JPH10317940A - Gas/liquid separating device for blowby gas - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate adverse effects on the performance of an engine through reliable separation of oil and suppression of wear of its cylinders with a gas/ liquid separating device, and lessen the load on the engine through simplified structure and reduced weight of the separating device effected at smaller cost. SOLUTION: A blowby gas passage 13 is provided so as to be communicated from a crankcase with a breather chamber 401 defined by a head cover 3, and a blowby gas inflow port 14 is formed between the blowby gas passage 13 and the breather chamber 401 so as to regulate the inflow direction of the blowby gas that is led by the blowby gas passage 13 into the breather chamber 401. That constitution accelerates the blowby gas flowing into the breather chamber 401, optimizes the flowing direction of the gas, and ensures oil separation through oil separation and oil drop collection due to differences in specific gravity. That constitution also simplifies the structure of the cover 3 for its smaller manufacturing cost and reduced weight to lessen the engine load.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a gas-liquid separation device for blow-by gas.

[0002]

2. Description of the Related Art First, an outline of a blow-by gas will be described. A mixture of air and fuel in the combustion chamber (including a small amount of combustion gas) during the compression and explosion processes of the engine
Leaks from the gap between the inner wall of the cylinder and the piston ring and accumulates in the crankcase. The mixture of air and fuel leaked into the crankcase is called blow-by gas. Since most of the blow-by gas is unburned gas, the blow-by gas is introduced into the intake system, returned to the combustion chamber, and recombusted from the viewpoint of fuel economy. Also,
Since there is a large amount of lubricating oil in the crankcase, this lubricating oil mixes with the blow-by gas. As described above, when the blow-by gas mixed with the lubricating oil is recombusted, carbon is generated and the cylinder is worn, or the combustion is incompletely performed, which adversely affects the engine performance. Before the oil is introduced into the intake system, it is necessary to separate lubricating oil (hereinafter referred to as oil) from the blow-by gas.

[0003] In a conventional oil separating device (gas-liquid separating device for blow-by gas), as shown in FIG. 7, a blow-by gas passage 1 communicating with a crank chamber is provided on a side surface of a cylinder head 2. Blow-by gas passage 1 is head cover 3
A blow-by gas passage 5 is provided in the head cover 3 so as to communicate with the breather chamber 4 formed by the above-mentioned condition, and the inflow direction from the blow-by gas inlet 6 into the breather chamber 4 is not restricted. To allow the blow-by gas to flow as indicated by the arrow. Then, in order to efficiently separate oil from the blow-by gas in the breather chamber 4, a detour is introduced into the breather chamber as disclosed in, for example, JP-A-8-177443. A guide wall is provided. And blow along this detour guide wall
By flowing the by-gas, the flow path of the blow-by gas is lengthened, and the oil is separated from the blow-by gas by collision with the bypass guide wall.

As shown in FIG. 8, a blow-by gas passage 1 provided on a side surface of a cylinder head 2 is opened to a cam chamber in which a cam 8, a cam shaft 9 and a cam spring 10 are located. The inlet 7 is provided, and in a state in which the inflow direction is not regulated, the blow-by gas flowing into the cam chamber as shown by the arrow contacts the cam 8, the camshaft 9, and the cam spring 10, and the inflow direction is not regulated. It flows into the breather chamber 4 as shown by the arrow. Also, JP-A-8-177443 discloses that
There is disclosed an apparatus in which an oil-proof cover is provided on a head cover positioned below a breather chamber to prevent blow-by gas from entering the cam chamber.

[0005]

In the conventional blower gas separation apparatus described above, as shown in FIG. 7, the blow-by gas is supplied to the blower chamber in a state where the flow direction into the blower chamber is not regulated. If the oil is allowed to flow in, the oil cannot be sufficiently separated in the breather chamber.
An equivalent of a detour guide wall is required in the room. Therefore, the structure inside the breather chamber becomes complicated, which is not preferable because it becomes an expensive head cover, and the weight increases by that much, which increases the engine load, which is not preferable.

Further, as shown in FIG. 8, when the blow-by gas is allowed to flow into the cam chamber without restricting the flow direction,
Since a large amount of oil is mixed in the blow-by gas, when the blow-by gas comes into contact with a cam, a camshaft or a cam spring, the mixed oil is scattered and oil is separated from the blow-by gas. If it enters the breather chamber without oil being separated in the cam chamber, the amount of oil to be separated in the breather chamber increases,
In order to separate the oil, the structure inside the breather chamber must be further complicated, which results in an expensive head cover, which is not preferable. In addition, the weight is increased by that much, and the engine load is increased, which is not preferable.

The present invention regulates the flow direction of the blow-by gas, thereby ensuring the separation of oil, reducing cylinder wear and preventing the engine performance from being adversely affected. With a simple structure, the weight is reduced by reducing the load on the engine, and an inexpensive blower
It is intended to provide a device for separating bigas.

[0008]

Means for solving the above problems are as follows from the description of claim 1 according to the present invention.
A blow-by gas passage communicating from the crank chamber to the breather chamber formed by the head cover is provided, and the blower gas is regulated so as to regulate the flow direction of the blow-by gas flowing from the blow-by gas passage into the breather chamber. A blow-by gas inlet is provided between the gas passage and the breather chamber.

[0009] Next, the means to be grasped from the second aspect of the present invention is to provide an oil drain hole in which the direction of the blow-by gas inflow hole is blown from above the breather chamber to the bottom of the breather chamber. It is characterized by having flowed in toward.

A third aspect of the present invention provides a blow-by gas passage communicating from the crank chamber to the cam chamber of the head cover, and the flow direction of the blow-by gas into the cam chamber is in the cam chamber. A blow gas inlet is provided between the blow gas passage and the cam chamber so as to avoid a rotating part.

Next, how the problem is solved by the present invention as understood from the description of each claim will be described. First, according to the present invention as understood from the first aspect, a blow-by gas passage communicating from the crank chamber to the breather chamber formed by the head cover is provided, and the blow-by gas flows from the blow-by gas passage into the breather chamber. Blow
By providing a blow-by gas inflow hole between the blow-by gas passage and the breather chamber so as to regulate the flow direction of the by-gas, the flow rate of the blow-by gas flowing into the breather chamber is increased, In addition, the flow direction is optimized, and the oil is separated by the difference in specific gravity and the oil droplets are collected to separate the oil.

Next, according to the present invention, the direction of the blow-by gas inflow hole can be determined by changing the direction of the blow-by gas from above the breather chamber to the bottom of the breather chamber. Since the gas flows toward the holes, the blow-by gas collides with the bottom of the breather chamber at a high flow rate, the oil having a large specific gravity collides with the bottom and is captured, and the blow-by gas having a small specific gravity is Flows as it is and separates from oil, and
Since the blow-by gas flows toward the oil drop hole, the separated oil is recovered from the oil drop hole and does not mix again with the blow-by gas.

Next, according to the present invention, the blow-by gas passage communicating from the crank chamber to the cam chamber of the head cover is provided to prevent oil from entering from portions other than the crank chamber. I do. A blow gas inflow hole is provided between the blow-by gas passage and the cam chamber so that the direction of the blow-by gas flowing into the cam chamber avoids the rotating portion in the cam chamber. Even if the spilled oil is scattered by a cam, a camshaft, or the like, it does not mix again with the blow-by gas.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention as understood from the description of the above claims will be described. First, the embodiment of the present invention grasped from the description of claim 1 is shown in FIG.
As shown in FIG. 1, a blow-by gas passage 13 communicating from the crank chamber 11 to a breather chamber 401 formed by the head cover 3 is provided, and as shown in FIG.
A blow-by gas inlet hole 14 is provided between the blow-by gas passage 13 and the breather chamber 401 so as to regulate the flow direction of the blow-by gas flowing from the blower gas into the breather chamber 401.

Next, according to an embodiment of the present invention as understood from the description of claim 2, as shown in FIG. 1, the direction of the blow-by gas The oil flows into the oil drain hole 16 opened in the bottom 15 of the breather chamber 401 from above.

Next, according to the embodiment of the present invention as understood from the third aspect, as shown in FIG. 6, a blow-by gas passage 13 communicating from the crank chamber 11 to the cam chamber of the cylinder head 2 is provided. As shown in FIG.
A blow gas inflow hole 18 is provided between the blow-by gas passage 13 and the cam chamber 17 so that the inflow direction of the by-gas avoids rotating parts such as the cam 8 and the cam shaft 9 in the cam chamber 17.

Hereinafter, embodiments of the present invention will be described in more detail. In FIG. 6, the breather chamber 4 is divided by a partition wall 21 into two breather chambers 401 and 402. Among them, the blow-by gas which is separated into gas and liquid in the breather chamber 401 is PC
The blow-by gas, which has been separated into gas and liquid in the breather chamber 402, is introduced to the upstream side of the throttle valve through the V valve. Has become.

The breather chamber 401 is connected to the crank chamber 11 by a blow-by gas passage 13, and sucks blow-by gas leaked into the crank chamber 11 due to the negative pressure of the manifold. On the other hand, a passage communicating with the cam chamber 17 is provided on the breather chamber 402 side.
There is provided an oil drop passage 19 communicating with the
The blow-by gas in the oil drop passage 19 and the cam chamber of the cylinder head 2 is sucked by the negative pressure of the intake manifold. An oil gauge seat 23 is fitted into the top opening of the blow-by gas passage 13, and the top opening of the blow-by gas passage 13 is closed.

FIG. 1 is an enlarged view of the breather chamber 401 side. 1 and 3, the blow-by gas passage 13 has a breather chamber 401 and a cylinder block 12 (FIG. 6).
And a passage isolated from the cylinder head 2, and a blow-by inflow hole 14 is formed in the partition wall 20 provided in the breather chamber 401. Thus, by providing the blow-by gas passage 13 in an isolated state, the ventilation in the crank chamber 11 is efficiently performed by effectively utilizing the negative pressure of the manifold, and the blow-by gas (Bubbles)
To prevent deterioration of lubrication performance of lubricating oil,
Energy loss due to a decrease in lubrication performance can be eliminated, and a decrease in engine performance can be prevented. In addition, since oil does not enter from portions other than the crankcase 11, the breather chamber
Oil separation within 401 can be facilitated. Also,
By increasing the flow rate of the blow-by gas in the blow-by gas passage 13, the cooling effect of the blow-by gas is enhanced, so that oil droplets contained in the blow-by gas are condensed and the oil is separated from the blow-by gas. It can be performed to some extent in the bigas passage 13.

In FIG. 5, a substantially central portion of the inside of the head cover 3 is partitioned by the partition wall 21 so as to be separated from the breather chamber 401.
402 is formed. The volume of the breather chamber 402 is made somewhat larger than that of the breather chamber 401 so that gas-liquid separation is possible. A blow-by gas passage 13 is provided at an edge of the head cover 3 forming the breather chamber 401, and an oil drain hole 16 is provided near the partition wall 21 and a blow-by gas passage 13 is provided. A PCV valve 22 is provided at a corner of the side surface of the head cover 3 provided with 13 so as to extend the residence time of the blow-by gas and sufficiently perform gas-liquid separation.

The blow-by gas inflow hole 14 is provided as shown in FIG.
As shown in FIG. 5, the blow-by gas flows in the direction of the arrow from above the breather chamber 401 toward the bottom 15, and flows in the direction of the arrow toward the oil drain hole 16 as shown in FIG. It is open. Further, as shown in FIG. 5, the outflow direction of the blow-by gas from the blow-by gas inlet 14 and the outflow direction of the blow-by gas from the PCV valve 22 are opposite to each other.

As described above, by making the flow of the blow-by gas reverse, the flow direction of the blow-by gas flowing from the blow-by gas inflow hole 14 is changed at the bottom 15 and collides with the partition wall 21. Then, it is reversed and flows out of the PCV valve 22. Also, as shown in FIG. 1, the ceiling of the head cover 3 is lowered by H1 at the partition wall 21, and when the head is inverted at the partition wall 21, it is guided by the ceiling of the head cover 3 and is forcibly and strongly inverted. . Further, as can be seen from FIG. 1, an oil drop hole 16 is formed in a portion where the oil is separated by inverting the partition wall 21.

Next, the operation will be described. 1 and 6, since the blow-by gas passage 13 communicating from the crank chamber 11 to the breather chamber 401 formed by the head cover 3 is provided, there is no mixing of oil from portions other than the crank chamber 11. . Then, the blow-by gas passage 13 and the blower chamber 4 are controlled so as to regulate the inflow direction of the blow-by gas flowing from the blow-by gas passage 13 into the breather chamber 401.
By providing the blow-by gas inflow hole 14 between the first and the second 01, the flow velocity of the blow-by gas flowing into the breather chamber 401 is increased, the flow direction is optimized, and the oil due to the specific gravity difference is increased. The oil is separated by separating oil and collecting oil droplets.

As shown in FIG. 1, the direction of the blow-by gas inflow hole 14 is changed to the oil drop hole 16 formed by blowing the blow-by gas from above the breather chamber 401 to the bottom 15 of the breather chamber 401. As a result, the blow-by gas collides with the bottom 15 of the breather chamber 401 at a high flow rate, and the oil having a large specific gravity is separated by inertia and collides with the bottom 15 to be captured. Gas flows as it is and separates from the oil, and since the blow-by gas flows into the oil drop hole 16, the separated oil is collected from the oil drop hole and returned to the blow-by gas again. There is no mixing.

Further, the oil drop hole 16 is provided at a portion where the blow-by gas is reversed by the partition wall 21 (in the vicinity of the partition wall 21), and the PCV valve 22 is provided on the side wall of the head cover 3 provided with the blow-by gas passage 13. By providing in the corner of
When the flow direction is changed along the bottom 15, the blow-by gas that has flowed in at an increased flow rate from the blow-by gas inflow hole 14 separates oil having a large specific gravity by inertial force, and
The separated oil adheres to the bottom 15 and is trapped, and is further separated from the partition wall.
When the oil is reversed at 21, the oil is also separated by the inertial force, and the separated oil adheres to the partition wall 21 and the ceiling of the head cover 3, is captured, and is collected from the oil drop hole 16.

At the same time, the oil droplets contained in the blow-by gas are cooled and aggregated when the blow-by gas collides with the bottom 15 and the partition wall 21 at a high flow rate, and the aggregated oil is separated by inertia. Collected. And FIG.
As shown in FIG. 5, since the bottom 15 provided with the oil drop hole 16 is concave, the oil blown off by the inertial force falls into the concave, and the separated oil can be efficiently collected.

Next, the embodiment shown in FIG. 2 will be described. In the embodiment shown in FIG. 2, a blow-by gas passage 13 is provided in the same manner as shown in FIG. 1, and communicates with a cam chamber 17 of the head cover 3 in which a cam 8 is provided. A blow-by gas inlet 18 is provided.
This blow-by gas passage 13 is provided with a cam 8 as shown in FIG.
2 and is located above the camshaft 9 as shown in FIG. 2 and is further directed upward in the direction of the breather chamber 401. The blow-by gas flowing into the cam chamber 17 is guided to the breather chamber 401 through the hole 18 'formed in the bottom 15 without contacting the cam 8 and the cam shaft 9. The cam spring 10 is connected to the camshaft 9
The cam spring 10 does not come into contact with the blow-by gas. In this embodiment, the bottom 15 may be omitted.

Next, the operation will be described. 2 and 6, the cam chamber of the head cover 3 is moved from the crank chamber 11.
Since the blow-by gas passage 13 communicating with 17 is provided, there is no mixing of oil from portions other than the crank chamber 11. Further, since the cam chamber 17 having a large volume is used as a breather chamber, it is possible to sufficiently separate oil. The direction in which the blow-by gas flows into the cam chamber 17 is the cam 8 in the cam chamber 17.
Since the blow gas inlet hole 18 is provided between the blow-by gas passage 13 and the cam chamber 17 so as to avoid the cam shaft 9, the oil once separated in the cam chamber 17 is removed by the cam 8 and the cam shaft 9. Even if it is scattered, it does not mix again with the blow-by gas. Further, as shown in FIG. 3, by providing a blow-by gas passage 13 between the cams 8, a cam chamber is formed.
The oil separated in 17 is not scattered by the cam 8, and even if scattered by the cam shaft 9, the scatter does not reach far, so that the oil does not mix into the blow-by gas.

In the embodiment shown in FIGS. 1 and 2, the blow-by gas passage 13 is provided independently of the cylinder block 12 and the cylinder head 2.
Since the manifold negative pressure is effectively used through the breather chamber 401 to efficiently ventilate the inside of the crank chamber 11 and reliably perform gas-liquid separation in the breather chamber 401, the blow into the lubricating oil is prevented. -It is possible to prevent mixing of bigas (bubbles) to prevent a decrease in lubrication performance of the lubricating oil, to prevent energy loss due to a reduction in lubrication performance, and to prevent a decrease in engine performance.

[0030]

According to the present invention, which is understood from the detailed description of the present invention based on the first aspect, as described in detail above, the communication from the crank chamber to the breather chamber formed by the head cover is established. A blow-by gas passage is provided between the blow-by gas passage and the breather chamber so as to regulate the flow direction of the blow-by gas flowing into the breather chamber from the blow-by gas passage. Make a hole,
Increasing the flow rate of the blow-by gas flowing into the breather chamber,
In addition, since the direction of the flow is optimized, oil is separated by specific gravity difference and oil is collected by collecting oil droplets, so the head cover structure is simplified and an inexpensive blow-by gas separation device is used. And at the same time, reduce the weight to reduce the engine load.

Next, according to the present invention, which is understood from the detailed description of the present invention based on the second aspect, the direction of the blow-by gas inflow hole is determined by the direction of the blow-by gas from above the breather chamber. Blow-by gas collides with the bottom of the breather chamber at a high flow rate, and oil with a high specific gravity collides with the bottom and is captured. At the same time, the blow-by gas having a low specific gravity flows as it is and separates from the oil, and since the blow-by gas flows into the oil drop hole, the separated oil is collected from the oil drop hole and the blow-by gas is removed. The structure of the head cover can be simplified, an inexpensive blow-by gas separation device can be used, the weight can be reduced, the engine load can be reduced, and oil can be separated more reliably. of Reduce Worn, it can be made to not adversely affect engine performance.

Next, according to the present invention, which is understood from the detailed description of the present invention based on the third aspect, a blow-by gas passage communicating from the crank chamber to the cam chamber of the head cover is provided. Blow gas flows between the blow-by gas passage and the cam chamber so as to prevent oil from being mixed in from parts other than the chamber and to prevent the blow-by gas from flowing into the cam chamber in the direction of rotation of the cam chamber. A hole is provided so that even if oil once separated in the cam chamber is scattered by the cam or camshaft, it does not mix again with the blow-by gas. By reducing the number of parts and improving the assemblability, the weight is reduced and the engine load is reduced, and furthermore, the separation of oil is ensured to reduce cylinder wear, and the engine performance is not adversely affected. It can be so.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a main part of an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view showing a main part of another embodiment of the present invention.

FIG. 3 is a plan view of the cylinder head in FIGS. 1 and 2;

FIG. 4 is a longitudinal sectional view taken along line AA of FIG. 3;

FIG. 5 is a rear view of the head cover in FIG. 1;

FIG. 6 is a longitudinal sectional view showing the entire engine to which the blow-by gas separation device in FIG. 1 is applied.

FIG. 7 is a longitudinal sectional view showing a main part of a conventional example.

FIG. 8 is a longitudinal sectional view showing a main part of a conventional example.

[Explanation of symbols]

 2 Cylinder head 3 Head cover 4 Breather chamber 11 Crank chamber 12 Cylinder block 13 Blow-by gas passage 14 Blow-by gas inlet 16 Oil drain hole 17 Cam chamber 18 Blow-by gas inlet 19 Oil drop passage 22 PCV valve

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Shoji Takeuchi 300 Takatsukacho, Hamamatsu-shi, Shizuoka Suzuki Co., Ltd.

Claims (3)

[Claims] 1. A blow-by gas passage communicating from a crank chamber to a breather chamber formed by a head cover is provided, and a flow direction of blow-by gas flowing from the blow-by gas passage into the breather chamber is regulated. Thus, a blow-by gas-liquid separation device characterized in that a blow-by gas inlet is provided between a blow-by gas passage and a breather chamber. 2. The direction of the blow-by gas inflow hole is adjusted by the blower.
2. The gas-liquid separation device for blow-by gas according to claim 1, wherein the by-gas flows from above the breather chamber toward an oil drop hole drilled at the bottom of the breather chamber. 3. A blow-by gas passage communicating from a crank chamber to a cam chamber of a head cover is provided.
A blow-by gas-liquid separation device, wherein a blow-gas inflow hole is provided between a blow-by gas passage and a cam chamber so that a flow direction of the by-gas is avoided from a rotating portion in the cam chamber.