JP2023072995A - Gas-liquid separator - Google Patents

Abstract

To prevent reduction of the amount of oil to be supplied from a gas liquid separation device to a lubrication portion of an internal combustion engine.SOLUTION: A gas liquid separation device 10 separates blow-by gas from oil L introduced from a crank case of an internal combustion engine. The gas liquid separation device 10 includes: an oil tank 12 storing the oil L to be supplied to a lubrication portion of the internal combustion engine; and a cylindrical gas liquid separator 11 accommodated in the oil tank 12. The oil tank 12 includes a discharge port 12h for discharging blow-by gas to the outside. The gas liquid separator 11 includes an extension part 25 extending from an end having a shorter distance to the discharge port 12h out of ends in the axial direction L1 toward the outer side of the gas liquid separator 11.SELECTED DRAWING: Figure 1

Description

The present invention relates to a gas-liquid separator.

Patent Literature 1 describes an oil tank that stores oil. The oil stored in the oil tank is supplied to lubricated parts of the internal combustion engine. Oil is introduced into the oil tank from the crankcase of the internal combustion engine.

JP-A-05-306611

The oil introduced from the crankcase to the oil tank may contain blow-by gas. Therefore, it has been considered to use a gas-liquid separator in which a gas-liquid separator is housed inside the oil tank. Gas-liquid separators separate blow-by gases from oil introduced from the crankcase of an internal combustion engine. The blow-by gas separated from the oil by the gas-liquid separator is discharged to the outside of the oil tank, for example, through a discharge port located in the oil tank.

Under conditions where centrifugal force acts on the gas-liquid separation device, such as when the vehicle is running, the oil level may tilt with respect to the oil level when the vehicle is stopped. When the oil surface inclines, the oil flows toward the outlet inside the oil tank. When oil leaks out of the oil tank through the outlet, the amount of oil supplied to the lubricated parts of the internal combustion engine decreases by the amount of the leaked oil.

A gas-liquid separation device that solves the above problems is a gas-liquid separation device that separates blow-by gas from oil introduced from a crankcase of an internal combustion engine, and stores oil that is supplied to lubricating parts of the internal combustion engine. A tank and a cylindrical gas-liquid separator housed in the oil tank, the oil tank having an outlet for discharging blow-by gas to the outside, and the gas-liquid separator It has an extending portion extending outward from the gas-liquid separator from one of the ends in the axial direction of the gas-liquid separator that is closer to the discharge port.

According to the above configuration, the extension portion can block the flow of oil toward the discharge port. Therefore, it is possible to suppress the oil from leaking out of the oil tank from the outlet. Therefore, the amount of oil supplied from the gas-liquid separation device to the lubrication parts of the internal combustion engine is less likely to decrease.

It is a cross-sectional view of the gas-liquid separation device. FIG. 2 is a cross-sectional view taken along line 2-2 of FIG. 1;

An embodiment of a gas-liquid separation device mounted on an internal combustion engine, which is a driving source of a vehicle, will be described below with reference to FIGS. 1 and 2. FIG.
<Basic configuration of gas-liquid separation device>
As shown in FIG. 1 , the gas-liquid separator 10 includes a gas-liquid separator 11 and an oil tank 12 . The oil L discharged from the gas-liquid separation device 10 is supplied to lubricated parts of the internal combustion engine. Note that the vertical direction in FIG. 1 is the direction of gravity.

Oil L containing blow-by gas is sucked from the crankcase of the internal combustion engine by the scavenging pump P1. The oil L sucked by the scavenging pump P1 is introduced into the gas-liquid separator 11 through the oil introduction pipe 31 . The gas-liquid separator 11 separates the blow-by gas from the oil L introduced from the crankcase of the internal combustion engine. The oil tank 12 stores oil L to be supplied to lubricated parts of the internal combustion engine. The oil tank 12 stores the oil L from which the blow-by gas is separated by the gas-liquid separator 11 . The oil L stored in the oil tank 12 is discharged from the oil tank 12 to the discharge passage 32 . The oil L discharged to the discharge passage 32 is pressure-fed to lubrication parts of the internal combustion engine by the feed pump P2. Unless otherwise specified, the following description regarding the position of the configuration of the gas-liquid separation device 10 is for the position when the vehicle is stopped on a horizontal plane.

<Configuration of oil tank>
The oil tank 12 accommodates the gas-liquid separator 11 . The oil tank 12 may have a first tank portion 13 and a second tank portion 14 . The first tank portion 13 has a rectangular box shape. The first tank portion 13 has a rectangular plate-like first wall 13a, a rectangular tubular second wall 13b, and a rectangular plate-like third wall 13c. The second wall 13b connects the edge of the first wall 13a and the edge of the third wall 13c. The oil introduction pipe 31 penetrates the second wall 13b and extends between the outside and the inside of the first tank portion 13 . The third wall 13c is located below the first wall 13a in the direction of gravity. A through hole 13h that penetrates the third wall 13c is located in the center of the third wall 13c. The direction in which the axis of the first tank portion 13 extends is called the axial direction L1.

The oil tank 12 is a dry sump type oil tank. The oil tank 12 has a discharge port 12h for discharging blow-by gas to the outside. The discharge port 12h is a circular hole penetrating through the first wall 13a of the first tank portion 13 . 12 h of discharge ports are located in the center of the 1st wall 13a.

A cylindrical discharge pipe 15 is connected to the first wall 13a. The discharge pipe 15 communicates with the inside of the first tank portion 13 through the discharge port 12h. The blow-by gas is discharged from the inside of the oil tank 12 to the discharge pipe 15 through the discharge port 12h. Blow-by gas is introduced into the intake passage of the internal combustion engine via the exhaust pipe 15 .

The second tank portion 14 is cylindrical with a bottom. The second tank portion 14 has a cylindrical tubular portion 14a and a circular plate-shaped bottom portion 14b. The axis of the tubular portion 14a extends in the axial direction L1. The axis of the first tank portion 13 may be positioned on the extension of the axis of the cylindrical portion 14a.

One end of the cylindrical portion 14a is called a first end 14c, and the other end is called a second end 14d. The bottom portion 14b is positioned so as to block the second end 14d with respect to the tubular portion 14a. The dimension in the radial direction of the tubular portion 14a increases from the second end 14d toward the first end 14c. The second tank portion 14 is positioned below the first tank portion 13 in the direction of gravity. A first end 14c of the tubular portion 14a is connected to a third wall 13c of the first tank portion 13 . The inside of the second tank portion 14 communicates with the inside of the first tank portion 13 via the through hole 13h of the third wall 13c.

In the oil tank 12, the bottom portion 14b of the second tank portion 14 is positioned at the bottom in the gravitational direction. The entire inside of the second tank portion 14 is filled with the oil L stored in the oil tank 12 . The oil L fills the lower portion of the inside of the first tank portion 13 in the direction of gravity. Other portions in the first tank portion 13 are not filled with the oil L. The liquid surface of the oil L is positioned inside the first tank portion 13 .

A discharge channel 32 communicates with at least one of the cylindrical portion 14a and the bottom portion 14b. The oil L inside the second tank portion 14 is introduced into the discharge passage 32 .
<Configuration of gas-liquid separator>
The gas-liquid separator 11 is tubular. The axis of the gas-liquid separator 11 is called separator axis L2. The separator axis L2 extends in the axial direction L1. The separator axis L2 may coincide with the axis of the first tank portion 13 . That is, the axial direction L1 corresponds to the axial direction of the gas-liquid separator 11 .

One end of the gas-liquid separator 11 is called a first open end 11a, and the other end is called a second open end 11b. The second open end 11b is positioned below the first open end 11a in the gravitational direction. The gas-liquid separator 11 increases in radial dimension from the second opening end 11b toward the first opening end 11a.

The first open end 11a has a shorter distance from the discharge port 12h than the second open end 11b. That is, the first open end 11a corresponds to the end of the gas-liquid separator 11 in the axial direction L1 that is closer to the discharge port 12h.

A discharge port 12h is positioned on the extension of the separator axis L2. Specifically, the center of the discharge port 12h is positioned on the extension of the separator axis L2. The inner diameter of the gas-liquid separator 11 at the first open end 11a is larger than the diameter of the discharge port 12h.

The gas-liquid separator 11 has an oil introduction hole 11h. The oil introduction hole 11h penetrates between the outer surface 11c and the inner surface 11d of the gas-liquid separator 11 . The outer surface 11 c of the gas-liquid separator 11 faces the inner surface of the second wall 13 b of the oil tank 12 . An end of an oil introduction pipe 31 is connected to the gas-liquid separator 11 . The oil introduction pipe 31 communicates with the inside of the gas-liquid separator 11 via the oil introduction hole 11h.

As shown in FIGS. 1 and 2 , the gas-liquid separator 11 is supported by the first tank portion 13 with a support plate 33 . The support plate 33 extends between the outer surface 11c of the gas-liquid separator 11 and the inner surface of the second wall 13b. Four support plates 33 are arranged inside the first tank portion 13 .

An internal pipe 21 extending in the axial direction L<b>1 is positioned inside the gas-liquid separator 11 . The inner tube 21 is cylindrical. The axis of the inner tube 21 may coincide with the separator axis L2. One end of the internal pipe 21 is exposed to the outside of the gas-liquid separator 11 from the first open end 11 a of the gas-liquid separator 11 . The other end of the internal pipe 21 is exposed to the outside of the gas-liquid separator 11 from the second open end 11b of the gas-liquid separator 11 . The outer peripheral surface of the internal pipe 21 is separated from the inner surface 11 d of the gas-liquid separator 11 . Thus, the internal space of the gas-liquid separator 11 is defined by the inner surface 11 d of the gas-liquid separator 11 and the outer peripheral surface of the internal pipe 21 .

The inner tube 21 has four first supports 22 . The internal pipe 21 is supported by the gas-liquid separator 11 by a first support portion 22 . The first support portion 22 is shaft-shaped and protrudes from the outer peripheral surface of the inner tube 21 . The first support portion 22 extends from between both ends of the inner tube 21 . Assuming that the end portion of the first support portion 22 connected to the internal pipe 21 is the proximal end, the distal end of the first support portion 22 is fixed to the inner surface 11 d of the gas-liquid separator 11 . The first support portions 22 are separated from each other in the circumferential direction of the inner tube 21 .

The inner tube 21 is supported on the support plate 33 by the second support portion 23 . The second support portion 23 has a plate shape extending from the outer peripheral surface of the inner tube 21 . The second support portion 23 has an annular shape when viewed from the axial direction L1. The second support portion 23 extends from the end of the internal pipe 21 exposed to the outside of the gas-liquid separator 11 from the second open end 11b. An outer peripheral edge of the second support portion 23 is fixed to four support plates 33 . Thereby, the internal pipe 21 is supported by the first tank portion 13 via the support plate 33 .

The second support portion 23 is separated from the second opening end 11b of the gas-liquid separator 11 in the axial direction L1. Thus, an oil discharge portion 11j, which is a space defined by the second opening end 11b and the second support portion 23, is positioned below the gas-liquid separator 11 in the axial direction L1. The internal space of the gas-liquid separator 11 communicates with the outside of the gas-liquid separator 11 via the oil discharge portion 11j.

The gas-liquid separator 11 has an extension 25 . The extending portion 25 is connected to the end portion of the outer surface 11c of the gas-liquid separator 11 on the discharge port 12h side. The extending portion 25 extends from the outer surface 11c of the gas-liquid separator 11 toward the inner surface of the second wall 13b. The extending portion 25 has a plate shape extending orthogonally to the axial direction L1. The extending portion 25 has an annular shape when viewed from the axial direction L1. The extending portion 25 extends outward from the gas-liquid separator 11 from the first open end 11 a of the gas-liquid separator 11 . The outer peripheral edge of the extending portion 25 is separated from the inner surface of the first tank portion 13 . An outer peripheral edge of the extending portion 25 may be fixed to the support plate 33 .

<Flow of oil and blow-by gas>
Next, the flow of the oil L and the blow-by gas in the gas-liquid separation device 10 will be described.

As shown in FIG. 1, the oil L is introduced into the gas-liquid separator 11 from the crankcase of the internal combustion engine via the oil introduction pipe 31 . This oil L contains blow-by gas. When the oil L is introduced into the gas-liquid separator 11, the oil L flows through the gas-liquid separator 11 through the oil introduction hole 11h. The flow of the oil L at this time is indicated by a two-dot chain line arrow in FIG. The oil L spirally flows inside the gas-liquid separator 11 from the first open end 11a toward the second open end 11b. Oil L flows around inner tube 21 .

Centrifugal force acts on the oil L while it flows through the gas-liquid separator 11 . The blow-by gas is separated from the oil L by this centrifugal force. The blow-by gas separated from the oil L by the gas-liquid separator 11 is discharged outside the gas-liquid separator 11 through the first open end 11 a of the gas-liquid separator 11 . This blow-by gas is introduced into the intake passage of the internal combustion engine via the exhaust pipe 15 . The flow of blow-by gas in the discharge pipe 15 is indicated by dashed arrows in FIG.

When the oil L flowing inside the gas-liquid separator 11 reaches the second opening end 11b, the oil L flows out into the first tank portion 13 through the oil discharge portion 11j. The oil L from which the blow-by gas is separated by the gas-liquid separator 11 is stored inside the oil tank 12 . If blow-by gas remains in the oil L stored inside the oil tank 12 , this blow-by gas is introduced from the oil tank 12 into the internal pipe 21 . The blow-by gas introduced inside the internal pipe 21 is introduced into the discharge pipe 15 after flowing through the inside of the internal pipe 21 . The oil L stored inside the oil tank 12 is supplied from the oil tank 12 through the discharge passage 32 to the lubrication parts of the internal combustion engine.

<Action>
Next, the operation of this embodiment will be described.
Under conditions where centrifugal force acts on the gas-liquid separation device 10, such as when the vehicle is running, the liquid level of the oil L may tilt with respect to the liquid level of the oil L when the vehicle is stopped. In particular, when the vehicle turns or the vehicle speed is rapidly accelerated or decelerated, the liquid level of the oil L inside the oil tank 12 may be greatly inclined. When the liquid surface of the oil L inclines, the oil L flows inside the oil tank 12 toward the discharge port 12h. Due to such a flow, the oil L may leak from the oil tank 12 to the discharge pipe 15 via the discharge port 12h.

In this embodiment, the gas-liquid separator 11 has an extending portion 25 extending outward from the gas-liquid separator 11 from the first open end 11a. Therefore, when the liquid surface of the oil L is tilted with respect to the liquid surface of the oil L when the vehicle is stopped, the extension portion 25 prevents the flow of the oil L toward the discharge port 12h inside the oil tank 12. can be blocked by As a result, it is possible to prevent the oil L from leaking into the discharge pipe 15 through the discharge port 12h.

<effect>
According to the above embodiment, the following effects can be obtained.
(1) The extending portion 25 can block the flow of the oil L toward the discharge port 12h. Therefore, it is possible to prevent the oil L from leaking out of the oil tank 12 from the outlet 12h. Therefore, the amount of oil L supplied from the gas-liquid separation device 10 to the lubricated parts of the internal combustion engine is less likely to decrease.

(2) If the oil L leaks from the oil tank 12 to the discharge pipe 15, the oil L may be introduced into the intake passage of the internal combustion engine via the discharge pipe 15. When this oil L reaches the combustion chamber from the intake passage of the internal combustion engine, there is a risk that white smoke will be generated as the oil L burns. According to the above embodiment, the leakage of the oil L from the oil tank 12 to the discharge pipe 15 can be suppressed, so the generation of white smoke caused by the leakage of the oil L can be suppressed.

<Change example>
The above embodiment can be implemented with the following modifications. The above embodiments and the following modifications can be combined with each other within a technically consistent range.

- The extending portion 25 does not have to be orthogonal to the axial direction L1. The extending portion 25 in this modification is inclined with respect to the extending portion 25 in the above embodiment.
- The extending portion 25 is not limited to having an annular shape when viewed from the axial direction L1. For example, the extending portion 25 may have a shape divided into a plurality of parts in the circumferential direction of the gas-liquid separator 11 . The divided portions of the extending portion 25 may be separated from each other in the circumferential direction of the gas-liquid separator 11 .

- The shape of the extending portion 25 is not limited to a plate shape. In short, the extending portion 25 may have any shape as long as it extends outward from the gas-liquid separator 11 from the first opening end 11a.
- The extending portion 25 may be in contact with the inner surface of the first tank portion 13 .

- The extending portion 25 may be arranged closer to the third wall 13c than the end portion of the outer surface 11c of the gas-liquid separator 11 on the discharge port 12h side. That is, in the present disclosure, the end portion of the gas-liquid separator 11 is not only the end portion in the strict sense, but also the portion from which the extension portion 25 extends, which reduces the inclination of the liquid surface of the oil L. This is a portion that can reduce the outflow of the oil L from the discharge port 12h.

L... Oil L1... Axial direction 10... Gas-liquid separator 11... Gas-liquid separator 12... Oil tank 12h... Discharge port 25... Extension part

Claims (1)

A gas-liquid separation device for separating blow-by gas from oil introduced from a crankcase of an internal combustion engine,
an oil tank that stores oil to be supplied to lubricated parts of the internal combustion engine;
a cylindrical gas-liquid separator housed in the oil tank,
The oil tank has an outlet for discharging blow-by gas to the outside,
The gas-liquid separator extends outwardly of the gas-liquid separator from one of the ends of the gas-liquid separator in the axial direction that is closer to the discharge port. A gas-liquid separator having a part.

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