JP3025861B2 - Engine breather device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a breather device for an engine, and more particularly to a device capable of preliminarily separating oil mist before blow-by gas reaches an oil separation valve.

[0002]

2. Description of the Related Art FIG. 3 shows a prior art of a breather device for an engine. This has the following basic structure as in the present invention.

That is, the breather chamber 101 is divided into an inlet chamber 103 and an outlet chamber 104 by a valve holder plate 102, and a gas introduction space 106 facing the blow-by gas inlet 105 is provided in the inlet chamber 103. 1
06 is communicated with a crankcase 107 through a blow-by gas inlet 105, a valve hole 108 is made in the valve holder plate 102, an oil separating valve 109 is attached to the valve holder plate 102 on the outlet chamber 104 side, and an inlet chamber 103 side is provided. The valve hole cover 110 is attached to the valve holder plate 102, the valve hole 108 faces the space 111 inside the rectangular parallelepiped cover, and the valve hole facing wall 112, the long side wall 113, and the short side wall 114 of the valve hole cover 110 are used. A long side opening 115 and a short side opening 116 are provided so as to surround the in-cover space 111 and to oppose the long side wall 113 and the short side wall 114, respectively.

In this prior art, a valve hole cover 110 is provided.
The valve hole-facing wall 112 faces the gas introduction space 106, and the blow-by gas introduced into the gas introduction space 106 is divided into two directions. As shown in FIG. As shown in FIG. 1B, the second branch 133 flows from the long side opening 115 into the cover internal space 111 from the short side opening 116 without oil separation.

[0005]

In the above prior art, if the oil mist content of the blow-by gas introduced into the gas introduction space 106 is high, a large amount of separation oil adheres around the valve hole 108, and this separation oil As a result, the oil separating valve 109 comes into close contact with the periphery of the valve hole 108 and causes malfunction, and when the internal pressure of the crankcase rises to a certain degree, the oil separating valve 109 opens suddenly, and the valve hole Separated oil adhering around 108 may blow out from outlet chamber 104 at once.

For this reason, in the closed breather in which the outlet chamber 104 is communicated with the intake passage, unburned harmful components in the exhaust gas increase due to the oil flowing into the combustion chamber, which may adversely affect the surrounding environment. . Also, the exit room 10
In the open breather that releases 4 into the atmosphere, the oil leaked into the atmosphere may adversely affect the surrounding environment. In addition, any type of breather consumes a large amount of oil.

It is an object of the present invention to provide a breather device for an engine that can preliminarily separate oil mist before blow-by gas reaches an oil separation valve.

[0008]

According to the present invention, as shown in FIG. 1, a breather chamber 1 is divided into an inlet chamber 3 and an outlet chamber 4 by a valve holder plate 2, and a blow-by gas inlet 5 is provided in the inlet chamber 3. The gas introduction space 6 is provided so as to communicate with the crankcase 7 through the blow-by gas inlet 5, a valve hole 8 is made in the valve holder plate 2, and the valve holder plate is provided on the outlet chamber 4 side. 2, an oil separating valve 9 is attached, a valve hole cover 10 is attached to the valve holder plate 2 on the inlet chamber 3 side, and a valve hole 8 is made to face a rectangular parallelepiped cover inner space 11, and the valve hole cover 10 is opened.
The interior wall 11 of the cover is surrounded by the valve hole facing wall 12, the long side wall 13, and the short side wall 14, and the long side opening 15 of the cover inside space 11 is opposed to the long side wall 13 and the short side wall 14, respectively. And a short-side opening 16 provided in the breather device of the engine, characterized in that it is as follows.

That is, the valve hole cover 10 is covered with a gutter-shaped throttle forming case 17 and the throttle forming case 17 is formed.
The gas bypass space 19 is formed between the bottom plate 18 of the throttle forming case 17 and the valve hole facing wall 12 of the valve hole cover 10 so as to face the gas introduction space 6. A gas inversion space 22 is formed in the inlet chamber 3 on the side of the short side wall 14 of the valve hole cover 10, and the gas introduction space 6 communicates with the gas bypass passage 19 in the gas inversion space 22. Is led out so as to be closer to the inlet chamber wall 25 than the short side opening edge 24 of the valve hole cover 10, and a gas reversal path 27 is formed in the lead-out opening edge 23. 27 is a gas detour 19
And the inside space 11 of the cover.

A reverse roadside throttle gap 29 is provided between the outlet opening edge 23 of the throttle forming case 17 and the inlet chamber wall 25.
Is formed, and the gas reversing path 27 is formed by the reversing path side throttle gap 29.
And the gas introduction space 6 are communicated with each other to form a throttle forming case 17.
The long edge opening 15 is covered with the folded edge 30 of the cover, and a space-in-cover-side throttle gap 31 is formed between the folded edge 30 and the valve holder plate 2. The inner space 11 and the gas introduction space 6 are communicated with each other.

[0011]

According to the present invention, as shown in FIG. 1, blow-by gas is introduced into the gas introduction space 6, and is divided into three directions.
As shown in FIG. 1 (B), the first branch flow 32 passes through the gas inversion space 22, the gas bypass passage 19, and the gas inversion passage 27 in order, and flows into the in-cover space 11, but along the long side direction. During the passage through the long gas bypass passage 19, most of the oil mist contained in the first branch flow 32 adheres and condenses on the inner surface of the passage. The second branch 33 flows into the cover internal space 11 from the inversion path side throttle gap 29 through the gas inversion path 27, and due to the throttle resistance of the inversion path side throttle gap 29, the oil contained in the second branch 33 is removed. Most of the mist is separated. As shown in FIG. 1A, the third branch flow 34 flows into the cover internal space 11 from the cover internal space-side throttle gap 31. Most of the oil mist contained in the split stream 34 is separated.

As described above, before reaching the oil separation valve 9 due to the adhesion and condensation of oil mist on the inner surface of the gas bypass passage 19 and the throttle resistance of the reverse path side throttle gap 29 and the space throttle side gap 31 in the cover. The oil mist is preliminarily separated from the blow-by gas.

[0013]

According to the present invention, even if the oil mist content of the blow-by gas introduced into the gas introduction space 6 increases, the oil mist is preliminarily separated before reaching the oil separation valve 9. The malfunction of the oil separating valve 9 is unlikely to occur, and the abrupt opening of the oil separating valve 9 based on the pressure increase of the crankcase suppresses the deficiency of the separated oil flowing out of the outlet chamber 4. For this reason,
In the closed breather in which the outlet chamber 4 is communicated with the intake path, unburned harmful components in the exhaust gas increase due to the oil flowing into the combustion chamber, and defects that adversely affect the surrounding environment can be suppressed. Further, in the open breather in which the outlet chamber 4 is opened to the atmosphere, it is possible to suppress defects that adversely affect the surrounding environment due to the oil flowing out to the atmosphere. In addition, the oil consumption is reduced in each case.

[0014]

An embodiment of the present invention will be described with reference to the drawings.
1 and 2 are views for explaining an embodiment of the present invention. In this embodiment, a vertical overhead valve gasoline engine is used.
The structure of this engine is as follows. That is, FIG.
As shown in (A), the crankcase 7 and the cylinder 35
A cylinder head 37 is mounted on an upper portion of a cylinder block 36 integrally formed with the above, and a fuel tank 38 is supported above the cylinder head 37. An air cleaner 40 is attached to the cylinder head 37 via a carburetor 39. A rocker arm 41 is disposed above the cylinder head 37, and the rocker arm 41 is
Covered with 2. The rocker arm 41 is driven from a valve cam shaft 43 via a tappet 44 and a push rod 45 in this order.

The valve operating cam shaft 43 is disposed in the crankcase 7, the tappet 44 is fitted in the guide boss 46, and the push rod 45 is accommodated in the push rod chamber 47.
The push rod chamber 47 is formed in a series over the cylinder head 37 and the cylinder 35, and the guide boss 46 extends from a bottom wall 48 of the push rod chamber 47.

The structure of the lubricating device for this engine is as follows. That is, the engine oil 49 is stored in the inner bottom of the crankcase 7 and the oil depper 51 of the connecting rod 50 is stored.
It is made to scrape up. Above the scraping side of the engine oil 49, a passage inlet 53 of a blow-by gas floating passage 52 is opened. Blow-by gas floating passage 52
Are formed in series over the cylinder 35 and the cylinder head 37, and the passage outlet 54 thereof faces the intake / exhaust valve 55 and the rocker arm 41. As shown in FIG. 1 (B), a long hole-shaped oil drop hole 56 is formed in the bottom wall 48 of the push rod chamber 47.

According to this lubricating device, the oil depper 51
The engine oil 49 raked up by the above becomes an oil mist, which is contained in the blow-by gas and floats in the blow-by gas floating passage 52, fills the inside of the head cover 42, and lubricates the rocker arm 41 and the like. The oil mist filled in the head cover 42
Adheres and condenses on the inner surface and the like, and returns into the crankcase 7 from the oil drop hole 56 through the push rod chamber 47.

The outline of the structure of the breather device of this engine is as follows. That is, the breather chamber 1 is disposed on the side opposite to the passage outlet 54 of the blow-by gas floating passage 52 with the rocker arm 41 interposed therebetween. The breather chamber 1 is formed over the cylinder head 37 and the head cover 42, and has a blow-by gas inlet 5 and an oil return port 57.
, An oil separation valve 9 is provided inside, and connected to an air cleaner 40.

According to the breather device, when the internal pressure of the crankcase 7 rises, the blow-by gas flows into the breather chamber 1 from the blow-by gas inlet 5 and the oil mist contained in the blow-by gas is removed by the oil separating valve 9. Then, the blow-by gas separated from the oil is sucked by the air cleaner 40, thereby suppressing an increase in the internal pressure of the crankcase 7. The blow-by gas sucked by the air cleaner 40 is reburned in the combustion chamber, and the separated oil is returned into the crankcase 7 from the oil return port 57.

The details of the structure of this breather device are as follows. That is, as shown in FIG. 1, the breather chamber 1 is divided into an inlet chamber 3 and an outlet chamber 4 by a valve holder plate 2, and a gas introduction space 6 facing the blow-by gas inlet 5 is provided in the inlet chamber 3. is there. The valve holder plate 2
It is fixed by being sandwiched between the head cover 42 and the cylinder head 37. The blow-by gas inlet 5 is connected to the inlet chamber 3
It is located at an intermediate height. The oil return port 57
Opened toward the push rod chamber 47 at the inner bottom of the inlet chamber 3.

As shown in FIG. 2, the gas introduction space 6 communicates with the crankcase 7 through the blow-by gas inlet 5. As shown in FIG. 1, a valve hole 8 is formed in the valve holder plate 2 and an oil separation valve 9 is attached to the valve holder plate 2 on the outlet chamber 4 side. The oil separating valve 9 is formed of an elastic metal plate.
Oil separation is performed by the throttle resistance caused by the blow-by gas pushing up the oil separation valve 9. The maximum valve opening position of the oil separating valve 9 is regulated by the stopper piece 58. The stopper piece 58, the oil separation valve 9 and the valve hole cover 10 are attached to the valve holder plate 2 with rivets 59.

A valve hole cover 10 is attached to the valve holder plate 2 on the inlet chamber 3 side, and the valve hole 8 faces a space 11 inside the rectangular parallelepiped cover. A wall 13 and a short side wall 14 surround the interior space 11 of the cover, and a long side opening 15 and a short side opening 16 of the interior space 11 of the cover are provided at positions facing the long side wall 13 and the short side wall 14, respectively. is there.

In this embodiment, the following configuration is employed to preliminarily separate the oil mist before the blow-by gas reaches the oil separating valve 9. That is, the valve hole cover 10 is covered with a gutter-shaped case 17 for forming a diaphragm,
The bottom plate 18 of the aperture forming case 17 is connected to the gas introduction space 6.
A gas detour passage 19 is formed between the bottom plate 18 of the throttle forming case 17 and the valve hole facing wall 12 of the valve hole cover 10 along the long side direction, and the short side of the valve hole cover 10 is formed. A gas reversal space 22 is provided in the entrance chamber 3 on the wall 14 side.
The gas inversion space 22 allows the gas introduction space 6 to communicate with the gas bypass passage 19, and the opening edge 23 of the throttle forming case 17 is connected to the short side opening edge 24 of the valve hole cover 10.
The gas reversing path 27 is formed in the outlet opening edge portion 23, and the gas reversing path 19 communicates with the cover internal space 11 in the gas reversing path 27. .

The reverse roadside throttle gap 29 is located between the outlet opening edge 23 of the throttle forming case 17 and the inlet chamber wall 25.
Is formed, and the gas reversing path 27 is formed by the reversing path side throttle gap 29.
And the gas introduction space 6 are communicated with each other to form a throttle forming case 17.
The folded edge 30 covers the long side opening 15, and a space 31 in the cover is formed between the folded edge 30 and the valve holder plate 2. 11 and the gas introduction space 6 are communicated.

[Brief description of the drawings]

1A and 1B are diagrams illustrating a main part of a breather device for an engine according to an embodiment, wherein FIG. 1A is a vertical sectional front view, FIG. 1B is a cross-sectional view taken along line BB of FIG. 1A, FIG. 1C is an exploded perspective view of parts around the oil separation valve.

FIG. 2 is a diagram for explaining an engine according to the embodiment.
(A) is a vertical sectional front view, and FIG. 2 (B) is BB in FIG. 2 (A).
It is a line sectional view.

3A and 3B are diagrams illustrating a main part of a breather device for an engine according to a conventional technique, wherein FIG. 3A is a diagram corresponding to FIG.
3B is a diagram corresponding to FIG. 1B, and FIG. 3C is a diagram corresponding to FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Breather chamber, 2 ... Valve holder plate, 3 ... Inlet chamber, 4 ... Outlet chamber, 5 ... Blow-by gas inlet, 6 ... Gas introduction space, 7 ... Crankcase, 8 ... Valve hole, 9 ... Oil separation valve, 10 ... Valve hole cover, 11 ... Space in cover, 12 ... Valve hole facing wall, 13 ... Long side wall, 14 ...
Short side wall, 15: long side opening, 16: short side opening, 17: diaphragm forming case, 18: bottom plate, 19: gas bypass passage, 22
... gas reversal space, 23 ... opening edge, 24 ... short side opening edge, 25 ... inlet chamber wall, 27 ... gas reversal path, 29 ... reversal path side throttle gap, 30 ... folded edge, 31 ... cover inner space side Aperture gap.

Claims (1)

(57) [Claims] The breather chamber (1) is connected to a valve holder plate.
In (2), it is divided into an entrance room (3) and an exit room (4), and the entrance room (3)
Gas introduction space with blow-by gas inlet (5) facing inside
(6), the gas introduction space (6) is communicated with the crankcase (7) through the blow-by gas inlet (5), a valve hole (8) is opened in the valve holder plate (2), and the outlet chamber ( 4)
Oil separation valve on the valve holder plate (2) on the side
(9) is attached, and a valve holder plate is installed on the inlet chamber (3) side.
The valve hole cover (10) is attached to (2), and the valve hole (8) faces the space (11) inside the rectangular parallelepiped cover.
(10) Valve hole facing wall (12), long side wall (13) and short side wall
(14) surrounds the inside space (11) of the cover, and the opening (15) of the long side (15) and the short side of the space (11) in the cover at a position facing the long side wall (13) and the short side wall (14), respectively. Opening (16)
A breather device for an engine, comprising: a valve hole cover (10) having a gutter-shaped throttle forming case (17);
The bottom plate (18) of the case (17) faces the gas introduction space (6), and the bottom plate (18) of the case (17) faces the valve hole of the valve hole cover (10). Wall (1
2), the gas bypass passage (1) along the long side direction.
9), a gas inversion space (22) is formed in the inlet chamber (3) on the short side wall (14) side of the valve hole cover (10), and the gas inversion space (22) is formed in the gas inversion space (22). 6) and gas bypass
(19), and the opening edge (23) of the aperture forming case (17) is connected to the short side opening edge (24) of the valve hole cover (10).
Out to the inlet chamber wall (25), a gas reversing path (27) is formed in the outlet opening edge (23), and the gas reversing path (27) is connected to the gas bypass path (19). Cover space
(11) to form a reverse roadside throttle gap (29) between the outlet opening edge (23) of the throttle forming case (17) and the inlet chamber wall (25). In (29), the gas reversing path (27) is communicated with the gas introduction space (6), and the long side opening (15) is covered with the folded edge portion (30) of the aperture forming case (17). (30) and the valve holder plate (2), a space (31) in the cover space side is formed, and the space (11) in the cover and the gas introduction space are defined by the space space (31) in the cover space.
6. A breather device for an engine, wherein the breather device communicates with (6).