JP3124908B2 - Oil trapper for internal combustion engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil trapper for an internal combustion engine, and more particularly to a cyclone type oil trapper for use in a blow-by gas reducing device for separating oil mist in blow-by gas.

[0002]

2. Description of the Related Art In a crankcase of an internal combustion engine, there is blow-by gas leaking from a combustion chamber, and the blow-by gas is returned to an intake system to cause deterioration of engine oil due to the gas component. A blow-by gas reducing device for burning is used. This device includes, for example, a shield system that connects a crankcase and an air cleaner with a hose, and a PCV (Positive Crankcase Vendor).
Tilting (ie, forced ventilation of the crankcase) is roughly divided into a PCV system in which the crankcase and the intake system are connected via a valve, and the crankcase is forcibly ventilated while controlling the flow rate of the blow-by gas by the intake negative pressure.

[0003] In the blow-by gas, there is an oil mist in which engine oil is atomized, so that it is not suitable for reburning as it is, and the consumption of engine oil increases. For this reason, before returning the blow-by gas to the intake system, it is necessary to separate the oil mist in the blow-by gas, and an oil droplet separating device called an oil trapper, an oil separator or the like is provided. As such an oil trapper, various types are known, and an external oil trapper (shown in FIG. 5) mounted on the outside of an engine block and a built-in oil trapper housed in a cylinder head cover are provided. A type of oil trapper (not shown) is known.

As the above-mentioned oil trapper, a so-called cyclone type trapper is widely used. This is configured, for example, as shown in FIG. 5, in which blow-by gas is introduced from an inlet port IP into a cyclone chamber (centrifugal separation chamber) CC, and performs a swirling motion from a central outlet passage OP via a hose HS. And discharged outside the room, and is sucked into the intake system of the internal combustion engine. At this time, the oil mist in the blow-by gas is separated by the centrifugal force generated at the time of the turning motion, and is collected in the oil reservoir along the wall surface of the cyclone chamber CC.

[0005]

However, in the above-described oil trapper, blow-by gas is not supplied to the outlet passage OP.
When the oil is discharged through, the oil attached to the outer wall of the outlet passage is caught on the inner wall side of the outlet passage, and is mixed into the blow-by gas by the swirling flow of the blow-by gas in the outlet passage,
There is a phenomenon that the air is directly sucked into the intake system.

In particular, when the outlet passage OP is connected to a portion separated by a hose, the outer diameter of the outlet passage OP is generally set so as to match the inner diameter of the hose (about 10 mm in diameter). It is a target. Therefore, the exit passage O
The inner diameter of P will be smaller than the inner diameter of the hose (for example, about 7 mm). Therefore, the flow velocity of the blow-by gas flowing in the outlet passage OP becomes large, and the oil mist in the blow-by gas is caught in the outlet passage OP before being sufficiently separated by the swirling motion in the cyclone chamber CC, and a large amount of oil mist is generated. It is sucked into the intake system while remaining in the blow-by gas.

Therefore, the present invention provides a simple configuration and
An object of the present invention is to provide a cyclone-type oil trapper for an internal combustion engine that can separate oil mist in a fluid such as blow-by gas.

[0008]

In order to achieve the above object, an oil trapper for an internal combustion engine according to the present invention comprises a first cylindrical body having a cylindrical surface inside and defining a separation chamber, and a first cylindrical body formed at both ends. A second cylinder having an open end, wherein one of the open ends extends into the first cylindrical body and is opened and the other open end is opened outside the first cylindrical body; A body, and an inlet pipe having an inlet port formed in the first cylinder so as to open in a tangential direction of the cylindrical surface near one open end of the second cylinder; in the body, have a the other larger inner diameter than the inner diameter of the open end the inner diameter is gradually increased toward the open end of the one
To form an enlarged inner diameter portion which is open at one open end side, the one
Form a smooth inner surface from one open end to the other open end.
The fluid is introduced into the first cylinder from the inlet port, and is discharged out of the second cylinder via the separation chamber and the enlarged inner diameter portion.

The inner diameter of the second cylindrical body may be gradually increased from the intermediate portion toward the one opening end, and this portion may constitute an enlarged inner diameter portion. Alternatively, a first tapered portion, a large-diameter first cylindrical portion, a second tapered portion, and a small-diameter second tapered portion extend from one open end side of the second cylindrical body to the other open end side. Forming a cylindrical part,
The enlarged inner diameter portion may be configured by a portion excluding the second cylindrical portion. At this time, it may be joined to the first cylinder at the position of the first cylinder, or may be joined to the first cylinder at the position of the second cylinder.

[0010]

In the oil trapper for an internal combustion engine according to the present invention, the inlet port is connected to, for example, a crankcase of the internal combustion engine, and the other open end of the second cylinder is connected to the intake port of the internal combustion engine. Connected to the system. As a result, the blow-by gas in the crankcase is tangentially introduced into the separation chamber from the inlet port, and the second blow-by gas is swirled.
Is discharged from one open end of the cylindrical body toward the other open end, and is sucked into the intake system of the internal combustion engine. The centrifugal force is applied to the oil mist in the blow-by gas by the turning motion at this time, the oil mist is separated along the inner wall surface of the separation chamber, and the separated oil is discharged outside the first cylinder. In this case, when the blow-by gas is discharged from one opening end of the second cylinder toward the other opening end, the separated oil is caught in the second cylinder due to the presence of the enlarged inner diameter portion. Can be suppressed to such an extent that can be prevented. The separated oil discharged outside the first cylinder can be separately returned into the internal combustion engine.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the oil trapper for an internal combustion engine according to the present invention will be described below with reference to the drawings. FIGS. 1 and 2 relate to an embodiment of the present invention and show a cyclone type oil trapper of an engine block external type. As shown in FIG. 2, for example, two parts made of synthetic resin are combined.
That is, the main body 1 including the first cylindrical body according to the present invention, and the outlet pipe 2 including the second cylindrical body according to the present invention, in which a part of the outlet pipe 2 extends into the main body 1. The two are joined together.

The main body 1 is a substantially cylindrical body, one opening end 1a having a small diameter and the other opening end 1b having a large diameter, and a tapered portion 1c formed on the opening end 1a side. The opening end 1b of the main body 1 extends in the radial direction and is formed with a flange portion 1f. An inlet pipe 5 is formed integrally with the main body 1 on the opening end 1b side, and an inlet port 5a is opened in a tangential direction of an inner cylindrical surface of the main body 1.

On the other hand, the outlet pipe 2, as shown in FIG. 2, is a cylindrical body having a flange 3 integrally formed at an intermediate portion. The flange portion 3 has a flange portion 3f, which is closely attached to the flange portion 1f of the main body 1. Outlet pipe 2 as shown in FIG.
Inside, the cylindrical portion 2c having an inner diameter larger than the inner diameter of the open end 2b and the first and second tapered portions 2 are opened on the open end 2a side.
d, 2e are formed, and the enlarged inner diameter portion 12 is formed by these.

When the outlet pipe 2 is joined to the main body 1, a separation chamber 11 is formed on the opening end 1 a side of the main body 1, and an enlarged inner diameter portion 12 is formed in the outlet pipe 2. The separation chamber 11 is connected to a crankcase (not shown) and an intake system (not shown) of the internal combustion engine via an inlet pipe 5 and an outlet pipe 2, respectively, and communicates with the outside via an open end 1a. It is composed of In this embodiment, since the hose 6 is connected to the outlet pipe 2 as shown in FIG. 1, the inner diameter of the open end 2b is restricted by the inner diameter of the hose 6, but the outlet pipe 2 is enlarged. The inner diameter of the inner diameter portion 12 is set to be large independently of the inner diameter of the hose 6.

In the oil trapper of the present embodiment having the above-described structure, the inlet pipe 5 is connected to the crankcase of the internal combustion engine through a hose (not shown), and the outlet end 2b of the outlet pipe 2 is connected to the opening end 2b. The hose 6 is connected through a hose 6 to an intake system of the internal combustion engine. Then, blow-by gas in the crankcase is tangentially introduced into the separation chamber 11 from the inlet port 5a, and makes a revolving motion in the same chamber from the open end 2a of the outlet pipe 2 to the open end 2b via the enlarged inner diameter portion 12. And is sucked into the intake system of the internal combustion engine through the hose 6.
The centrifugal force is applied to the oil mist in the blow-by gas by the swirling motion at this time, the oil mist is separated along the inner wall surface of the separation chamber 11, and the separated oil is discharged downward from the opening end 1a.

In this case, when the blow-by gas is discharged from the open end 2a of the outlet pipe 2 in the direction of the open end 2b, the flow rate of the blow-by gas in the enlarged inner diameter portion 12 is low. And the separation oil attached to the outer wall of the outlet pipe 2 is prevented from being caught on the inner wall side. The separated oil thus taken out is returned to an oil pan (not shown) via, for example, a rubber hose (not shown).

FIGS. 3 and 4 relate to another embodiment of the present invention, in which outlet pipes 22, 32 having different shapes from the outlet pipe 2 of the embodiment of FIG. 1 are provided. That is, the outlet pipe 22 in the embodiment of FIG. 3 is formed such that the inner diameter gradually increases from the middle part of the outlet pipe 22 where the flange portion 23 is formed to the large-diameter opening end 22a. An enlarged inner diameter portion is formed at the inner diameter gradually increasing portion. On the other hand, the outlet pipe 32 in the embodiment of FIG. 4 has a flange portion 33 formed in a cylindrical portion 32c corresponding to the cylindrical portion 2c in the embodiment of FIG. 1, and has a cylindrical portion 32c and tapered portions 32d and 32e. An enlarged inner diameter portion is configured.

[0018]

Since the present invention is configured as described above, the following effects can be obtained. That is, the oil trapper for an internal combustion engine of the present invention has one open end in the first cylinder.
Extends and opens and the other open end opens outside the first cylindrical body
A second tubular body arranged as an inner diameter toward the open end of the one possess the other larger inner diameter than the inner diameter of the open end
An enlarged inner diameter portion that gradually increases and opens on the one opening end side is formed , and is slid from the one opening end to the other opening end.
Since it is formed on the inner surface of the kana and configured to introduce a fluid into the first cylinder from the inlet port and discharge the fluid to the outside of the second cylinder through the separation chamber and the enlarged inner diameter portion, the second cylinder is formed. The flow rate in the body can be reduced, and the oil mist can be reliably separated with a simple structure.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an oil trapper for an internal combustion engine according to one embodiment of the present invention.

FIG. 2 is an exploded perspective view of an oil trapper for an internal combustion engine according to one embodiment of the present invention.

FIG. 3 is a longitudinal sectional view showing a part of an oil trapper for an internal combustion engine according to another embodiment of the present invention.

FIG. 4 is a longitudinal sectional view showing a part of an oil trapper for an internal combustion engine according to still another embodiment of the present invention.

FIG. 5 is a schematic configuration diagram of a conventional cyclone type oil trapper.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main body (1st cylinder) 2 Outlet pipe (2nd cylinder) 3 Flange part 5 Inlet pipe 11 Separation chamber 12 Enlarged inner diameter part 22 Outlet pipe 23 Flange part 32 Outlet pipe 33 Flange part

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-294510 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F01M 13/04 B04C 5/12

Claims (1)

(57) [Claims] 1. A first cylindrical body having a cylindrical surface inside and defining a separation chamber, and open ends at both ends, one open end of which extends into the first cylindrical body to open. The other open end is the first
A second cylinder disposed so as to open out of the cylinder, and an inlet port formed in the first cylinder so as to open in a tangential direction to the cylindrical surface near one open end of the second cylinder. with an inlet pipe formed with, on the second cylindrical body, on the one open end it has a larger inner diameter than the inner diameter of the other opening end
The inner diameter is gradually increased to form an enlarged inner diameter portion opening at the one open end side toward the other open from the open end of the one
It is formed on the smooth inner surface up to the mouth end, so that fluid is introduced into the first cylinder from the inlet port, and is discharged out of the second cylinder through the separation chamber and the enlarged inner diameter portion. An oil trapper for an internal combustion engine, comprising: