Internal combustion engine and purification device

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 and a purification device for purifying exhaust gas.

Background Art

[0002] Techniques for purifying exhaust gas from an internal combustion engine of a vehicle using a purification device having a catalyst are known. When such a purification device is disposed at a position away from the internal combustion engine, the time until the catalyst reaches an activation temperature becomes longer when the internal combustion engine is started. For this reason, immediately after the internal combustion engine is started, the exhaust gas purification performance of such a purification device may not be sufficiently exhibited, and it may become difficult to cope with the recent tightening of exhaust gas regulations. On the other hand, as described in Patent Document 1, a technique of disposing a catalyst portion in an exhaust port of a combustion chamber of an internal combustion engine is known.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the technique disclosed in Patent Document 1, since the catalyst portion is located near the combustion chamber of the internal combustion engine, it is continuously exposed to high-temperature exhaust gas during the operation of the internal combustion engine. As a result, although the purification performance of the catalyst portion is improved, the catalyst metal supported on the catalyst may aggregate, and the purification performance of the catalyst portion may decrease.

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

Means for Solving the Problems

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

[0007] According to the above configuration, although the purification device is disposed in the exhaust passage provided in the main body portion of the internal combustion engine, it is cooled by the cooling portion. Therefore, a decrease in the purification performance of the purification device can be suppressed.

[0008] In one aspect of the present disclosure, a plurality of combustion chambers may be provided. As the exhaust passage, a plurality of first passages each connected to a respective combustion chamber and a second passage formed by combining these first passages into one may be provided. The purification device may be disposed in the second passage.

[0009] According to the above configuration, exhaust from a plurality of combustion chambers can be efficiently purified. In one aspect of the present disclosure, a plurality of combustion chambers and a plurality of purification devices may be provided. As the exhaust passage, a plurality of first passages each extending from a respective combustion chamber may be provided. Each purification device may be disposed in a respective first passage.

[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 portion may have a flow path for a refrigerant for cooling the internal combustion engine.

[0011] According to the above configuration, complication of the configuration due to addition of the cooling portion can be suppressed. In one aspect of the present disclosure, the cooling portion may have a flow path for a refrigerant for cooling a device other than the internal combustion engine mounted on the vehicle.

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

[0013] According to the above configuration, the purification member can be suitably cooled. One aspect of the present disclosure is a purification device provided in the above-described internal combustion engine. According to the above configuration, a decrease in the purification performance in the purification device can be suppressed.

Brief Description of the Drawings

[0014]

Figure 1

Figure 2

Figure 3

Modes for Carrying Out the Invention

[0015] Hereinafter, exemplary embodiments of the present disclosure will be described with reference to the drawings. [1. First Embodiment] [(1) Configuration of Internal Combustion Engine] The internal combustion engine 1 of the first embodiment is mounted on a vehicle and used as a power source for driving the vehicle (see FIGS. 1 and 2). Note that the vehicle includes various automobiles including motorcycles and four-wheel vehicles. Further, the internal combustion engine 1 may have various configurations, for example, a gasoline engine, a diesel engine, a two-stroke engine, a four-stroke engine, a rotary engine, etc. 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 portion 14, and a refrigerant flow path 15. Note that the number of cylinders 11 is three as an example, but this number can be determined as appropriate and may be, for example, one or more than three.

[0016] As an example, a reciprocating engine as shown in FIGS. 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 a cylinder 11 formed therein and houses a crankshaft and the like therein. Further, the cylinder head 10A is disposed on the upper portion of the cylinder block 10B and forms the top of each cylinder 11.

[0017] Each cylinder 11 has a cylindrical space in which a piston 11B is disposed inside, and a combustion chamber 11A is formed between the upper end of the piston 11B and the cylinder head 10A. Further, as an example, two exhaust valves 11C are provided in the combustion chamber 11A of each cylinder 11, and one intake valve (not shown) is provided. 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 appropriately determined.

[0018] The intake port 12 is provided inside the cylinder head 10A corresponding to each cylinder 11, and allows air supplied from an intake manifold (not shown) to flow into the combustion chamber 11A of the cylinder 11.

[0019] The exhaust port 13 is an exhaust passage provided inside the cylinder head 10A corresponding to each cylinder 11, and is connected to the combustion chamber 11A via two exhaust valves 11C provided in the cylinder 11. The exhaust port 13 is configured to allow the exhaust flowing out from each combustion chamber 11A via the exhaust valve 11C to flow downwards.

[0020] The collecting portion 14 is an exhaust passage formed by gathering a plurality of exhaust ports 13 into one, and is provided inside the cylinder head 10A. The exhaust from each exhaust port 13 flows into the exhaust collecting portion 14. That is, the first end of the collecting portion 14 is connected to the end of each exhaust port 13, and the plurality of exhaust ports 13 and the collecting portion 14 form an exhaust passage similar to an exhaust manifold. On the other hand, the second end of the collecting portion 14 forms an exhaust outlet 14A provided on the side surface of the cylinder head 10A, and the exhaust flowing down the collecting portion 14 flows out to the outside from the exhaust outlet 14A. Note that a pipe (not shown) is connected to the exhaust outlet 14A, and the exhaust flowing out from the exhaust outlet 14A is guided to the outside of the vehicle through the pipe.

[0021] The refrigerant passage 15 is a passage for the coolant for cooling the internal combustion engine 1, and is formed inside the cylinder head 10A and the cylinder block 10B. The refrigerant passage 15 has a water jacket 15A for cooling each cylinder 11. 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 is arranged in the collecting portion 14 in 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, and may be, for example, a catalyst. More specifically, the purification member 20 may be configured such that a catalyst substance 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 has a cylindrical shape (a cylindrical shape as an example), and first and second openings are formed at both ends. However, the case 21 is not limited thereto, and may be, for example, a member having a large number of holes that communicate the inside and the outside of the case 21.

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

[0026] When the exhaust gas flowing into the collecting part 14 reaches the purification member 20, it enters the inside of the case 21 through the first opening and is purified by the purification member 20. Then, the purified exhaust gas flows out of the case 21 through the second opening and further flows downward on the downstream side.

[0027] Also, although a part of the case 21 protrudes outside the internal combustion engine 1 from the collecting part 14, as an example, the position of the purification member 20 inside the case 21 is adjusted so as to be located inside the collecting part 14. That is, the purification member 20 is located inside the collecting part 14, in other words, inside the internal combustion engine 1. Of course, it is not limited to this, and the position of the purification member 20 inside the case 21 can be adjusted as appropriate.

[0028] [(3) Configuration of the refrigerant flow path] A part of the section of the refrigerant flow path 15 is configured as a cooling part 15B for cooling the purification device 2. That is, the cooling part 15B is arranged in the vicinity of the section (hereinafter referred to as the arrangement section) in the collecting part 14 where the purification device 2 is arranged (see FIGS. 1 and 2).

[0029] As an example, the cooling part 15B is located outside the collecting part 14 and is arranged so as to surround the outer peripheral surface of the arrangement section. That is, the cooling part 15B is arranged so as to face the part adjacent to the purification member 20 in the case 21. Also, the cooling part 15B is arranged so as to surround the purification member 20. Of course, it is not limited to this, and the cooling part 15B may be arranged inside the collecting part 14, and further, the cooling part 15B may be arranged inside the collecting part 14 so as to be in contact with the case 21 of the purification device 2.

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

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

[0032] [(2) Configuration of Exhaust Flow Path] The internal combustion engine 1 of the second embodiment is different from the first embodiment in that the collecting section 14 is not provided (see FIG. 3). Also in the second embodiment, each exhaust port 13 is provided inside the cylinder head 10A corresponding to each cylinder 11, and the first end thereof is connected to the combustion chamber 11A via two exhaust valves 11C, similar to the first embodiment. However, the second end of each exhaust port 13 forms an exhaust outlet 13A provided on the side surface of the cylinder head 10A, and the exhaust flowing down through each exhaust port 13 flows out to the outside from the exhaust outlet 13A. These exhaust outlets 13A are connected to a branch pipe in an exhaust manifold (not shown).

[0033] And the internal combustion engine 1 of the second embodiment includes a plurality of purification devices 2, and the purification device 2 is disposed at each exhaust port 13. As an example, the purification device 2 is disposed at the exhaust port 13 such that a part of the case 21 is located inside the exhaust port 13 and the remaining part protrudes outside from the exhaust outlet 13A of the cylinder head 10A. That is, the purification device 2 covers the exhaust outlet 13A and is disposed such that a part thereof protrudes from the exhaust port 13. Of course, the present invention is not limited to this, and the purification device 2 may be disposed such that the entire case 21 is located inside the exhaust port 13, or may be disposed at a position away from the exhaust outlet 13A inside the exhaust port 13.

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

[0035] Also, in each purification device 2, as an example, similar to the first embodiment, the position of the purification member 20 in the case 21 is adjusted so as to be located inside the collecting portion 14. Of course, the present invention is not limited to this, and the position of the purification member 20 in the case 21 can be adjusted as appropriate.

[0036] [(3) Configuration of Refrigerant Flow Path] Also in the second embodiment, the internal combustion engine 1 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, the internal combustion engine 1 of the second embodiment cools the purification device 2 by a second refrigerant flow path 17 provided separately from the first refrigerant flow path 16.

[0037] The second refrigerant flow path 17 is configured as a cooling unit that cools the purification device 2, and is disposed near the section (hereinafter referred to as the "disposal section") where the purification device 2 is disposed at each exhaust port 13. As an example, the second refrigerant flow path 17 is located outside each exhaust port 13 and is disposed so as to surround the outer peripheral surface of the disposal section. That is, the second refrigerant flow path 17 (in other words, the cooling unit) is disposed so as to face the portion adjacent to the purification member 20 in the case 21. Further, the second refrigerant flow path 17 is disposed so as to surround the purification member 20. Of course, the present invention is not limited thereto, and the second refrigerant flow path 17 may be disposed inside each exhaust port 13, or may be disposed inside each exhaust port 13 so as to abut against the case 21 of the purification device 2.

[0038] Refrigerant flows down in the second refrigerant flow path 17 for cooling a device other than the internal combustion engine 1 mounted on the vehicle. As an example, the device may be an air conditioner of the vehicle, and the refrigerant gas of the air conditioner may circulate 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 from the refrigerant flow path of the air conditioner.

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

[0040] [(4) Modification Example] The internal combustion engine 1 of the second embodiment may be provided with a plurality of exhaust ports 13 and a collecting portion 14 in the same manner as in the first embodiment. And similarly, the purification device 2 may be disposed at each exhaust port 13.

[0041] [3. Effects] (1) According to the above embodiment, since the purification device 2 is provided inside the internal combustion engine 1, the distance between the purification device 2 and the combustion chamber 11A is shortened. Therefore, exhaust gas at a higher temperature passes through the purification member 20, and it becomes easier to raise the temperature of the purification member 20 at the start of the internal combustion engine 1 without separately providing a heating device such as an electric heater. Accordingly, it is possible to suppress deterioration of fuel consumption, increase in cost, etc., reduce the weight of the vehicle, reduce the number of parts, and reduce the CO2 emissions during manufacturing, while shortening the time until the purification member 20 reaches the activation temperature.

[0042] In addition, since the purification member 20 is exposed to high-temperature exhaust gas, sintering may occur in which the catalytic metal in the purification member 20 aggregates, and there is a risk that the purification performance of the purification member 20 may deteriorate due to a decrease in the contact area between the exhaust gas and the catalytic metal. On the other hand, according to the above embodiment, the purification device 2 is cooled by the cooling unit 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] In addition, the internal combustion engine 1 contains a large amount of metal material, has a large heat capacity as a whole, and is difficult to cool down even after the operation stops. Therefore, even after the internal combustion engine 1 stops, the cooling of the purification member 20 is suppressed, and as a result, the time until the purification member 20 reaches the activation temperature can be shortened at the restart of the internal combustion engine 1.

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

[0045] (4) Also, in the first embodiment, the purification device 2 is cooled by the coolant for cooling the internal combustion engine 1. Therefore, while utilizing a conventionally used configuration, the purification device 2 provided inside the internal combustion engine 1 can be cooled. Accordingly, reliability can be ensured, and the complication of the configuration due to adding a cooling part can be suppressed. As a result, the manufacturing cost can be suppressed, and the CO2 emissions during manufacturing can be reduced.

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

[0047] (6) Also, in the first and second embodiments, the cooling part is arranged so as to face a portion adjacent to the purification member 20 in the case 21. Therefore, the purification member 20 can be suitably cooled.

[0048] [4. Other Embodiments] (1) In the first and second embodiments, the purification device 2 is arranged at the exhaust port 13 or the collecting part 14 provided in the cylinder head 10A of the internal combustion engine 1. However, not limited to this, in the cylinder block 10B of the internal combustion engine 1, a plurality of exhaust flow paths (in other words, the first flow paths) connected to each exhaust port 13 and an exhaust flow path (in other words, the second flow path) formed by these first flow paths being combined into one may be provided. Further, an outlet of the second flow path may be provided in the cylinder block 10B. And, similar to the first embodiment, the purification device 2 may be arranged in the second flow path, or the purification device 2 may be arranged in each first flow path.

[0049] Also, a plurality of first flow paths may be provided without providing a collecting part in the cylinder block 10B, and the outlets of each first flow path may be provided in the cylinder block 10B. And, similar to the second embodiment, the purification device 2 may be arranged in each second flow path.

[0050] (2) In the internal combustion engine 1 of the first embodiment, in the same manner as in 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, in the same manner as in the second embodiment, the purification device 2 may be cooled by flowing a refrigerant for cooling devices other than the internal combustion engine 1 in the second cooling flow path.

[0051] Further, in the internal combustion engine 1 of the second embodiment, in the same manner as in the first embodiment, a refrigerant flow path through which the coolant of the internal combustion engine 1 flows may be arranged near the purification device, and the purification device 2 may be cooled by the coolant flowing through the refrigerant flow path.

[0052] Further, 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 instead of the refrigerant used for cooling devices other than the purification device 2.

[0053] (3) A plurality of functions of one component in the above embodiments may be realized by a plurality of components, or one function of one component may be realized by a plurality of components. Also, a plurality of functions of a plurality of components may be realized by one component, or one function realized by a plurality of components may be realized by one component. Further, a part of the configuration of the above embodiments may be omitted. Also, at least a part of the configuration of the above embodiments may be added to or replaced with the configuration of other above embodiments.

[0054] [7. Technical Idea Disclosed in this Specification] [Item 1] An internal combustion engine for a vehicle, having at least one combustion chamber, a main body portion provided therein with the combustion chamber and an exhaust flow path configured to allow exhaust flowing out from the combustion chamber to flow down, at least one purification device arranged in the exhaust flow path of the main body portion, a cooling portion configured to cool the purification device, and comprising, The purification device is, a purification member configured to purify the exhaust gas, a case that houses the purification member, and an internal combustion engine including these.

[0055] [Item 2] The internal combustion engine according to Item 1, including a plurality of the combustion chambers, wherein as the exhaust gas flow path, a plurality of first flow paths each connected to a respective one of the combustion chambers and a second flow path formed by combining these first flow paths into one are provided, and the purification device is disposed in the second flow path Internal combustion engine.

[0056] [Item 3] The internal combustion engine according to Item 1, including a plurality of the combustion chambers and a plurality of the purification devices, wherein as the exhaust gas flow path, a plurality of first flow paths each extending from a respective one of the combustion chambers are provided, and each of the purification devices is disposed in a respective one of the first flow paths Internal combustion engine.

[0057] [Item 4] The internal combustion engine according to any one of Items 1 to 3, wherein the cooling unit has a flow path for a refrigerant 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, wherein the cooling unit has a flow path for a refrigerant for cooling a device other than the internal combustion engine mounted on the vehicle Internal combustion engine.

[0059] [Item 6] The internal combustion engine according to any one of Items 1 to 5, The cooling unit is arranged 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. Corresponding relationships of expressions] The exhaust port 13 corresponds to an example of the first flow path, and the collecting portion 14 corresponds to an example of the second flow path.

Explanation of reference numerals

[0061] 1... Internal combustion engine, 10... Main body portion, 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 portion, 14A... Exhaust outlet, 15... Refrigerant flow path, 15A... Water jacket, 15B... Cooling unit, 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 having the combustion chamber and an exhaust flow path configured to flow exhaust gas flowing out from the combustion chamber downward; At least one purification device disposed in the exhaust flow path of the main body; A cooling section configured to cool the purification device; Equipped with The purification device includes: A purification member configured to purify the exhaust gas; a case that houses the purification member; An internal combustion engine comprising:

2. 2. The internal combustion engine according to claim 1, A plurality of the combustion chambers are provided, As the exhaust flow passage, a plurality of first flow passages connected to the respective combustion chambers and a second flow passage formed by combining the first flow passages into one are provided, 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 section 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.

7. A purification device provided in the internal combustion engine according to any one of claims 1 to 3.

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