG. 14, the gear case 40 has a first front coolant inlet 410 at the upper right side of the front surface, which guides the coolant discharged from the lubricant oil cooler 32 into the inside of the case. The gear case 40 has a common case internal flow path 411 connected to the first front coolant inlet 410 inside. The common case internal flow path 411 is included in the common coolant flow path 52. The gear case 40 has a front coolant outlet 412 connected to the common case internal flow path 411 at the right end of the front surface. The front coolant outlet 412 is disposed to the right and below the first front coolant outlet 410. The coolant that has entered the common case internal flow path 411 from the first front coolant inlet 410 is discharged from the case to the outside from the front coolant outlet 412 and sent to the coolant pump 30.

[0081] As can be seen from the above, the gear case 40 has the shared coolant flow path 52 that is shared by both the first coolant flow path 50R and the second coolant flow path 50L. In detail, the gear case 40 has a part of the shared coolant flow path 52. The shared coolant flow path 52 provided in the gear case 40 includes a flow path that guides the coolant discharged from the lubricant oil cooler 32 that cools the lubricant oil to the coolant pump 30.

[0082] 10 and 14, the gear case 40 has a second front surface coolant inlet 413 at the center of the front surface, which guides the coolant discharged from the coolant pump 30 into the inside of the case. The gear case 40 has a branching portion 414 inside, which is connected to the second front surface coolant inlet 413 and divides the coolant into the first coolant flow path 50R and the second coolant flow path 50L. The branching portion 414 is included in the shared coolant flow path 52.

[0083] 14, the gear case 40 has therein a second case flow passage 415R for the right cylinder row that is connected to the branching portion 414 and extends obliquely downward to the right. The second case flow passage 415R for the right cylinder row is included in the first coolant flow passage 50R, and more specifically, is included in the coolant flow passage 51R exclusively for the right cylinder row. The gear case 40 also has therein a second case flow passage 415L for the left cylinder row that is connected to the branching portion 414 and extends obliquely downward to the left. The second case flow passage 415L for the left cylinder row is included in the second coolant flow passage 50L, and more specifically, is included in the coolant flow passage 51L exclusively for the left cylinder row.

[0084] 11, the gear case 40 has a right rear coolant outlet 416R connected to the second case flow passage 415R for the right cylinder row at the right end of the lower rear surface, and a left rear coolant outlet 416L connected to the second case flow passage 415L for the left cylinder row at the left end of the lower rear surface.

[0085] The cooling liquid discharged from the cooling liquid pump 30 is separated at the branching portion 414 into the cooling liquid flowing through the second case internal flow passage 415R for the right cylinder row and the cooling liquid flowing through the second case internal flow passage 415L for the left cylinder row. The cooling liquid flowing through the second case internal flow passage 415R for the right cylinder row is discharged to the outside of the case from the right rear cooling liquid outlet 416R and sent to the cooling flow passage for the right cylinder row provided in the cylinder block 1. The cooling liquid flowing through the second case internal flow passage 415L for the left cylinder row is discharged to the outside of the case from the left rear cooling liquid outlet 416L and sent to the cooling flow passage for the left cylinder row provided in the cylinder block 1.

[0086] As can be seen from the above, a part of the first coolant flow path 50R provided in the gear case 40 includes a flow path that guides the coolant supplied from the coolant pump 30 to one of the two cylinder rows 111R, 111L. Also, a part of the second coolant flow path 50L provided in the gear case 40 includes a flow path that guides the coolant supplied from the coolant pump 30 to the other of the two cylinder rows 111R, 111L. In this example, one of the two cylinder rows 111R, 111L is the right cylinder row 111R. The other of the two cylinder rows 111R, 111L is the left cylinder row 111L.

[0087] In this embodiment, a plurality of types of flow paths for flowing the coolant are provided inside the gear case 40, and the coolant flow paths 50 can be efficiently formed.

[0088] <3. Coolant cooler and lubricant oil cooler> As described above, the engine 100 includes the coolant cooler 31 and the lubricant cooler 32. The coolant cooler 31 cools the coolant that cools the engine block (engine body). The lubricant cooler 32 cools the lubricant using the coolant that cools the engine block. In the present embodiment, the lubricant cooler 32 cools the lubricant using the coolant cooled by the coolant cooler 31, but this is an example. The lubricant cooler 32 may be cooled by a coolant different from the coolant cooled by the coolant cooler 31. That is, the lubricant cooler 32 may be configured to cool the lubricant using a first coolant that cools the engine block, or a second coolant different from the first coolant. For example, the first coolant may be fresh water, and the second coolant may be seawater.

[0089] 6, the coolant cooler 31 and the lubricant oil cooler 32 are arranged side by side on one end side in the crankshaft direction of the engine 100. In this example, the one end side in the crankshaft direction is the front end side. The coolant cooler 31 and the lubricant oil cooler 32 are arranged side by side on the front side of the engine 100.

[0090] By arranging the coolant cooler 31 and the lubricant oil cooler 32 side by side at one end in the crankshaft direction of the engine 100, it is possible to suppress an increase in the length in the crankshaft direction of the engine 100 compared to a case in which these coolers 31, 32 are arranged separately at one end and the other end in the crankshaft direction. Also, by arranging the coolant cooler 31 and the lubricant oil cooler 32 side by side at one end in the crankshaft direction of the engine 100, it is possible to suppress an increase in the length in the width direction of the engine 100 compared to a case in which at least one of these coolers 31, 32 is arranged on a side of the engine 100.

[0091] When the engine 100 is a V-engine having two cylinder rows 111R, 111L as in this embodiment, the area of ​​the end face in the crankshaft direction of the engine 100 is large. For this reason, the engine 100 of this embodiment makes it easy to arrange the coolant cooler 31 and the lubricant oil cooler 32 side by side on one end face in the crankshaft direction. Furthermore, according to the engine 100 of this embodiment, even when the two coolers 31, 32 are arranged side by side on one end face in the crankshaft direction, the size of each of the coolers 31, 32 in the vertical and horizontal directions can be increased.

[0092] In this embodiment, the coolant cooler 31 and the lubricant oil cooler 32 are arranged side by side in the left-right direction. However, the direction in which the coolant cooler 31 and the lubricant oil cooler 32 are arranged side by side is not limited to the left-right direction, and may be, for example, the up-down direction.

[0093] The gear case 40 included in the engine 100 may be disposed between the engine block (cylinder block 1, etc.) and the coolant cooler 31 and / or the lubricant cooler 32. The coolant cooler 31 and / or the lubricant cooler 32 may be attached to the gear case 40. In this embodiment, the gear case 40 is disposed between the engine block and the coolant cooler 31 and the lubricant cooler 32. In detail, the gear case 40 is disposed between the engine block and the coolant cooler 31 in the crankshaft direction. The coolant cooler 31 and the lubricant cooler 32 are attached to the gear case 40.

[0094] By configuring the coolant cooler 31 and the lubricant oil cooler 32 to be attached to the gear case 40 that is originally provided in the engine 100, it is possible to avoid an increase in the number of parts of the engine 100. This makes it possible to make the engine 100 more compact. In addition, since the gear case 40 is directly fixed to the cylinder block 1, it is less likely to shake. Therefore, by configuring the coolant cooler 31 and the lubricant oil cooler 32 to be attached to the gear case 40, it is possible to suppress vibration of each cooler 31, 32.

[0095] Fig. 15 is a schematic perspective view showing the mounting structure of the coolant cooler 31 and the lubricant oil cooler 32 included in the engine 100 according to the embodiment of the present invention. The lower part of the coolant cooler 31 is directly mounted to the gear case 40 using a fastener such as a screw. The upper part of the coolant cooler 31 is mounted to a coolant cooler support member 61 (see Fig. 15) using a fastener such as a screw. The coolant cooler support member 61 is an L-shaped sheet metal member, and is mounted to the upper surface of the gear case 40. That is, the upper part of the coolant cooler 31 is indirectly mounted to the gear case 40 by using the coolant cooler support member 61.

[0096] In this embodiment, there are two coolant cooler support members 61, and the two coolant cooler support members 61 are lined up on the left and right at the center of the top surface of the gear case 40. However, the number of coolant cooler support members 61 may be changed as appropriate. In addition to the coolant cooler support members 61, a pipe 62 through which the coolant flows is also attached to the top surface of the gear case 40. The pipe 62 is also attached to the coolant cooler 31. It can be said that the upper part of the coolant cooler 31 is supported by the coolant cooler support members 61 and the pipe 62.

[0097] The lower part of the lubricant oil cooler 32 is directly attached to the gear case 40 using a fastener such as a screw. The upper part of the lubricant oil cooler 32 is attached to a lubricant oil cooler support member 63 (see FIG. 15) using a fastener such as a screw. The lubricant oil cooler support member 63 is attached to the upper surface of the gear case 40. That is, the upper part of the lubricant oil cooler 32 is indirectly attached to the gear case 40 by using the lubricant oil cooler support member 63. In this embodiment, the lubricant oil cooler support member 63 has flow paths for the coolant and the lubricant therein.

[0098] As described above, the gear case 40 has a flow path through which the coolant passes inside. That is, the gear case 40 has an in-case coolant flow path through which the coolant passes. The in-case coolant flow path includes a first flow path arranged upstream of the coolant cooler 31 and a second flow path arranged downstream of the coolant cooler 31. In this embodiment, the second flow path is arranged downstream of the lubricant cooler 32. In this embodiment, the terms "upstream" and "downstream" are used to refer to a section from the coolant pump 30 that discharges the coolant to the section where the outflowing coolant returns to the coolant pump 30. At a certain point in the coolant flow path, the upstream side is the side that moves in the opposite direction to the direction in which the coolant flows, and the downstream side is the side that moves in the same direction as the direction in which the coolant flows.

[0099] In detail, the first flow path constitutes a flow path of the coolant that has exchanged heat with the exhaust gas before entering the coolant cooler 31. That is, the first flow path constitutes a flow path between the exhaust manifold 22 and the coolant cooler 31. The first flow path includes the first case internal flow path 407R for the right cylinder row and the first case internal flow path 407L for the left cylinder row (see FIG. 13, for example). The second flow path constitutes a flow path between the lubricant cooler 32 and the coolant pump 30. The second flow path includes the common case internal flow path 411 (see FIG. 14) described above. By using the inside of the gear case 40 as a flow path through which the coolant passes, the cooling flow path can be arranged efficiently. By using the inside of the gear case 40 as a flow path through which the coolant passes, the number of parts can be reduced.

[0100] In this embodiment, the gear case 40 also includes a third flow path disposed downstream of the coolant pump 30. More specifically, the third flow path constitutes an internal case flow path through which the coolant discharged from the coolant pump 30 passes before entering a coolant flow path provided in the engine block. The third flow path includes the second internal case flow path 415R for the right cylinder row and the second internal case flow path 415L for the left cylinder row described above.

[0101] Fig. 16 is a schematic perspective view showing the configuration of the heat exchanger 311 included in the coolant cooler 31. In Fig. 16, the white arrow P1 indicates the flow of the coolant that cools the engine block. In detail, the white arrow P1 indicates the flow of fresh water. The thick black arrow P2 indicates the flow of seawater that cools the fresh water.

[0102] 16, the heat exchange unit 311 of the coolant cooler 31 has, on its rear surface, a fresh water inlet 3111 which is an inlet for fresh water, and a fresh water outlet 3112 which is an outlet for fresh water. The heat exchange unit 311 also has, on its rear surface, a seawater inlet 3113 which is an inlet for seawater. The heat exchange unit 311 has, on its front surface, a seawater outlet 3114 (see FIG. 17 described later) which is an outlet for seawater. A seawater outlet pipe 3115 is provided at the seawater outlet 3114, such that the flow direction of seawater discharged from the outlet is downward.

[0103] FIG. 17 is a schematic diagram for explaining the configuration of the heat exchanger 311 of the coolant cooler 31. In FIG. 17, the heat exchanger 311 is partially disassembled. As in FIG. 16, in FIG. 17, the outlined arrow P1 indicates the flow of fresh water, and the thick black arrow P2 indicates the flow of seawater. As shown in FIG. 17, the heat exchanger 311 has a front frame 3116 and a rear frame 3117. The heat exchanger 311 also has a plurality of plates 3118 between the front frame 3116 and the rear frame 3117 in the front-rear direction. The plurality of plates 3118 are stacked in the front-rear direction and sandwiched between the front frame 3116 and the rear frame 3117.

[0104] In the heat exchange section 311 of the coolant cooler 31, fresh water or seawater flows between the plates 3118. In detail, the type of liquid flowing between the two plates 3118 alternates. For example, the type of liquid flowing between the two plates 3118 alternates between fresh water, seawater, fresh water, seawater, and so on from the rear to the front. With this configuration, heat can be efficiently exchanged between the fresh water and seawater. The heat exchange section 311 is a so-called multi-plate type heat exchange section. That is, the coolant cooler 31 includes the multi-plate type heat exchange section 311.

[0105] Fig. 18 is a schematic perspective view showing the configuration of the heat exchanger 321 included in the lubricant cooler 32. In Fig. 18, the solid arrow P3 indicates the flow of the coolant that cools the engine block, and the dashed arrow P4 indicates the flow of the lubricant. As shown in Fig. 18, the heat exchanger 321 of the lubricant cooler 32 has, on its rear surface, a lubricant cooler coolant inlet 3211 that serves as an inlet for the coolant (fresh water), and a lubricant cooler coolant outlet 3212 that serves as an outlet for the coolant. The heat exchanger 321 also has, on its rear surface, a lubricant inlet 3213 that serves as an inlet for the lubricant, and a lubricant outlet 3214 that serves as an outlet for the lubricant.

[0106] The heat exchanger 321 of the lubricant cooler 32 is also a so-called multi-plate type heat exchanger, similar to the coolant cooler 31. That is, the lubricant cooler 32 includes a multi-plate type heat exchanger 321. The heat exchanger 321 has a plurality of plates stacked in the front-rear direction. The type of liquid flowing between the plates alternates. For example, the type of liquid flowing between the two plates alternates from the rear to the front as follows: coolant (fresh water), lubricant, coolant, lubricant, etc. This configuration allows efficient heat exchange between the coolant and the lubricant.

[0107] In this embodiment, the cooling liquid for the lubricant oil cooler 32 is fresh water, but if fresh water is the first cooling liquid, the cooling liquid for the lubricant oil cooler 32 may be a second cooling liquid such as seawater that is different from the first cooling liquid.

[0108] The multi-plate heat exchange units 311, 321 can adjust the length and width of each plate or the number of plates according to the required cooling capacity. For this reason, the coolant cooler 31 and the lubricant cooler 32 are configured to have a multi-plate heat exchange unit, which makes it easier to arrange the coolant cooler 31 and the lubricant cooler 32 side by side on the same surface. The heat exchange units 311, 321 may have a configuration other than the multi-plate type, such as a multi-tube type. The heat exchange unit 311 of the coolant cooler 31 and the heat exchange unit 321 of the lubricant cooler 32 may be configured in a different manner from each other.

[0109] <4. Things to keep in mind> Various technical features disclosed in this specification can be modified in various ways without departing from the spirit of the technical creation. In other words, the above embodiment should be considered to be illustrative in all respects and not restrictive. In addition, multiple embodiments and modifications shown in this specification may be combined to the extent possible.

[0110] In the embodiment described above, the engine 100 is a V-type engine, but this is merely an example. The present invention is also applicable to, for example, an in-line engine in which the pistons reciprocate vertically, or a horizontally opposed engine in which the pistons reciprocate horizontally. The present invention is suitable for an engine having multiple rows of cylinders extending in the crankshaft direction. [Explanation of symbols]

[0111] 1. Cylinder block (engine block) 4. Head block (engine block) 6. Crankshaft 31 Coolant cooler 32 Lubricant oil cooler 40 Gear case 100···Engine 111R: Right cylinder row 111L: Left cylinder row 311... Heat exchange section of coolant cooler 321...Heat exchange section of lubricating oil cooler 407R···Right cylinder row No. 1 case internal passage (case internal passage, No. 1 passage) 407L···First case passage for left cylinder row (case passage, first passage) 411... Common case internal flow path (case internal flow path, second flow path)

Claims

1. a coolant cooler that cools a first coolant that cools an engine block that is composed of a cylinder block and a cylinder head; a lubricant oil cooler that cools lubricant oil using the first coolant or the second coolant; a gear case disposed between the engine block and the coolant cooler and / or the lubricant oil cooler; Equipped with The cooling liquid cooler and the lubricating oil cooler are arranged side by side on one end side in the crankshaft direction, The engine, wherein the coolant cooler and / or the lubricant oil cooler is mounted to the gear case.

2. The engine of claim 1 , wherein at least one of the coolant cooler and the lubricant oil cooler includes a multiple plate heat exchanger.

3. The engine according to claim 1 or 2, wherein the gear case has an internal coolant flow path through which the first coolant flows.

4. The cooling liquid flow path in the case is a first flow path disposed upstream of the coolant cooler; a second flow path disposed downstream of the coolant cooler; The engine of claim 3 , comprising:

5. 5. An engine as claimed in any one of claims 1 to 4, comprising a plurality of rows of cylinders arranged alongside one another, each row extending in the crankshaft direction.

Images