JPH0648092Y2 - Internal combustion engine blow-by passage - Google Patents

Description

The present invention relates to a blow-by passage for an internal combustion engine, and more particularly to a blow-by passage for an internal combustion engine that prevents spattered oil from mixing with blow-by gas.

[Conventional technology]

In the internal combustion engine, blow-by gas leaking from the combustion chamber through the gap between the piston and the cylinder wall into the crankcase is generated. Since this component contains HC of unburned gas, it is necessary to guide it to the combustion chamber again to reburn it. For this purpose, a blow-by passage is provided in the internal combustion engine.

As shown in FIG. 5, the blow-by passage of the internal combustion engine penetrates the cylinder block 104 and the cylinder head 128 to communicate the inside of the crankcase 116 and the inside of the cylinder head cover 130, and the inside of the cylinder head cover 130 and the air cleaner 132. The blow-by gas mixed with the oil 126 in the crankcase 116 is taken from the lower end opening and separated into the blow-by gas and the oil 126 on the cylinder head 128 side, and the blow-by gas is supplied to the air cleaner 132. The oil 126 was returned and sent back into the crankcase 116.

Further, as another blow-by gas passage of an internal combustion engine, as disclosed in Japanese Utility Model Laid-Open No. 59-79511, a blow-by gas passage is formed through one side of a predetermined crank bearing portion of a cylinder block, and In some cases, a cover was attached to the opening facing the inside of the crankcase of the passage to prevent the intrusion of lubricating oil.

[Problems to be solved by the invention]

By the way, in the blow-by passage of the conventional internal combustion engine, the lower end opening on the crankcase side is provided above the crankshaft or in the tangential direction of the rotation circle of the crankshaft.

As a result, the atomized oil scraped up by the rotation of the crankshaft is mixed with the blow-by gas in the vicinity of the lower end opening of the blow-by passage, which increases the oil consumption and is economically disadvantageous. There is.

[Purpose of device]

Therefore, in order to eliminate the above-mentioned inconvenience, the object of the present invention is to provide a crankshaft held by a cylinder block and a crank bearing cap, and to provide a mating surface on either the lower surface of the cylinder block or the upper surface of the crank bearing cap. Has a groove parallel to the mating surface that communicates with the lower end opening of the blow-by passage, which reduces oil mixing in the blow-by gas and reduces oil consumption, which is economically advantageous. In addition, it is possible to realize a blow-by passage for an internal combustion engine that is practically advantageous because it is possible to reduce the weight of the cylinder block and reduce the manufacturing cost.

[Means for solving problems]

In order to achieve this object, the present invention relates to a blow-by of an internal combustion engine which communicates the crankcase and the cylinder head cover with each other and communicates the cylinder head cover with the intake system upstream side to reduce blow-by gas to the intake system upstream side. In the passage, the crankshaft is provided so as to be held by a cylinder block and a crank bearing cap, and the lower surface opening of the blow-by passage is connected to one of the mating surfaces of the lower surface of the cylinder block and the upper surface of the crank bearing cap. It is characterized in that a groove portion parallel to the mating surface is provided.

[Action]

With the above configuration, when the internal combustion engine is driven, the blow-by gas mixed with the oil in the crankcase enters the blow-by passage from the groove and is separated into the blow-by gas and the oil. Is returned to the side and the oil is lowered into the crankcase.

At this time, a groove parallel to the mating surface that communicates with the lower end opening of the blow-by passage is provided on either mating surface of the lower surface of the cylinder block and the upper surface of the crank bearing cap. It surely reduces the oil mixture and reduces the oil consumption.

〔Example〕

An embodiment of the present invention will be described in detail below with reference to the drawings.

1 and 2 show an embodiment of the present invention. In FIGS. 1 and 2, 2 is an internal combustion engine and 4 is a cylinder block. A cylinder block 4 of the internal combustion engine 2 has a cylinder (not shown) formed therein, and a piston 6 that moves up and down in the cylinder is fitted therein. The piston 6 is attached to one end side of the connecting rod 8, and the crankshaft is attached to the other end side of the connecting rod 8.
10 is installed.

The crankshaft 10 is rotatably attached to the lower portion of the cylinder block 4 by a crank bearing cap 12.

The cylinder block 4 has a cylinder head (not shown) fixedly mounted on the upper portion thereof and an oil pan 14 on the lower portion thereof.
Is fixedly installed, and the cylinder block 4 and the oil pan 14 form a crankcase 16.

Also, a cylinder head and a cylinder block 4 not shown
A blow-by passage 18 that connects the crankcase 16 to the inside of a cylinder head cover (not shown) is provided in the cylinder, and the blow-by passage 18 communicates with the air cleaner (not shown) from the inside of the cylinder head cover.

Further, the lower surface 4b of the cylinder block 4 and the upper surface 12a of the crank bearing cap 12 are mated with each other, for example, the upper surface 12a of the crank bearing cap 12 has a lower end opening of the blow-by passage 18. A groove portion 22 communicating with 20 and parallel to the mating surface is provided.

That is, the lower end opening 20 of the blow-by passage 18 is provided so as to open on the lower surface of the cylinder block 4, and the lower end opening 20 is provided.
The crank bearing cap 12 corresponding to 20 is provided with a groove 22 communicating with the lower end opening 20. The groove 22 communicates the crankcase 16 and the blow-by passage 18,
Blow-by gas is introduced into the blow-by passage 18.

Reference numeral 24 is a fixing bolt for fixing the crank bearing cap 12 to the cylinder block 4, and 26 is oil accumulated at the bottom of the crankcase 16.

Next, the operation will be described.

When the internal combustion engine 2 is driven, the blow-by gas mixed with the oil 26 in the crankcase 16 enters the blow-by passage 18 through the groove 22 and is separated into the blow-by gas and the oil.

The blow-by gas ascends in the blow-by passage 18 and is returned to the air cleaner side (not shown) through the inside of the cylinder head cover (not shown), and the oil descends through the blow-by passage 18 and is fed into the crankcase 16.

At this time, the lower end opening 20 of the blow-by passage 18 is provided so as to open to the lower surface 4b of the cylinder block 4, and the lower end opening 20 is provided.
Since the crank bearing cap 12 that hits 20 is provided with the groove portion 22 that communicates with the lower end opening portion 20, it is possible to reliably reduce the mixing of a large amount of the oil 26 into the blow-by gas and reduce the consumption amount of the oil 6. There is.

As a result, the mixing of the oil 26 into the blow-by gas can be reduced, the consumption amount of the oil 26 can be reduced, which is economically advantageous, and the internal combustion engine 2 can be reliably lubricated. The performance of the engine 2 can be fully exhibited.

Further, since the lower end opening 20 of the blow-by passage 18 is opened to the lower surface 4b of the cylinder block 4, and the crank bearing cap 12 that hits the lower end opening 20 is provided with the groove 22 that communicates with the lower end opening 20. The cylinder block 4 can be reduced in weight and the manufacturing cost of the cylinder block 4 can be reduced, which is practically advantageous.

The invention is not limited to the above-described embodiment, but various application modifications can be made.

For example, in an embodiment of the invention, a blow-by passage
A lower end opening 20 of the cylinder block 4 is provided on the lower surface 4b of the cylinder block 4, and a groove for connecting the lower end opening 20 to the crank bearing cap 12 which communicates with the lower end opening 20.
22 is provided, but as shown in FIG. 3, a wall portion 34 having a U-shaped cross section is integrally formed at the opening portion of the groove portion 32 so as to open upward so as to prevent mixing of scattered oil into the blow-by gas. It can also be provided and used. This makes it possible to omit the wall portion that has been retrofitted in the related art, reduce the number of parts, and reduce the manufacturing cost. As shown in FIG. 4, a groove portion 42 is provided on the lower surface 4b of the cylinder block 4, and the groove portion 42 and the blow-by passage 18 are provided so as to communicate with each other, so that the scattered oil is prevented from being mixed into the blow-by gas at the opening portion of the groove portion 42. It is also possible to integrally provide the plate-shaped wall portion 44.

[Effect of device]

As described in detail above, according to the present invention, the crankshaft is provided by being held by the cylinder block and the crank bearing cap, and the blowby bypass is provided on one of the mating surfaces of the lower surface of the cylinder block and the upper surface of the crank bearing cap. Since the groove parallel to the mating surface is provided so as to communicate with the opening at the lower end of the passage, it is possible to reduce the mixing of oil into the blow-by gas and to reliably reduce the oil consumption, which is economically advantageous. Further, since the blow-by passage is provided up to the crank bearing cap mating surface portion of the cylinder block, the weight of the cylinder block can be reduced and the manufacturing cost of the cylinder block can be reduced, which is practically advantageous.

[Brief description of drawings]

1 and 2 show an embodiment of the present invention, FIG. 1 is a schematic sectional view of an internal combustion engine, and FIG. 2 is an enlarged perspective view of a main part of a blow-by passage of the internal combustion engine. 3 and 4 are enlarged perspective views of a main part of a blow-by passage of an internal combustion engine showing another embodiment of the present invention. FIG. 5 is a schematic sectional view of a blow-by passage of a conventional internal combustion engine. In the figure, 2 is an internal combustion engine, 4 is a cylinder block, and 6
Is a piston, 8 is a connecting rod, 10 is a crankshaft, 12 is a crank bearing cap, 14 is an oil pan, 16 is a crankcase, 18 is a blow-by passage, 20 is a lower end opening, 22 is a groove, and 24 is a bolt. , 26 is oil.

Claims (1)

[Scope of utility model registration request] Claim: What is claimed is: 1. A crankshaft is provided in a blow-by passage of an internal combustion engine for communicating a crank case and an inside of a cylinder head cover with each other, and communicating the inside of the cylinder head cover with an intake system upstream side to reduce blow-by gas to an intake system upstream side. It is provided so as to be held by a cylinder block and a crank bearing cap, and a mating surface of either the lower surface of the cylinder block or the upper surface of the crank bearing cap is parallel to the mating surface communicating with the lower end opening of the blow-by passage. A blow-by passage for an internal combustion engine, which is provided with a groove.