internal combustion engine

Abstract

To suppress deterioration of purification performance in a purification device of exhaust gas.SOLUTION: An internal combustion engine includes at least one combustion chamber, a body, at least one purification device, and a cooling unit. The body is internally provided with the combustion chamber, and an exhaust flow passage which allows exhaust gas flowing out of the combustion chamber to flow down. The purification device is disposed in the exhaust flow passage of the body. The cooling unit cools the purification device. The purification device includes a purification member and a case. The purification member purifies the exhaust gas. The case accommodates the purification member.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to an internal combustion engine to Regarding. [Background technology]

[0002] There is a known technology for purifying exhaust gas from a vehicle's internal combustion engine using a purification device with a catalyst. If such a purification device is located far from the internal combustion engine, it takes a long time for the catalyst to reach an activating temperature when the engine is started. This means that the purification device may not be able to fully purify exhaust gas immediately after the engine is started, which could make it difficult to comply with the increasingly strict exhaust gas regulations of recent years. In response to this issue, a technology is known in which a catalyst unit is located in the exhaust port of the combustion chamber of the internal combustion engine, as described in Patent Document 1. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-241523 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the technology disclosed in Patent Document 1, the catalyst section is located near the combustion chamber of the internal combustion engine, and is therefore continuously exposed to high-temperature exhaust gas while the internal combustion engine is running. While this improves the purification performance of the catalyst section, it can also cause the catalytic metal supported on the catalyst to aggregate, which can reduce the purification performance of the catalyst section.

[0005] In one aspect of the present disclosure, it is desirable to suppress a decrease in purification performance in an exhaust purification device. [Means for solving the problem]

[0006] One aspect of the present disclosure is an internal combustion engine for a vehicle, comprising at least one combustion chamber, a main body, at least one purification device, and a cooling unit. The main body has therein a combustion chamber and an exhaust flow path configured to allow exhaust gas flowing out of the combustion chamber to flow downward. The purification device is disposed in the exhaust flow path of the main body. The cooling unit is configured to cool the purification device. The purification device comprises a purification member and a case. The purification member is configured to purify the exhaust gas. The case houses the purification member.

[0007] According to the above configuration, although the purifying device is disposed in the exhaust flow path provided in the main body of the internal combustion engine, it is cooled by the cooling unit, which makes it possible to suppress a decrease in the purifying performance of the purifying device.

[0008] In one aspect of the present disclosure, a plurality of combustion chambers may be provided. The exhaust flow path may include a plurality of first flow paths connected to the respective combustion chambers, and a second flow path formed by combining the first flow paths. The purification device may be disposed in the second flow path.

[0009] According to the above configuration, exhaust gas from a plurality of combustion chambers can be efficiently purified. In one aspect of the present disclosure, the engine may include a plurality of combustion chambers and a plurality of purification devices. A plurality of first flow paths may be provided as exhaust flow paths, each extending from each combustion chamber. Each purification device may be disposed in each of the first flow paths.

[0010] According to the above configuration, the purification device can be disposed inside the internal combustion engine. In one aspect of the present disclosure, the cooling section may have a flow path for a coolant for cooling the internal combustion engine.

[0011] According to the above configuration, it is possible to prevent the configuration from becoming complicated due to the addition of the cooling unit. In one aspect of the present disclosure, the cooling section may have a flow path for a coolant for cooling a device other than an internal combustion engine mounted on a vehicle.

[0012] According to the above configuration, the purifier can be cooled efficiently. In one aspect of the present disclosure, the cooling portion may be disposed so as to face a portion of the case adjacent to the purification member.

[0013] According to the above configuration, the purification member can be cooled appropriately. One aspect of the present disclosure is a purification device that is provided in the above-described internal combustion engine. According to the above configuration, it is possible to suppress a decrease in the purification performance of the purification device. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is an explanatory view transparently showing the configuration of the periphery of a combustion chamber when the internal combustion engine of the first embodiment is viewed from above. FIG. [Figure 2] 1 is an explanatory view showing a transparent view of the configuration of the periphery of a combustion chamber when the internal combustion engine of the first embodiment is viewed from the side. FIG. [Figure 3] FIG. 10 is an explanatory view transparently showing the configuration of the periphery of a combustion chamber when an internal combustion engine according to a second embodiment is viewed from above. DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, exemplary embodiments of the present disclosure will be described with reference to the drawings. [1. First embodiment] [(1) Structure of the internal combustion engine] The internal combustion engine 1 of the first embodiment is mounted on a vehicle and used as a power source for propelling the vehicle (see FIGS. 1 and 2). Note that the vehicle includes various automobiles, including two-wheeled and four-wheeled vehicles. The internal combustion engine 1 may have various configurations, such as a gasoline engine, a diesel engine, a two-stroke engine, a four-stroke engine, or a rotary engine. The internal combustion engine 1 includes a main body 10, a plurality of cylinders 11, a plurality of intake ports 12, a plurality of exhaust ports 13, a collecting section 14, and a refrigerant flow path 15. Note that the number of cylinders 11 is three in one example, but the number can be determined as appropriate and may be one or more than three, for example.

[0016] As an example, a reciprocating engine as shown in Figures 1 to 3 will be described. The main body 10 has a cylinder head 10A and a cylinder block 10B. The cylinder block 10B has cylinders 11 formed therein and accommodates a crankshaft and other components therein. The cylinder head 10A is disposed on top of the cylinder block 10B and forms the top of each cylinder 11.

[0017] Each cylinder 11 is a cylindrical space in which a piston 11B is disposed, and a combustion chamber 11A is formed between the upper end of the piston 11B and the cylinder head 10A. The combustion chamber 11A of each cylinder 11 is provided with, for example, two exhaust valves 11C and one intake valve (not shown). Of course, the number of exhaust valves 11C and intake valves provided in each combustion chamber 11A is not limited to this and can be determined as appropriate.

[0018] The intake ports 12 are provided inside the cylinder head 10A corresponding to the respective cylinders 11, and allow air supplied from an intake manifold (not shown) to flow into the combustion chambers 11A of the cylinders 11.

[0019] The exhaust ports 13 are exhaust flow paths provided inside the cylinder head 10A corresponding to each cylinder 11, and are connected to the combustion chambers 11A via two exhaust valves 11C provided in the cylinders 11. The exhaust ports 13 are configured to allow exhaust gas that flows out from each combustion chamber 11A via the exhaust valves 11C to flow downward.

[0020] The collecting section 14 is an exhaust flow path formed by combining multiple exhaust ports 13 into one, and is provided inside the cylinder head 10A. Exhaust from each exhaust port 13 flows into the exhaust collecting section 14. That is, a first end of the collecting section 14 is connected to an end of each exhaust port 13, and the multiple exhaust ports 13 and the collecting section 14 form an exhaust flow path similar to an exhaust manifold. Meanwhile, a second end of the collecting section 14 forms an exhaust outlet 14A provided on the side surface of the cylinder head 10A, and the exhaust that flows down the collecting section 14 flows out from the exhaust outlet 14A to the outside. A pipe (not shown) is connected to the exhaust outlet 14A, and the exhaust that flows out from the exhaust outlet 14A is guided to the outside of the vehicle via the pipe.

[0021] The refrigerant flow path 15 is a flow path for a coolant for cooling the internal combustion engine 1, and is formed inside the cylinder head 10A and the cylinder block 10B. The refrigerant flow path 15 has a water jacket 15A for cooling each cylinder 11, and as an example, the water jacket 15A is arranged so as to surround the side surface of each cylinder 11.

[0022] [(2) Configuration of the purification device] A purification device 2 configured to purify exhaust gas is disposed in the collection section 14 of the internal combustion engine 1 (see FIGS. 1 and 2). The purification device 2 includes a purification member 20 and a case 21.

[0023] The purification member 20 is a member configured to purify exhaust gas, and may be a catalyst, for example. More specifically, the purification member 20 may be configured such that a catalytic material such as platinum is supported on a carrier such as porous ceramics.

[0024] The case 21 is configured to accommodate the purification member 20 therein. As an example, the case 21 is tubular (for example, cylindrical) and has first and second openings formed at both ends. However, the case 21 is not limited to this, and may be, for example, a member having a number of holes that connect the inside and outside of the case 21.

[0025] As an example, the purification device 2 is disposed in the collecting part 14 so that a portion of the case 21 is located inside the collecting part 14 and the remaining portion protrudes to the outside from the exhaust outlet 14A of the cylinder head 10A. In other words, the purification device 2 is disposed so that it covers the exhaust outlet 14A and a portion of it protrudes from the collecting part 14. Of course, this is not limiting, and the purification device 2 may be disposed so that the entire case 21 is located inside the collecting part 14, or may be disposed at a position inside the collecting part 14 away from the exhaust outlet 14A.

[0026] When the exhaust gas that has flowed into the collecting section 14 reaches the purification member 20, it passes through the first opening and enters the inside of the case 21, and is purified by the purification member 20. Then, the purified exhaust gas passes through the second opening and flows out of the case 21, and further flows downstream.

[0027] Furthermore, a portion of the case 21 protrudes from the collecting portion 14 to the outside of the internal combustion engine 1, but as one example, the position of the purification member 20 within the case 21 is adjusted so that it is located inside the collecting portion 14. In other words, the purification member 20 is located inside the collecting portion 14, in other words, inside the internal combustion engine 1. Of course, this is not limiting, and the position of the purification member 20 within the case 21 can be adjusted as appropriate.

[0028] [(3) Coolant flow path configuration] A section of the refrigerant flow path 15 is configured as a cooling section 15B that cools the purifier 2. That is, the cooling section 15B is disposed near the section of the collecting section 14 where the purifier 2 is disposed (hereinafter referred to as the "disposition section") (see FIGS. 1 and 2).

[0029] As an example, the cooling unit 15B is located outside the collecting unit 14 and is arranged so as to surround the outer circumferential surface of the arrangement section. In other words, the cooling unit 15B is arranged so as to face the portion of the case 21 adjacent to the purification member 20. The cooling unit 15B is also arranged so as to surround the purification member 20. Of course, this is not a limitation, and the cooling unit 15B may be arranged inside the collecting unit 14, or further, the cooling unit 15B may be arranged inside the collecting unit 14 so as to abut against the case 21 of the purification device 2.

[0030] That is, the purification device 2 is cooled by the coolant that cools the internal combustion engine 1. The coolant is circulated through the refrigerant flow path 15 by a water pump (not shown) provided in the cylinder block 10B. The coolant cooled by a radiator (not shown) reaches the cooling section 15B, thereby cooling the purification device 2.

[0031] [2. Second Embodiment] [(1) Overview] The internal combustion engine 1 of the second embodiment differs from the second embodiment mainly in the configurations of the refrigerant flow path and the exhaust flow path, and the number of purification devices 2 installed (see FIG. 3). Below, differences between the internal combustion engine 1 of the second embodiment and the first embodiment will be described.

[0032] [(2) Exhaust flow path configuration] The internal combustion engine 1 of the second embodiment differs from the first embodiment in that it is not provided with a collection section 14 (see FIG. 3). In the second embodiment, as in the first embodiment, each exhaust port 13 is provided inside the cylinder head 10A corresponding to each cylinder 11, and a first end of each exhaust port 13 is connected to the combustion chamber 11A via two exhaust valves 11C. However, a second end of each exhaust port 13 forms an exhaust outlet 13A provided on the side surface of the cylinder head 10A, and exhaust that flows down each exhaust port 13 flows out from the exhaust outlet 13A to the outside. Note that these exhaust outlets 13A are connected to branch pipes in an exhaust manifold (not shown).

[0033] The internal combustion engine 1 of the second embodiment is equipped with a plurality of purification devices 2, and a purification device 2 is disposed in each exhaust port 13. As an example, the purification device 2 is disposed in the exhaust port 13 such that a portion of the case 21 is located inside the exhaust port 13 and the remaining portion protrudes to the outside from the exhaust outlet 13A of the cylinder head 10A. In other words, the purification device 2 is disposed so that it covers the exhaust outlet 13A and a portion of it protrudes from the exhaust port 13. Of course, this is not limiting, and the purification device 2 may be disposed so that the entire case 21 is located inside the exhaust port 13, or may be disposed in a position inside the exhaust port 13 away from the exhaust outlet 13A.

[0034] Therefore, when the exhaust gas flowing out from each combustion chamber 11A reaches the purification member 20, similar to the first embodiment, it enters the inside of the case 21 and is purified by the purification member 20. Then, the purified exhaust gas flows out of the case 21 and further flows downstream.

[0035] Furthermore, in each purification device 2, as in the first embodiment, for example, the position of the purification member 20 within the case 21 is adjusted so that it is located inside the collection section 14. Of course, this is not limiting, and the position of the purification member 20 within the case 21 can be adjusted as appropriate.

[0036] [(3) Coolant flow path configuration] In the second embodiment, the internal combustion engine 1 also includes a first refrigerant flow path 16 having a water jacket similar to that of the first embodiment, and is cooled by the coolant flowing down the first refrigerant flow path 16 (see FIG. 3). However, in the internal combustion engine 1 of the second embodiment, the purification device 2 is cooled by a second refrigerant flow path 17 that is provided separately from the first refrigerant flow path 16.

[0037] The second refrigerant flow path 17 is configured as a cooling section that cools the purifier 2, and is arranged near the section of each exhaust port 13 where the purifier 2 is arranged (hereinafter referred to as the arrangement section). As an example, the second refrigerant flow path 17 is located outside each exhaust port 13 and is arranged so as to surround the outer circumferential surface of the arrangement section. In other words, the second refrigerant flow path 17 (in other words, the cooling section) is arranged so as to face the portion of the case 21 adjacent to the purifier member 20. The second refrigerant flow path 17 is also arranged so as to surround the purifier member 20. Of course, this is not a limitation, and the second refrigerant flow path 17 may be arranged inside each exhaust port 13, or may be arranged inside each exhaust port 13 so as to abut against the case 21 of the purifier 2.

[0038] A refrigerant for cooling a device other than the internal combustion engine 1 mounted on the vehicle flows down through the second refrigerant flow path 17. As an example, the device may be an air conditioner of the vehicle, and refrigerant gas of the air conditioner may be circulated through the second refrigerant flow path 17. In this case, the refrigerant gas of the air conditioner may be supplied from a flow path branched off from the refrigerant flow path of the air conditioner.

[0039] The refrigerant inlet 17A and refrigerant outlet 17B of the second refrigerant flow path 17 are provided, for example, on a side surface of the cylinder block 10B. Then, for example, a pump (not shown) or the like allows refrigerant from another device to flow in through the refrigerant inlet 17A, flow down the second refrigerant flow path 17, and then flow out through the refrigerant outlet 17B to the outside. This cools the purification devices 2 arranged in each exhaust port 13.

[0040] [(4) Modification] The internal combustion engine 1 of the second embodiment may be provided with a plurality of exhaust ports 13 and a collection section 14, similarly to the first embodiment. Similarly, a purification device 2 may be disposed in each exhaust port 13.

[0041] [3.Effects] (1) According to the above embodiment, the purification device 2 is provided inside the internal combustion engine 1, thereby shortening the distance between the purification device 2 and the combustion chamber 11A. This allows higher temperature exhaust gas to pass through the purification member 20, making it easier to increase the temperature of the purification member 20 when starting the internal combustion engine 1, without the need for a separate heating device such as an electric heater. This makes it possible to reduce the time it takes for the purification member 20 to reach an activation temperature while suppressing deterioration in fuel economy and increases in costs, reducing the vehicle weight, reducing the number of parts, and reducing CO2 emissions during manufacturing.

[0042] Furthermore, when the purification member 20 is exposed to high-temperature exhaust gas, sintering occurs, in which the catalytic metal in the purification member 20 aggregates, and the contact area between the exhaust gas and the catalytic metal decreases, which may result in a decrease in the purification performance of the purification member 20. In contrast, according to the above embodiment, the purification device 2 is cooled by the cooling section 15B or the second refrigerant flow path 17. Therefore, it is possible to suppress a decrease in the purification performance of the purification device 2.

[0043] Furthermore, the internal combustion engine 1 contains a large amount of metal material, has a large overall heat capacity, and is difficult to cool down even after stopping operation. Therefore, cooling of the purification member 20 is suppressed even after stopping the internal combustion engine 1, and as a result, when restarting the internal combustion engine 1, the time required for the purification member 20 to reach a temperature at which it is activated can be shortened.

[0044] (2) In the first embodiment, the purification device 2 is disposed in the collection section 14. Therefore, the exhaust gas flowing out from each combustion chamber 11A can be purified efficiently. (3) In the second embodiment, the purification device 2 is disposed in each exhaust port 13. Therefore, even if the collection section 14 is not provided inside the internal combustion engine 1, the purification device 2 can be disposed inside the internal combustion engine 1.

[0045] (4) In addition, in the first embodiment, the purification device 2 is cooled by the coolant used to cool the internal combustion engine 1. Therefore, the purification device 2 provided inside the internal combustion engine 1 can be cooled while utilizing a conventional configuration. Therefore, reliability can be ensured and the complexity of the configuration due to the addition of a cooling unit can be suppressed, resulting in reduced manufacturing costs and reduced CO2 emissions during manufacturing.

[0046] (5) In the second embodiment, the purifier 2 is cooled using the refrigerant for cooling devices other than the internal combustion engine 1 mounted on the vehicle. Therefore, the purifier 2 can be cooled efficiently.

[0047] (6) In the first and second embodiments, the cooling section is disposed so as to face the portion of the case 21 adjacent to the purification member 20. Therefore, the purification member 20 can be cooled appropriately.

[0048] 4. Other Embodiments (1) In the first and second embodiments, the purification device 2 is disposed in the exhaust port 13 or the collecting portion 14 provided in the cylinder head 10A of the internal combustion engine 1. However, this is not limiting, and the cylinder block 10B of the internal combustion engine 1 may be provided with a plurality of exhaust flow paths (in other words, first flow paths) connected to each exhaust port 13, and an exhaust flow path formed by combining these first flow paths (in other words, second flow path). Furthermore, an outlet of the second flow path may be provided in the cylinder block 10B. Then, the purification device 2 may be disposed in the second flow path as in the first embodiment, or a purification device 2 may be disposed in each first flow path.

[0049] Alternatively, multiple first flow paths may be provided without providing a collection section in the cylinder block 10B, and the outlets of each first flow path may be provided in the cylinder block 10B. Then, similar to the second embodiment, a purification device 2 may be disposed in each second flow path.

[0050] (2) In the internal combustion engine 1 of the first embodiment, similarly to the second embodiment, a first refrigerant flow path for cooling the internal combustion engine 1 and a second cooling flow path for cooling the purification device 2 may be provided. Then, similarly to the second embodiment, the purification device 2 may be cooled by causing a refrigerant for cooling devices other than the internal combustion engine 1 to flow down the second cooling flow path.

[0051] Furthermore, in the internal combustion engine 1 of the second embodiment, similarly to the first embodiment, a refrigerant flow path through which the cooling liquid of the internal combustion engine 1 flows may be arranged near the purification device, and the purification device 2 may be cooled by the cooling liquid flowing down the refrigerant flow path.

[0052] Furthermore, in the internal combustion engine 1 of the first and second embodiments, the purification device 2 may be cooled using a refrigerant provided exclusively for cooling the purification device 2, rather than a refrigerant used to cool devices other than the purification device 2.

[0053] (3) Multiple functions of one component in the above embodiments may be realized by multiple components, or one function of one component may be realized by multiple components. Also, multiple functions of multiple components may be realized by one component, or one function realized by multiple components may be realized by one component. Also, part of the configuration of the above embodiments may be omitted. Also, at least part of the configuration of the above embodiments may be added to or substituted for the configuration of another of the above embodiments.

[0054] [7. Technical Ideas Disclosed in the Present Specification] [Item 1] An internal combustion engine of a vehicle, at least one combustion chamber; a main body portion provided therein with the combustion chamber and an exhaust flow path configured to allow exhaust gas flowing out from the combustion chamber to flow downward; at least one purification device disposed in the exhaust flow path of the main body; a cooling unit configured to cool the purification device; Equipped with The purification device is a purification member configured to purify the exhaust gas; a case that houses the purification member; An internal combustion engine comprising:

[0055] [Item 2] The internal combustion engine according to item 1, a plurality of the combustion chambers; The exhaust flow path includes a plurality of first flow paths connected to the respective combustion chambers, and a second flow path formed by combining the first flow paths, The purification device is disposed in the second flow path. Internal combustion engine.

[0056] [Item 3] The internal combustion engine according to item 1, A plurality of said combustion chambers; a plurality of the purification devices; As the exhaust flow path, a plurality of first flow paths are provided extending from each of the combustion chambers, Each of the purification devices is disposed in each of the first flow paths. Internal combustion engine.

[0057] [Item 4] The internal combustion engine according to any one of items 1 to 3, The cooling unit has a flow path for a coolant for cooling the internal combustion engine. Internal combustion engine.

[0058] [Item 5] The internal combustion engine according to any one of items 1 to 3, The cooling unit has a flow path for a coolant for cooling devices other than the internal combustion engine mounted on the vehicle. Internal combustion engine.

[0059] [Item 6] An internal combustion engine according to any one of items 1 to 5, The cooling portion is disposed so as to face a portion of the case adjacent to the purification member. Internal combustion engine.

[0060] [Item 7] A purification device provided in the internal combustion engine according to any one of items 1 to 6. [8. Correspondence of Wording] The exhaust port 13 corresponds to an example of a first flow path, and the collecting portion 14 corresponds to an example of a second flow path. [Explanation of symbols]

[0061] 1...internal combustion engine, 10...main body, 10A...cylinder head, 10B...cylinder block, 11...cylinder, 11A...combustion chamber, 11B...piston, 11C...exhaust valve, 12...intake port, 13...exhaust port, 13A...exhaust outlet, 14...collecting section, 14A...exhaust outlet, 15...refrigerant flow path, 15A...water jacket, 15B...cooling section, 16...first refrigerant flow path, 17...second refrigerant flow path, 17A...refrigerant inlet, 17B...refrigerant outlet, 2...purification device, 20...purification member, 21...case

Claims

1. An internal combustion engine of a vehicle, at least one combustion chamber; a main body portion provided therein with the combustion chamber and an exhaust flow path configured to allow exhaust gas flowing out from the combustion chamber to flow downward; at least one purification device disposed in the exhaust flow path of the main body; a cooling unit configured to cool the purification device; Equipped with The purification device is a purification member configured to purify the exhaust gas; a case that houses the purification member; Equipped with the exhaust flow path has an exhaust outlet through which exhaust gas flows out from the main body portion to the outside, the purification device is disposed in the exhaust flow path with a portion of the case protruding from the exhaust outlet to the outside of the main body and the internal combustion engine, The purification member of the at least one purification device is located inside the main body. Internal combustion engine.

2. 2. The internal combustion engine according to claim 1, a plurality of the combustion chambers; The exhaust flow path includes a plurality of first flow paths connected to the respective combustion chambers, and a second flow path formed by combining the first flow paths, The purification device is disposed in the second flow path. Internal combustion engine.

3. 2. The internal combustion engine according to claim 1, A plurality of said combustion chambers; a plurality of the purification devices; As the exhaust flow passage, a plurality of first flow passages are provided extending from each of the combustion chambers, Each of the purification devices is disposed in each of the first flow paths. Internal combustion engine.

4. An internal combustion engine according to any one of claims 1 to 3, The cooling unit has a flow path for a coolant for cooling the internal combustion engine. Internal combustion engine.

5. An internal combustion engine according to any one of claims 1 to 3, The cooling unit has a flow path for a coolant for cooling devices other than the internal combustion engine mounted on the vehicle. Internal combustion engine.

6. An internal combustion engine according to any one of claims 1 to 3, The cooling portion is disposed so as to face a portion of the case adjacent to the purification member. Internal combustion engine.

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