JP2514559Y2 - Structure of cylinder block - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to the structure of a cylinder block, and in particular, facilitates sand removal of a core after casting, and facilitates confirmation of sand removal. The present invention relates to a structure of a cylinder block capable of avoiding the generation of extraneous material, making the wall thickness of a cylinder wall uniform, preventing deformation of a cylinder bore, and reducing the generation of noise to the outside.

[Conventional technology]

The internal combustion engine is configured by combining a cylinder block and a cylinder head.

As shown in FIGS. 8 and 9, the cylinder block 102 includes
A water jacket 112 is formed along the cylinder bore 104 from the head mating surface 106 to the deepest portion 110 at a depth not reaching the skirt portion (crank case) (108), and the head mating surface 106 penetrates into the skirt portion 108. Blow-by gas flow passage 114 formed along water jacket 112
And form.

The structure of the cylinder block is disclosed, for example, in Japanese Utility Model Laid-Open No. 62-71314. In the crankcase described in this publication, there is a swelling extending on the outer surface of the connecting portion between the crankcase and the cylinder portion and directly below the oil drop passage or the blow-by gas passage toward the joint surface to the cylinder head. In the bulging portion, the lower end of the oil drop passage and / or the blow-by gas passage is opened.

[Problems to be solved by the invention]

By the way, in the structure of the conventional cylinder block, as shown in FIGS.
However, from the cylinder head mating surface 106 to the inside of the skirt portion 108, they are formed to have substantially the same small passage sectional area.

Therefore, as shown in FIG. 10, the blow-by gas flow passage is
When 114 is formed with a certain small passage cross-sectional area, it is difficult to remove sand from the core after casting due to poor fluidity of the sand in the core, and sand from the bottom side of the skirt portion 108 It was difficult to confirm the drop.

Further, as shown in FIGS. 11 and 12, the blow-by gas flow passage is
114 is formed with a constant passage cross-sectional area, and the passage inner surface 104b of the cylinder wall 104a between the cylinder bores 104, 104 is formed.
Is formed by a mother die (ordinary sand) (indicated by arrow A), it is easy for the thin portion to be attached to the intermediate portion 116 between the cylinder bores 104, 104. There is a disadvantage that the cylinder bores 104, 104 are likely to be deformed due to the influence of heat at the time.

Further, as shown in FIG. 13, since the cylinder wall 104a of the sleeve portion below the water jacket 112 is in direct contact with the outside air, the internal noise is likely to leak to the outside, and a large noise is generated outside. However, there is a problem that the strength of the product decreases. Incidentally, in FIG. 13, reference numeral 118 is a piston.

[Purpose of device]

Therefore, an object of the present invention is to form a blow-by gas flow passage between adjacent cylinder bores and laterally in the vicinity of a cylinder head bolt boss in order to eliminate the above-mentioned inconvenience.
A first blow-by gas flow passage from the mating surface of the head to the deepest portion of the water jacket and a second blow-by gas flow passage that is in communication with the first blow-by gas flow passage and is below the deepest portion of the water jacket. And a second blow-by gas flow passage is formed in the column direction of the cylinder bore so that the second blow-by gas flow passage has a second cross-sectional area larger than that of the first blow-by gas flow passage. The first blow-by gas flow passage is formed wider than the first blow-by gas flow passage, and the first blow-by gas flow passage is formed laterally with respect to the center axis of the cylinder bore. Since the second passage wall is provided below the water jacket and overlaps with the cylinder wall, sand removal of the core is facilitated after casting. At the same time, it is possible to easily confirm that sand has fallen off.Also, it is possible to prevent the use of spoiled meat, form a uniform cylinder wall thickness, prevent deformation of the cylinder bore, and reduce the generation of noise to the outside. It is to realize the structure of the cylinder block.

[Means for solving problems]

To achieve this object, the present invention provides a water jacket formed along the cylinder bore to a depth that does not reach the skirt portion from the head mating surface, and the water jacket along the water jacket to penetrate from the head mating surface into the skirt portion. In the structure of the cylinder block having the formed blow-by gas flow passage, the blow-by gas flow passage is formed between the adjacent cylinder bores and laterally in the vicinity of the cylinder head bolt boss, and the blow-by gas flow passage is formed by the head alignment. A first blow-by gas flow passage extending from a surface to the deepest portion of the water jacket and a second blow-by gas flow passage communicating with the first blow-by gas flow passage and located below the deepest portion of the water jacket, The second passage cross-sectional area of the second blow-by gas flow passage is set to the first blow The second blow-by gas flow passage is formed wider than the first blow-by gas flow passage in the column direction of the cylinder bore so as to be formed larger than the first passage cross-sectional area of the gas flow passage. A first passage wall that divides the passage in the column direction of the cylinder bore is provided, and a second passage wall that forms the second blow-by gas flow passage on the side of the central axis of the cylinder bore is provided below the water jacket and on the cylinder wall. It is characterized by being provided by being polymerized with.

[Action]

According to the configuration of this invention, after casting, the sand of the core flows well in the blow-by gas flow passage, which facilitates sand removal of the core and facilitates confirmation of sand falling from the bottom side. Can be done. Further, since the thin wall is not likely to occur between the cylinder bores, the wall thickness of the cylinder wall can be made uniform and the deformation of the cylinder bore can be prevented. Further, since the passage wall forming the blow-by gas flow passage is arranged below the water jacket, the cylinder wall and the passage wall overlap and form a double layer below the water jacket, and internal noise is leaked to the outside. Can be avoided as much as possible, and the generation of noise to the outside can be reduced.

〔Example〕

Embodiments of the present invention will be described in detail and specifically below with reference to the drawings.

1 to 7 show an embodiment of the present invention.
In the figure, 2 is a cylinder block for multiple cylinders that constitutes an internal combustion engine. A plurality of cylinder bores 4 are formed in series in the cylinder block 2.

In addition, in the cylinder block 2, a water jacket 6 and a blow-by gas flow passage 8 are arranged along each cylinder bore 4.
And are formed.

The water jacket 6 is the deepest portion of the depth D that does not reach the skirt portion (crankcase) 12 from the head mating surface 10 along the cylinder bore 4 and along the cylinder bore 4.
Up to 14 are formed (see FIG. 4).

The blow-by gas flow passage 8 is formed between the cylinder bores 4 and 4 and laterally near the cylinder head bolt boss 16.

As shown in FIGS. 1, 2, and 4, the blow-by gas flow passage 8 has a first blow-by gas flow passage 8-1 (first, second, and third) extending from the head mating surface 10 to the deepest portion 14 of the water jacket 6.
The first passage cross-sectional area S1 (fourth indicated by depth H1) is substantially the same.
The second blow-by gas flow passage below the deepest portion 14 of the water jacket 6
8-2 indicates the first passage cross-sectional area S1 (indicated by the depth H2 in FIGS. 1 and 2)
It is formed with a second passage sectional area S2 (see FIG. 4) larger than the above. Therefore, the second blow-by gas flow passage 8-2
Are formed wider than the first blow-by gas flow passage 8-1 in the column direction of the cylinder bores 4.

At this time, as shown in FIG. 2, the adjacent second blow-by gas flow passages 8-2, 8-2 are divided by the first passage wall 18a. That is, as shown in FIG. 14, the interposition part 12 is provided between the passage walls 120, 120 forming the second blow-by gas flow passages 8-2, 8-2.
Configure so that 2 is not formed.

Further, the core for forming the blow-by gas flow passage 8 is formed of sand containing resin.

FIG. 7 shows the second passage wall 18b forming the second blow-by gas flow passage 8-2 in order to increase the second passage cross-sectional area S2 of the second blow-by gas flow passage 8-2. , Below the water jacket 6 and the cylinder bore 4
When the cylinder wall 20 and the second passage wall 18b are overlapped with each other, the cylinder wall 20 and the second passage wall 18b are overlapped with each other.

 Next, the operation of this embodiment will be described.

During the casting operation of the cylinder block 2, sand containing resin is used for the core for forming the blow-by gas flow passage 8. This core has a first depth H1 from the head mating surface 10 to the deepest portion 14 of the water jacket 6.
It has a predetermined thickness to form the passage cross-sectional area S1 and is formed larger than the above-mentioned thickness to form the second passage cross-sectional area S2 below the deepest portion 14.

As a result, after casting, the sand of the core has good fluidity, and it is possible to easily remove the sand of the core, and as shown in FIG.
That is, it is possible to easily confirm the falling of sand from the crankcase 12 side.

In the blow-by gas flow passage 8, sand containing resin in the core is used, or the second passage cross-sectional area S2 of the second blow-by gas flow passage 8-2 is set to the first blow-by gas flow passage 8
-Because it was made larger than the first passage cross-sectional area S1 of -1,
As shown in FIG. 6, an intermediate portion 4M between the cylinder bores 4 and 4
The draft of the P portion of the location becomes small, it is possible to avoid the occurrence of useless meat, the wall thickness of the cylinder wall 22 can be made uniform, and the cylinder bore 4 is prevented from being deformed due to the heat effect during use. The diameter of the cylinder bore 4 can be guaranteed to be constant.

Further, as shown in FIG. 7, since the second passage wall 18b forming the blow-by gas flow passage 8 is arranged below the deepest portion 14 of the water jacket 6, the second passage wall 18b and the cylinder wall 20 are separated from each other. Polymerization reduces the transmitted sound from the inside and has a large sound insulation effect, which can reduce the generation of noise to the outside, and can also improve the strength of the site.

[Effect of device]

As is apparent from the above detailed description, according to the present invention, the blow-by gas flow passage is formed between the adjacent cylinder bores and laterally in the vicinity of the cylinder head bolt boss,
A first blow-by gas flow passage from the mating surface of the head to the deepest portion of the water jacket and a second blow-by gas flow passage that is in communication with the first blow-by gas flow passage and is below the deepest portion of the water jacket. And a second blow-by gas flow passage is formed in the column direction of the cylinder bore so that the second blow-by gas flow passage has a second cross-sectional area larger than that of the first blow-by gas flow passage. The first blow-by gas flow passage is formed wider than the first blow-by gas flow passage, and the first blow-by gas flow passage is formed laterally with respect to the center axis of the cylinder bore. Since the second passage wall is provided below the water jacket and overlaps with the cylinder wall, the blow-by gas flow passage is provided after casting. The so sand of the core is good liquidity,
The sand can be easily removed from the core, and the sand can be easily confirmed from the bottom side.

Also, since it is less likely to produce a thin wall between adjacent cylinder bores, the wall thickness of the cylinder wall can be made uniform, the cylinder bore is prevented from being deformed due to the heat effect during use, and the diameter of the cylinder bore is kept constant. Can be secured.

Further, since the second passage wall forming the blow-by gas flow passage is arranged below the water jacket, the cylinder wall and the second passage wall overlap and form a double layer below the water jacket, so that the internal noise is reduced to the outside. Leakage can be avoided as much as possible, and the generation of noise to the outside can be reduced.

[Brief description of drawings]

1 to 7 show an embodiment of the present invention, FIG. 1 is a schematic perspective view of a cylinder block, FIG. 2 is a schematic side view of the cylinder block, FIG. 3 is a plan view of the cylinder block, and FIG.
FIG. 6 is a side view of the cylinder block in FIG. 3, FIG. 5 is an explanatory view for confirming the sand falling state, FIG. 6 is an explanatory view of a state in which no extraneous material is generated between the cylinder bores, and FIG. It is explanatory drawing of the state which the passage wall and the superposition | polymerization. 8 to 13 show a conventional cylinder block, FIG. 8 is a plan view of the cylinder block, FIG. 9 is a side view of the cylinder block in FIG. 8, and FIG. 10 is difficult to confirm sand removal or sand removal. Fig. 11 is a half cross-sectional view of the cylinder block, Fig. 12 is an explanatory diagram of the state in which the flesh is generated by the arrow XII-XII in Fig. 11, and Fig. 13 is the internal noise leaked to the outside. It is explanatory drawing of a state. FIG. 14 is an explanatory view of a state in which an interposition part is formed between the passage walls of the second blowby gas flow passage. In the figure, 2 is a cylinder block, 4 is a cylinder bore, 6 is a water jacket, 8 is a blow-by gas flow passage, 10 is a head mating surface, 12 is a skirt portion, 14 is the deepest portion,
18a and 18b are first and second passage walls, and 20 is a cylinder wall.

Claims (1)

(57) [Scope of utility model registration request] 1. A water jacket formed along the cylinder bore to a depth that does not reach the skirt portion from the head mating surface, and a blow-by gas flow passage formed along the water jacket so as to penetrate from the head mating surface into the skirt portion. In the structure of the cylinder block having the above, the blow-by gas flow passage is formed between the adjacent cylinder bores and laterally in the vicinity of the cylinder head bolt boss, and the blow-by gas flow passage is formed from the head mating surface to the water jacket. A first blow-by gas flow passage to the deepest portion and a second blow-by gas passage communicating with the first blow-by gas flow passage and located below the deepest portion of the water jacket.
A second blow-by gas flow passage, and the second blow-by gas flow passage is formed to have a second cross-sectional area of the second blow-by gas flow passage larger than that of the first blow-by gas flow passage. Is formed wider in the column direction of the cylinder bore than the first blow-by gas flow passage, and a first passage wall that partitions the second blow-by gas flow passage in the column direction of the cylinder bore is provided. A structure of a cylinder block, characterized in that a second passage wall forming a passage on the side of the central axis of the cylinder bore is provided below the water jacket and overlapping the cylinder wall.