JPH06330720A - Positive crankcase ventilation of water cooling internal combustion engine - Google Patents

Abstract

PURPOSE:To prevent condensed water from being mixed into separated or recovered oil by effectively discriminating only oil mist without condensing the moisture contained in a blowby gas. CONSTITUTION:A blowby gas G is guided from a crank chamber 6 into a positive crankcase ventilation 1. A first chamber 20 for discriminating part of oil mist contained in a blowby gas G and a second chamber 30 for guiding the blowby gas G from the first chamber 20 and for discriminating the remainder of the oil mist contained in the blowby gas G, are provided. The first chamber 20 is provided on the cylinder head cover of a water cooling internal combustion engine 2, while the second chamber 30 is provided on the cylinder head 12 and in the vicinity of a water jacket 15 in this positive crankcase ventilation of water cooling internal combustion engine.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a blow-by gas recirculation device for recirculating blow-by gas generated in an internal combustion engine.

[0002]

2. Description of the Related Art Generally, in an internal combustion engine of an automobile or the like, there is so-called blow-by gas in which a part of combustion gas in a combustion chamber leaks from between a piston and a cylinder to a crankcase side. This blow-by gas contains harmful hydrocarbons (HC)
It contains a large amount of and cannot be released directly to the atmosphere. Therefore, conventionally, a blow-by gas recirculation device has been proposed that recirculates blow-by gas into a combustion chamber through an intake system. As shown in the conceptual diagram of FIG. 7, the blow-by gas 52 leaking to the crank chamber 51 side is fed to the combustion chamber 55 via the breather hose 53 and the air cleaner 54, and re-combusted there. .

[0003]

By the way, the blow-by gas contains oil mist and water. When this blow-by gas is recirculated, the oil mist adheres to parts of the intake system and fuel system and causes malfunction. Becomes Further, the water content becomes condensed water, which causes the lubricating oil to become cloudy and deteriorate. However, it was difficult to sufficiently remove such a factor with the conventional blow-by gas recirculation device.

Therefore, an object of the present invention is to efficiently separate oil mist without condensing water contained in blow-by gas.

[0005]

To achieve the above object, the present invention introduces blow-by gas from a crank chamber into a blow-by gas recirculation device to separate a part of oil mist contained in the blow-by gas. A first chamber,
A second chamber for introducing blow-by gas from the first chamber to separate the rest of the oil mist contained in the blow-by gas is provided, and the first chamber is provided for the cylinder head cover of the water-cooled internal combustion engine, and A second chamber is provided at the cylinder head and near the water jacket. Further, the second chamber is integrally formed with a water temperature valve attached to the outlet of the cooling water passage of the cylinder head.

[0006]

The first chamber introduces blow-by gas from the crank chamber to separate a part of the oil mist contained in the blow-by gas. The second chamber introduces blow-by gas from the first chamber and separates the rest of the oil mist contained in this blow-by gas. Further, the inside of the first chamber is at a high temperature due to heat conduction from the cylinder head cover, and the inside of the second chamber is also at a high temperature due to heat conduction between the cooling water heated by the water jacket and the cylinder head. Therefore, the first chamber and the second chamber do not condense the water contained in the blow-by gas, and prevent the condensed water from being mixed into the separated / collected oil.

[0007]

Embodiments of the present invention will be described below with reference to the accompanying drawings. The drawings should be viewed in the direction of the reference numerals.
FIG. 1 is a conceptual diagram of an embodiment of a blow-by gas recirculation system for a water-cooled internal combustion engine according to the present invention. The blow-by gas recirculation device 1 has a blow-by gas G leaked from a combustion chamber 3 of a water-cooled internal combustion engine 2 into a crank chamber 6 through a gap between a piston 4 and a cylinder 5, and has an air cleaner 7 and an intake manifold 8. It is a system that recirculates to the system 9 and reburns it.

The water-cooled internal combustion engine 2 has a first chamber 2 which also serves as a cylinder block 11 having a water jacket, a cylinder head 12, and a cylinder head cover.
It is configured by combining 0s. Below the cylinder block 11, an oil pan 14 that stores lubricating oil is attached. The blow-by gas recirculation apparatus 1 introduces the blow-by gas G from the crank chamber 6 to generate the blow-by gas G.
A first chamber (cylinder head cover) 20 for separating a part of the oil mist contained in, and a blow-by gas G is introduced from the first chamber 20 to separate the rest of the oil mist contained in the blow-by gas G. And a second chamber 30. The oil mist separated in the first chamber 20 and the second chamber 30 is the oil pan 1
Recovered in 4.

The second chamber 30 includes the cylinder head 12
In addition, in the vicinity of the water jacket 15, it is formed integrally with a water temperature valve 17 attached to the outlet of the cooling water passage 16. The cooling water passage 16 includes a radiator 18
Further, the water pump 19 is connected to the cooling water inlet of each water jacket (not shown) of the water-cooled internal combustion engine 2.

FIG. 2 is a side view of the water-cooled internal combustion engine according to the present invention. The upper part of the cylinder head 12 is covered with the first chamber 20, and the second chamber 30 is attached to the left side surface in FIG.

FIG. 3 is a plan view of a water-cooled internal combustion engine according to the present invention. The gas outlet pipe 21 of the first chamber 20 is
The gas inlet pipe 31 of the chamber 30 is connected by a connection hose 40.

FIG. 4 is an enlarged sectional view of the principal part taken along line 4-4 of FIG. The first chamber 20 has a main body 22 that is open at the bottom and is formed in a substantially arm shape.
By closing the lower surface facing 2 with a closing plate 23, a chamber internal space 24 is formed inside. The closing plate 23 is provided with a gas inlet hole 23a that communicates the crank chamber 6 (see FIG. 1) with the chamber inner space 24. The gas inlet hole 23a has a blow-by gas G on the crank chamber 6 side.
A reed valve 25 that is opened and closed by the gas pressure of is provided.

A gas outlet pipe 21 is provided in the chamber space 24.
An inner end 21a of the main body 22 is projected, and an inner baffle 22a and an outer baffle 22b are doubly hung from the upper wall of the main body 22 around the inner end 21a. Inner baffle 22
The lower part of the inner passage 26 surrounded by a is the closing plate 2
It is closed by an auxiliary baffle 27 on the 3rd side. Outer passage 2 surrounded by inner baffle 22a and outer baffle 22b
8 communicates between the chamber inner space 24 and the inner passage 26.

FIG. 5 is an enlarged side view of an essential part of a cross section taken along line 5-5 of FIG. The second chamber 30 includes a water jacket 15 of the cylinder head 12, a cooling water passage 16 of the water jacket 15, a water temperature valve 17 attached to an outlet of the cooling water passage 16, and a water jacket 1.
5 is integrally formed with a chamber inner space 32 provided in the vicinity of 5, and is bolted to the side surface of the cylinder head 12.

The chamber inner space 32 is divided by a baffle 33 and communicates with each other. A lower passage 34 and an upper passage 3
5, and an oil sump 36 is provided below the lower passage 34. A gas inlet pipe 31 is attached to the lower passage 34 with its inner end protruding, and a gas outlet pipe 37 is attached to the upper passage 35 with its inner end protruding. The gas outlet pipe 37 is connected to the intake system 9 (see FIG. 1), and the chamber inner space 32 has an oil discharge portion 38 that receives the oil overflowed from the oil sump 36 and returns it to the oil pan 14 (see FIG. 1). It is formed integrally.

FIG. 6 is an external view of the second chamber according to the present invention. The water temperature valve 17 opens and closes the passage in accordance with the water temperature in the cooling water passage 16. For example, a temperature sensitive valve body portion 17a that is opened and closed by the expansion and contraction action of the wax enclosed in the temperature sensitive portion, It is configured to be mounted between the case portion 17b and the lid body portion 17c. The case portion 17b is formed integrally with the cooling water passage 16, and the lid portion 17c is detachably attached thereto. The lid portion 17c includes a radiator 18
A cooling water outlet pipe 17d directed to (see FIG. 1) is integrally formed.

The operation of the blow-by gas recirculation system for a water-cooled internal combustion engine having the above construction will be described below. As shown in FIG. 1, the blow-by gas G leaking from the combustion chamber 3 to the crank chamber 6 through the gap between the piston 4 and the cylinder 5 is
The gas enters into the chamber inner space 24 of the first chamber 20 through the gas inlet hole 23a. This blow-by gas G collides with the baffles 22a, 22b, 27 and the like and falls by gravity while passing through the outer passage 28 and the inner passage 26 from the chamber inner space 24, so that a part of the contained oil mist is lost. It is separated and passes through the gas inlet pipe 31 from the gas outlet pipe 21 via the connecting hose 40 and enters the second chamber 30.

While the blow-by gas G passes through the lower passage 34 and the upper passage 35 of the second chamber 30, the remaining portion of the contained oil mist is separated by collision with the baffle 33 or the like and gravity drop. The gas returns from the gas outlet pipe 37 to the intake system 9 and is re-combusted in the combustion chamber 3. The oil mist separated from the blow-by gas G in the first chamber 20 and the second chamber 30 is collected in the oil pan 14.

Next, the operation of the second chamber 30 will be described. As shown in FIG. 5, the oil mist contained in the blow-by gas G is separated in the lower passage 34 and the upper passage 35, and is temporarily stored in the oil sump 36 as separated oil. This separated oil overflows from the oil sump 36 and passes through the oil discharge part 38 to the oil pan 14 (see FIG. 1).
And used as lubricating oil in the crank chamber 6.

By the way, as shown in FIG. 1, the chamber internal space 24 of the first chamber 20 is in a high temperature state due to the combustion heat of the combustion chamber 3. Further, the chamber inner space 32 of the second chamber 30 is in a high temperature state due to heat conduction between the cylinder head 12 heated by the combustion heat of the combustion chamber 3 and the cooling water heated by the water jacket 15. The chamber internal space 24 and the chamber internal space 32 are
They are arranged at positions close to each other, communicate with each other by a connection hose 40, and are kept at a relatively high temperature. Therefore, in the blow-by gas G passing through the chamber internal spaces 24 and 32, the contained water is not condensed. Therefore, the water contained in the blow-by gas G does not mix with the separated oil separated in the chamber internal spaces 24, 32.

In the above embodiment, the first chamber 2
The number 0 is not limited to the configuration that also serves as the cylinder head cover, and may be any configuration provided on the cylinder head cover of the water-cooled internal combustion engine 2.

[0022]

As described above, according to the present invention, the blow-by gas recirculation apparatus is provided with the blow-by gas from the crank chamber to separate a part of the oil mist contained in the blow-by gas, and the first chamber, A second chamber for introducing blow-by gas from the first chamber to separate the rest of the oil mist contained in the blow-by gas is provided, and the first chamber is provided for the cylinder head cover of the water-cooled internal combustion engine, and Since the second chamber is provided in the cylinder head and in the vicinity of the water jacket, the first chamber and the second chamber are warmed, and the blowby gas is warmed in the second chamber so that the moisture contained in the blowby gas is not condensed. Moreover, it is possible to efficiently separate only the oil mist.

Further, since the second chamber is formed integrally with the water temperature valve attached to the outlet of the cooling water passage of the cylinder head, the two chambers are integrated and miniaturized, and the number of parts is reduced. At the same time, mounting on the cylinder head becomes easy.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of an embodiment of a blow-by gas recirculation system for a water-cooled internal combustion engine according to the present invention.

FIG. 2 is a side view of a water-cooled internal combustion engine according to the present invention.

FIG. 3 is a plan view of a water-cooled internal combustion engine according to the present invention.

FIG. 4 is an enlarged cross-sectional view of the main part of line 4-4 in FIG.

5 is an enlarged side view of an essential part of a cross section taken along line 5-5 of FIG.

FIG. 6 is an external view of a second chamber according to the present invention.

FIG. 7 is a conceptual diagram of a conventional blow-by gas recirculation system for an internal combustion engine.

[Explanation of symbols]

1 ... Blow-by gas recirculation device, 2 ... Water-cooled internal combustion engine, 3
... combustion chamber, 4 ... piston, 5 ... cylinder, 6 ... crank chamber, 9 ... intake system, 12 ... cylinder head, 15 ... water jacket, 16 ... cooling water passage, 17 water temperature valve, 2
0 ... 1st chamber (cylinder head cover), 30 ... 2nd chamber, 40 ... Connection hose.

Claims (2)

[Claims] 1. A blow-by gas recirculation device for recirculating a blow-by gas leaking into a crank chamber through a gap between a piston and a cylinder in a water-cooled internal combustion engine to an intake system for re-combustion. Is a first chamber for introducing blow-by gas from the crank chamber to separate a part of the oil mist contained in the blow-by gas, and a blow-by gas introduced from the first chamber for being contained in the blow-by gas. A second chamber for separating the rest of the oil mist, the first chamber being provided in the cylinder head cover of the internal combustion engine, and the second chamber being provided in the cylinder head and in the vicinity of the water jacket. A blow-by gas recirculation device for a water-cooled internal combustion engine. 2. The blow-by of a water-cooled internal combustion engine according to claim 1, wherein the second chamber is formed integrally with a water temperature valve attached to an outlet of a cooling water passage of the cylinder head. Gas recirculation device.