JP4039152B2 - Engine exhaust system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an engine exhaust system capable of suitably collecting exhaust heat.
[0002]
[Prior art]
An example of a configuration of an engine that is downsized is disclosed in, for example, Japanese Patent Laid-Open No. 9-264155, and an exhaust manifold extending from a combustion chamber of each cylinder is curved in a substantially L shape and falls downward. It has become. An exhaust pipe is connected to the gathering portion where the tips of the exhaust manifolds gather, and the exhaust pipe is disposed outside the cylinder block along each cylinder (cylinder bore) formed in the cylinder block. It has become a state.
[0003]
[Problems to be solved by the invention]
Therefore, since the exhaust manifold is arranged at a position away from the cylinder block in this way, in order to effectively recover the exhaust heat introduced to the exhaust manifold when starting the engine in winter, the cylinder block and the exhaust It is necessary to separately provide a heat recovery piping member or the like between the manifold.
[0004]
The present invention has been made to solve such problems, and the object thereof is to be led to the exhaust manifold without providing a separate piping member for heat recovery even when the engine is downsized. Another object of the present invention is to provide an engine exhaust system capable of recovering exhaust heat.
[0005]
[Means for Solving the Problems]
Accordingly, an engine exhaust system according to a first aspect of the present invention is an engine exhaust system in which a cylinder block and a cylinder head are abutted and integrated with each other. The engine exhaust system is adjacent to the cylinder portion and the cylinder portion. An exhaust gas circulation part that circulates the exhaust gas after combustion flowing in from the cylinder, and a heat exchange part that is arranged around the cylinder part and the exhaust gas circulation part, and exchanges heat between the cylinder part and the exhaust gas circulation part. It is integrally formed on the block body side , and the heat exchange part is not opened outside the exhaust circulation part on the abutting surface with the cylinder head of the cylinder block, but only on the periphery in contact with the cylinder part. Features.
[0006]
By integrally forming a heat exchanging part for exchanging heat between the cylinder part and the exhaust circulation part on the main body side of the cylinder block, the exhaust gas obtained from the exhaust circulation part can be obtained without providing a separate pipe for heat exchange. Heat can be recovered.
[0007]
An engine exhaust system according to a second aspect is the engine exhaust system according to the first aspect, wherein the cylinder block has openings of the cylinder portion and the exhaust circulation portion formed on the abutting surface with the cylinder head. And
[0008]
With this configuration, when the cylinder block and the cylinder head are assembled, a series of exhaust circulation portions that communicate between the cylinder head and the cylinder block is formed.
[0009]
The engine exhaust system according to a third aspect is the engine exhaust system according to the first or second aspect, wherein a plate-like gasket is interposed in an assembly portion between the cylinder block and the cylinder head. It has both the opening part corresponding to a cylinder part, and the opening part corresponding to an exhaust_gas | exhaustion distribution | circulation part, It is characterized by the above-mentioned.
[0010]
By configuring the gasket in this way, the gasket corresponding to the cylinder portion and the gasket corresponding to the exhaust circulation portion can be configured by one common gasket.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.
[0012]
1 and 2 show an engine block according to an embodiment, and a vehicle four-cylinder engine having four cylinders is shown as an example.
[0013]
The engine E is integrally fixed with a later-described head gasket interposed between the cylinder block 100 and the cylinder head 200.
[0014]
The cylinder head 200 is integrally cast with an intake manifold 212 that guides intake air and an exhaust manifold 214 that guides exhaust gas. An intake port 216 is provided at one end of the intake manifold 212, and an exhaust manifold 214 is provided at one end of the exhaust manifold 214. Exhaust ports 218 are respectively formed.
[0015]
The intake port 216 includes an intake valve 220 that opens and closes the intake port 216, and the exhaust port 218 includes an exhaust valve 222 that opens and closes the exhaust port 216. The intake valve 220 and the exhaust valve 222 are constantly urged toward the cams 224 and 226 by a valve lifter having a spring, respectively, and the cams 224 and 226 attached to the camshaft rotate, The valve 220 and the exhaust valve 222 are configured to move forward and backward.
[0016]
In addition, on the abutting surface of the cylinder head 200 with the cylinder block 100, an opening in which the intake port 216 and the exhaust port 218 are formed in the recess, or cooling water flowing between the cylinder head 200 and the cylinder block 100 is provided. An opening of the exhaust manifold 214 is formed along with an opening of the passage (water jacket), an opening of the oil passage, and the like. The exhaust manifold 214 extends from the exhaust port 218 in the cylinder head 200 and is formed in a substantially L-shaped curve toward the cylinder block 200, and its open end is the cylinder block 100 in the cylinder head 200. And is formed on the butting surface.
[0017]
On the other hand, in the cylinder block 100, a cylindrical cylinder portion 100 that constitutes each cylinder, a crankcase upper portion 112, an exhaust manifold 130 described later, and the like are integrally cast, and at the lower end of the crankcase upper portion 112, A crankcase lower portion 114 that is separate from the crankcase upper portion 112 is connected, and the crankshaft 120 is sandwiched and supported by the crankcase upper portion 112 and the crankcase lower portion 114 from both sides. Further, the crankcase lower portion 114 is further provided with an oil pan 116 for storing lubricating oil. Each cylinder part 110 is formed at a position facing the intake port 210 and the exhaust port 212 of the cylinder head 200.
[0018]
The cylinder part 110 has a piston 118 slidably disposed therein, the piston 118 and the crankshaft 120 are connected via a connecting rod 122, and the vertical movement of the piston 118 is caused by the connecting rod. This is transmitted as a rotational driving force of the crankshaft 120 via 122.
[0019]
In FIG. 1, an axis indicating the center of the cylinder part 110 is indicated as L1, and a line passing through the rotation center line of the crankshaft 120 and parallel to the axis L1 is indicated as L2. As shown in the figure, a line L2 indicating the axial position of the crankshaft 120 is arranged so as to be offset by a distance d toward the intake manifold 212 with respect to the axial line L1 of the cylinder portion 110, whereby the first half of the expansion stroke. The piston speed can be set to be slow, and this action improves the thermal efficiency and increases the effective work amount, so that the fuel consumption can be improved.
[0020]
Further, an exhaust manifold 130 is formed adjacent to the cylinder portion 110 in the cylinder block 100 so as to follow the axis L1 of the cylinder portion 100. The exhaust manifold 130 is connected in series with an exhaust manifold 214 formed in the cylinder head 200 at the abutting surface between the cylinder head 200 and the cylinder block 100.
[0021]
FIG. 2 shows the abutting surface with the cylinder head 200 in the cylinder block 100, and the exhaust manifold 130 is formed corresponding to each cylinder part 110. The individual exhaust manifolds 130 formed along the cylinder portions 110 are integrally cast in the cylinder block 100 as a shape that gradually gathers toward the exhaust pipe 300 side. In the vicinity of the end portion 130 </ b> A that protrudes outwardly, and is connected to the exhaust pipe 300.
[0022]
Further, a water jacket 140 as a cooling water passage is formed in the cylinder block 100 so as to surround the cylinder bore 110 </ b> A forming each cylinder part 110. The water jacket 140 further extends so as to surround the exhaust manifold 130, thereby forming a series of cooling water passages surrounding the cylinder portions 110 and the exhaust manifolds 130.
[0023]
The water jacket 140 is open to the butting surface in the vicinity of the cylinder portion 110, but in the vicinity of the exhaust manifold 130, which is the outer edge portion of the cylinder block 100, from the viewpoint of sufficiently preventing water leakage. It is formed on the inner side of the cylinder block 100 without opening in the surface, and this state is indicated by a dotted line in FIG.
[0024]
In FIG. 2, reference numeral 150 is a bolt hole when the cylinder block 100 and the cylinder head 200 are fastened with bolts, and reference numeral 152 is an oil passage through which oil flows.
[0025]
As described above, the exhaust manifold 130 is formed in the vicinity of the cylinder portion 110 in the cylinder block 100, and the water jacket 140 is provided around the cylinder portion 110 and the exhaust manifold 130. The heat of the exhaust gas to be guided can be recovered in the water jacket 140 in the cylinder block 100 without the need for providing another pipe or the like. Therefore, the exhaust heat from the exhaust manifold 130 can be effectively used as a warm-up, particularly when starting the engine in winter.
[0026]
Further, the engine E configured as described above has a structure in which the axial position (the position indicated by the line L2) of the crankshaft 120 is offset toward the intake manifold 212 with respect to the axial line L1 of the cylinder portion 110 as described above. Therefore, it is possible to secure a space on the exhaust manifold 130 side that is the opposite side, and by using this space, the exhaust manifold is integrally formed on the cylinder block 100 side, so that a limited space can be obtained. It can be used effectively, and can contribute further by downsizing the engine.
[0027]
Further, by configuring the engine E in this way, the cylinder head gasket 400 interposed in the abutting surface (assembly portion) between the cylinder block 100 and the cylinder head 200 is formed as a single plate-like shape as shown in FIG. The cylinder head gasket 400 can be configured. The cylinder head gasket 400 has a combustion chamber hole 410 corresponding to the cylinder part 110, a manifold hole 420 corresponding to the exhaust manifold 130, and a water hole 430 for circulating cooling water formed at positions corresponding to the water jacket 140. An oil hole 440 through which oil flows, a bolt hole 450 corresponding to the bolt hole 150, and the like are formed.
[0028]
In the embodiment described above, the opening end of the exhaust manifold 214 on the cylinder head 200 side and the opening end of the exhaust manifold 130 on the cylinder block 100 side face each other along the abutting surface of the cylinder block 100 and the cylinder head 200. Although the configuration disposed at the position is illustrated, the configuration is not limited to this example. That is, the opening end of the cylinder part 110 formed in the cylinder block 100 and the opening end of the exhaust manifold 130 are preferably formed on the same surface as the butted surface. The open end can also be formed on a surface different from the abutting surface with the cylinder block 100.
[0029]
An example of this is schematically shown in FIG. The opening end 510 forming the cylinder portion in the cylinder block 500 and the opening end 520 forming the exhaust manifold are formed on the same surface, and the opening end 610 of the exhaust manifold in the cylinder head 600 is opened on the side surface of the cylinder head 600. I am letting. Then, the open ends 520 and 610 of the exhaust manifolds are connected by a short connection pipe 700 that forms a part of the exhaust manifold and is curved in an L shape. Even in such a configuration, the opening end 510 that forms the cylinder portion of the cylinder block 500 and the opening end 520 that forms the exhaust manifold are formed on the same plane. The cylinder head gasket 800 interposed therebetween can be configured as a single plate-like gasket as in the above-described embodiment.
[0030]
【The invention's effect】
As described above, the engine exhaust system according to each claim employs a configuration in which the heat exchanging portion that performs heat exchange with the exhaust circulation portion is integrally formed on the main body side of the cylinder block. For this reason, it is possible to recover the exhaust heat obtained from the exhaust circulation section without separately providing a heat exchanging pipe or the like, thereby further reducing the size of the engine.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an engine according to an embodiment.
FIG. 2 is a plan view showing an assembly surface of a cylinder block.
FIG. 3 is a plan view showing a cylinder head gasket.
FIG. 4 is a schematic diagram showing an engine exhaust system according to another embodiment.
[Explanation of symbols]
E ... Engine, 100 ... Cylinder block, 110 ... Cylinder part, 118 ... Piston, 120 ... Crankshaft, 130 ... Exhaust manifold (exhaust flow part), 140 ... Water jacket (heat exchange part), 200 ... Cylinder head, 212 ... intake manifold, 214 ... exhaust manifold, 300 ... exhaust pipe, 400 ... cylinder head gasket, 410 ... combustion chamber hole, 420 ... manifold hole, 430 ... water hole, 440 ... oil hole, 450 ... bolt hole, 500 ... cylinder block , 510, 520 ... Open end, 600 ... Cylinder head, 610 ... Open end, 700 ... Connection pipe, 800 ... Cylinder head gasket

Claims (3)

An exhaust system for an engine in which a cylinder block and a cylinder head are butted and integrated,
A cylinder part that accommodates a piston, an exhaust gas circulation part that is adjacent to the cylinder part and that circulates the exhaust gas after combustion flowing in from the cylinder head side, and is disposed around the cylinder part and the exhaust gas circulation part. a heat exchange section for exchanging heat between the parts and exhaust flow portion, is formed integrally with the main body of the cylinder block,
The engine is characterized in that the heat exchanging portion is not opened outside the exhaust circulation portion, but is opened only around the cylinder portion on the abutting surface of the cylinder block with the cylinder head. Exhaust system.   The engine exhaust system according to claim 1, wherein the cylinder block is formed with openings of the cylinder part and the exhaust circulation part on a butt surface with the cylinder head.   A plate-like gasket is interposed in the assembly part of the cylinder block and the cylinder head, and the gasket includes both an opening corresponding to the cylinder part and an opening corresponding to the exhaust circulation part. The engine exhaust system according to claim 1 or 2, characterized in that

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