JPH0625624Y2 - Blow-by gas oil separator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION "Industrial Application Field" The present invention relates to a blow-by gas oil separation device.

[Conventional technology]

In order to prevent air pollution, an engine is equipped with a blow-by gas reduction device that returns blow-by gas to the intake system without releasing it into the atmosphere, but since blow-by gas contains oil, However, if the blow-by gas is simply returned to the intake system, the oil will be taken away by the blow-by gas. When the oil is taken away, firstly, the oil consumption amount increases, and secondly, problems such as deposits being accumulated in the intake system occur. Therefore, in order to prevent the occurrence of such a problem, the conventional engine always includes the blow-by gas reducing device and the oil separating device. The oil separator is a device for separating oil from blow-by gas.

As a prior art document disclosing an oil separation device for blow-by gas, for example, a device in which oil is separated from the blow-by gas by a baffle plate (Shokai Sho 60-39718, JP-A 60-192821),
There is a filter (Practical Application No. 57-81415) in which oil is separated by a porous filter. FIG. 6 shows, as an example, a vertical sectional view of a conventional oil separation device in which oil is separated by a baffle plate.

In FIG. 6, 11 is a baffle plate, and arrow A represents the flow of blow-by gas. The blow-by gas from which oil has been separated by the baffle plate 11 is discharged to the intake system from the blow-by gas outlet 23 through the blow-by gas passage 22 and the hose 24.

[Problems to be solved by the device]

The conventional oil separation device has a problem that the oil may be carried away by the blow-by gas to the intake system. This is for the following reason.

First, even if the oil is separated by the baffle plate or the filter, when the blow-by gas amount becomes large, the separated oil may be mixed with the blow-by gas again and carried away.

Secondly, in FIG. 6, only blow-by gas should flow in the blow-by gas passage 22, but in reality,
The oil that could not be separated or the oil that was mixed into the blow-by gas again after separation as described above becomes liquid and flows along the wall surface of the passage. Because it was sometimes taken away. For this reason, in the oil separation device as shown in FIG. 6, there is a case where the blow-by gas outlet 23 side is inclined so as to be upward so as to have an oil returning function by the weight of the oil itself. It was not easy to return the oil to the air intake system, and it was not possible to sufficiently reduce the amount of oil taken out of the intake system.

The present invention has been made in view of the above problems of the conventional technology, and its technical problem is to use a flow of blow-by gas to actively discharge oil from the blow-by gas passage. To reduce the amount of oil carried away by blow-by gas.

[Means for Solving the Problems]

In order to achieve this technical problem, the following measures are taken in the present invention.

That is, the blow-by gas oil separator according to the present invention is an oil trapping the oil at the bottom of the blow-by gas passage due to the stepped portion protruding from the bottom of the blow-by gas passage between the oil separation chamber and the blow-by gas outlet. A trap portion, an oil reservoir chamber connected in parallel below the blow-by gas passage by being connected to a bottom portion of the oil trap portion and a stepped portion downstream side of the blow-by gas passage, and a bottom portion of the oil reservoir chamber And an oil control means for allowing only a flow in a direction from the inside to the outside of the oil reservoir chamber.

[Action]

In the present invention, since the oil trap portion utilizing the stepped portion projecting from the bottom surface of the blow-by gas passage is provided in the middle of the blow-by gas passage, the oil flowing in liquid form on the bottom surface of the blow-by gas passage is stepped portion. The trapped oil is trapped by its own weight because the bottom of the oil trap part is connected to an oil storage chamber provided below the blow-by gas passage. To fall.

At that time, since the oil reservoir is also connected downstream of the stepped portion of the blowby gas passage and in parallel with the blowby gas passage, part of the blowby gas flows into the oil reservoir together with the trapped oil. , Through the oil reservoir to the blow-by gas passage. Thus, the trapped oil is pushed into the oil storage chamber by the blow-by gas flow in addition to the spontaneous fall due to its own weight.

The oil control means provided at the bottom of the oil sump chamber allows only the flow in the direction from the inside to the outside of the oil sump chamber. The blow-by gas outside the oil sump chamber is discharged to the outside through the oil control means and is prevented from flowing back into the oil sump chamber by the oil control means.

〔Example〕

FIG. 1 is a vertical cross-sectional view of a blow-by gas oil separator according to an embodiment of the present invention.

In FIG. 1, 1 is a cylinder head cover and 2 is a cylinder head. The cylinder head cover 1 is mounted on the cylinder head 2. Cylinder head 2
A camshaft 3 for driving an intake / exhaust valve of the engine is rotatably attached to. A timing belt pulley 4 around which a timing belt (not shown) is wound is attached to the tip of the camshaft 3.

A large number of baffle plates 11 are provided inside the cylinder head cover 1. FIG. 2 is a bottom view of the cylinder head cover of FIG. As can be seen from FIG. 2, the baffle plates 11 are alternately arranged on the left and right.

Returning to FIG. 1, 12 is an oil supply port for supplying oil. An oil filler cap 13 is screwed onto the oil filler port 12.

A partition plate 14 is attached to the lower surface of the baffle plate 11, and blow-by gas inlets 15 are provided on the left and right of the partition plate 14. An oil separation chamber 21 is formed inside the cylinder head cover 1 by the partition plate 14.

The blow-by gas, which has collided with the baffle plate 11 in the oil separation chamber 21 to separate the oil, is discharged from the blow-by gas outlet 23 through the blow-by gas passage 22 to the intake system of the engine through the hose 24. The arrow A represents the flow of blow-by gas in the oil separation chamber 21 and the blow-by gas passage 22.

Reference numeral 25 represents an inlet of the blow-by gas passage 22. An oil trap portion 31 is provided in the middle of the blow-by gas passage 22.
Is provided. In the oil trap section 31,
The stepped portion 32 is formed such that the effective flow passage cross-sectional area of the blow-by gas passage 22 once becomes large and becomes smaller again on the downstream side.
Is provided. In this embodiment, since the stepped portion 32 is made by utilizing the plate thickness of the blow-by gas outlet pipe 39, the stepped portion 32 extends from the inner peripheral wall surface of the oil trap portion 31 to the center of the blow-by gas passage 22. It is shaped so as to project toward.

An oil storage chamber 33 is formed below the oil trap portion 31. The oil reservoir chamber 33 and the bottom portion of the oil trap portion 31 located on the upstream side of the stepped portion 32 are connected by a bypass inlet passage 34. Further, downstream of the stepped portion 32, the oil reservoir chamber 33 and the blow-by gas passage 22 are connected by a bypass outlet passage 35. Therefore, the oil reservoir chamber 33 is connected in parallel to the blow-by gas passage 22, and the by-pass passage 36 is formed by bypassing the stepped portion 32. The bypass outlet passage 35 is provided with an orifice 41 for adjusting the amount of blow-by gas flowing through the bypass outlet passage 35.

The bottom of the oil reservoir 33 is closed by a bottom plate 42, and an oil return hole (not shown) for returning oil is formed in the bottom plate 42. Oil that goes out from the oil reservoir 33 is allowed in the oil return hole.
A non-return valve 43 is attached to prevent incoming blow-by gas.

FIG. 3 is a top view of the check valve of FIG. 1, and FIG. 4 is of FIG.
It is a IV-IV sectional view.

In FIGS. 3 and 4, reference numeral 43 indicates the entire check valve. Further, 44 is a valve body, and 45 is an oil hole formed in the valve body 44. As can be seen from FIG. 4, an umbrella valve 46 is attached to the valve body 44, and the oil hole 45 is closed from the outside of the oil reservoir 33 by the umbrella portion of the umbrella valve 46.
Therefore, in the check valve 43, the oil flowing from the oil reservoir chamber 33 (arrow X) through the oil hole 45 is passed as shown by the arrow X, but the oil reservoir chamber 33 is shown by the arrow Y.
Blow-by gas that tries to enter is blocked.

In FIG. 2, 12 is an oil supply port, 22 is a blowby gas passage, 25 is an inlet of the blowby gas passage 22, 4
2 is a bottom plate, 43 is a check valve, 39 is a blow-by gas outlet pipe, and 24 is a hose. Reference numeral 15 is a blow-by gas inlet. As can be seen from FIG. 2, the blow-by gas passage 22 is provided so as to contact one of the left and right walls of the cylinder head cover 1 and extend in the axial direction of the cylinder head cover 1. In FIG. 2, the partition plate 14 (see FIG. 1) attached below the baffle plate 11 is omitted.

The operation of this embodiment will be described.

In FIG. 1, when the blow-by gas flows through the blow-by gas passage 22, oil is flowing in liquid form at the bottom of the blow-by gas passage 22. In the present embodiment, since the oil trap portion 31 is provided, the oil flowing in a liquid state collides with the stepped portion 32 and is dammed, and enters the bypass inlet passage 34 by its own weight. At the same time, blow-by gas also collides with the stepped portion 32, but the bypass inlet passage 34
Since the bypass outlet passage 35 and the bypass outlet passage 35 form a bypass passage 36, part of the blow-by gas enters the bypass inlet passage 34 and exits from the bypass outlet passage 35. An arrow B is attached to this blow-by gas. Thus, the oil is pushed into the bypass inlet passage 34 by blow-by gas in addition to the natural fall due to its own weight, so that most of the oil flowing at the bottom of the blow-by gas passage 22 falls into the oil reservoir 33. . As described above, the blow-by gas that has entered the bypass inlet passage 34 and entered the oil reservoir chamber 33 returns to the blow-by gas passage 22 again from the bypass outlet passage 35, but at this time, the effect of sucking out the blow-by gas due to the negative pressure is obtained. Therefore, the blow-by gas entering the bypass inlet passage 34 more positively pushes the oil into the bypass inlet passage 34.

When a certain amount of oil is stored in the oil storage chamber 33, the check valve 43 is opened by its own weight and the oil returns to the cylinder head 2.

As can be seen from the above description, in the present embodiment, even if the oil flows through the blow-by gas passage 22, the oil is not only caused by its own weight but also actively dropped into the oil reservoir chamber 33 by the blow-by gas flow. Gas does not remove oil.

Since the flow of the blow-by gas (arrow B) flowing through the bypass passage 36 is weak, the blow-by gas does not carry away the oil in the oil reservoir 33.

In this embodiment, the check valve 43 is provided in the oil return hole (not shown) at the bottom of the oil sump chamber 33 because the blow-by gas containing oil mist enters the oil sump chamber 33 through the oil return hole. This is to prevent it. The check valve 43 corresponds to the oil control means in the present invention.

FIG. 5 is a vertical cross-sectional view of a blow-by gas oil separator according to a second embodiment of the present invention.

In the structure shown in FIG. 5, instead of using a check valve, an oil sump 51 is provided in the cylinder head 2 and an oil sump chamber 33 is provided.
The oil return pipe 52 is hung from the oil return hole 49, and the tip of the oil return pipe 52 is dipped in the oil in the oil sump 51. Even with this,
The oil can be returned from the oil reservoir 33, and the blow-by gas never flows backward from the oil return pipe 52. In the case of the second embodiment, the oil return pipe 52 and the oil sump 51 correspond to the oil control means in the present invention.

Since the other points in FIG. 5 are exactly the same as those in the first embodiment, only the reference numerals are attached to the drawing and further description is omitted.

The specific embodiment of the present invention has been described above, but the present invention is not limited to this embodiment, and various embodiments are included within the scope of the utility model registration claim. For example, the oil trap portion 31 of the first and second embodiments has a stepped portion 32 in which the effective flow passage cross-sectional area is wider than that of the blow-by gas passage 22. It is only necessary to partially block the flow so that a part of the blow-by gas and the oil on the bottom of the blow-by gas passage enter the bypass inlet passage 34.
The blow-by gas passage 22 may be narrowed by providing only the stepped portion 32 without expanding the effective flow passage cross-sectional area of the blow-by gas passage 22. Even if the oil return pipe 52 is not immersed in the oil sump 51 as shown in FIG. 2, the oil return pipe 52 does not have the same oil return as in the Japanese Patent Application No. 56-059954 filed on April 23, 1981. Alternatively, the tip of the pipe 52 may be bent into a U shape to collect oil in that portion, thereby preventing the reverse flow of blow-by gas.

[Effect of device]

According to the present invention, the oil flowing on the bottom of the blow-by gas passage is positively discharged by the blow-by gas flow to the oil reservoir chamber where the blow-by gas flow is weak, so that the oil flowing on the bottom of the blow-by gas passage to the intake system is discharged. Carry-out is reduced.

Further, since the oil in the oil reservoir is discharged to the outside through the oil control means having a one-way valve function without passing through the blow-by gas passage, when the oil in the oil reservoir is discharged, the oil in the blow-by gas enters the blow-by gas again. It is also prevented from being mixed.

Therefore, it is possible to significantly reduce the amount of oil taken away by the blow-by gas.

[Brief description of drawings]

1 is a vertical cross-sectional view of an oil separation device for blow-by gas according to a first embodiment of the present invention, FIG. 2 is a bottom view of the cylinder head cover of FIG. 1, and FIG. 3 is of FIG. FIG. 4 is a top view of the check valve, FIG. 4 is a sectional view taken along line IV-IV of FIG. 3, and FIG. 5 is a longitudinal sectional view of an oil separation device for blow-by gas according to a second embodiment of the present invention. FIG. 1 is a vertical sectional view of a conventional blow-by gas oil separation device. 11 …… Baffle plate 21 …… Oil separation chamber 22 …… Blow-by gas passage 23 …… Blow-by gas outlet 31 …… Oil trap portion 32 …… Stepped portion 33 …… Oil storage chamber 34 …… Bypass inlet passage 35 …… Bypass outlet passage 43, 52, 51 (oil control means) 43 ... Check valve 51 ... Oil sump 52 ... Oil return pipe

Claims (1)

[Scope of utility model registration request] 1. An oil trap portion for trapping oil on the bottom surface of the blow-by gas passage by a stepped portion protruding from the bottom surface of the blow-by gas passage between the oil separation chamber and the blow-by gas outlet, and a bottom portion of the oil trap portion. An oil reservoir chamber connected in parallel below the blow-by gas passage by being connected to the downstream side of the stepped portion of the blow-by gas passage, and from the inside of the oil reservoir chamber provided at the bottom of the oil reservoir chamber. An oil separation device for blow-by gas, comprising: an oil control unit that allows only a flow in the direction toward the outside.