WO2014103443A1

WO2014103443A1 - Oil separator

Info

Publication number: WO2014103443A1
Application number: PCT/JP2013/074960
Authority: WO
Inventors: 山崎　伸司; 玄哉竹田
Original assignee: 三桜工業株式会社
Priority date: 2012-12-26
Filing date: 2013-09-10
Publication date: 2014-07-03
Also published as: JP2014125929A; JP5508650B1

Abstract

Provided is a centrifugal oil separator which is compact, has a high degree of freedom of layout, and can furthermore achieve high performance in oil separation. This oil separator is provided with: a horizontally-placed tubular casing (11) which defines a separator chamber (12) and forms a gas inlet (14) through which an oil-containing gas is introduced into one end of the separator chamber; a pipe (15b) which is arranged in the axial center of the tubular casing and which defines a passage through which gas from which oil has been separated is discharged to outside of the separator chamber; and a spiral fin (17) which is formed in a spiral shape and which, by the outer periphery part thereof abutting the inner surface of the separator chamber and the inner peripheral part thereof being fitted onto the outer periphery of the pipe, defines a spiral passage inside of the separator chamber.

Description

Oil separator

The present invention relates to an oil separator. More particularly, the present invention relates to a compact centrifugal oil separator suitable for an engine blow-by gas reduction device.

For example, in an automobile engine, a blow-by gas reduction device is installed, and an oil separator is installed in the blow-by gas recirculation system. As the oil separator, there is a centrifugal oil separator that swirls the blow-by gas, contacts the blow-by gas with the peripheral wall of the separator chamber by centrifugal force, and thereby separates the oil contained in the gas (for example, Patent Document 1).
By the way, in such a centrifugal oil separator, a cylindrical casing that forms a swirling flow is installed vertically (in a state where the axis is set up in a vertical direction). For this reason, a large installation space is required in the vertical direction, and there are cases where it cannot be installed due to layout restrictions. Further, when the flow rate of blow-by gas is small, the centrifugal force necessary for oil separation is not generated. For this reason, there is a problem that the oil separation performance is deteriorated.
On the other hand, there is a baffle plate type oil separator provided with an adjusting mechanism for changing the opening amount of the ejection hole in order to maintain a constant flow rate of blow-by gas flowing in the separator chamber for the purpose of increasing oil separation efficiency and the like ( For example, Patent Document 2).
In the baffle plate type oil separator disclosed in Patent Document 2, a plurality of ejection holes are provided in the partition wall (baffle plate), and at least one ejection hole is provided in a state where the pressure difference between the upstream side and the downstream side is small. When the pressure is opened and the pressure difference becomes large, the other ejection holes are sequentially opened. And by setting it as such a structure, while making the flow velocity of the gas in a separator chamber constant, oil separation efficiency is improved, and also when the flow volume of blow-by gas is large, the pressure loss is suppressed low.
However, in the oil separator disclosed in Patent Document 2, an opening / closing member (block) is slidably contacted along a baffle plate having a plurality of ejection holes as an opening amount adjusting mechanism, and the opening / closing member is ejected by a spring. The gas flow rate adjusting mechanism is configured by energizing in the direction of closing the hole. Therefore, not only the structure is complicated, but also the flow rate is controlled by the number of ejection holes, that is, the number of opened ejection holes, so the control is digital and the flow rate can be controlled smoothly. It wasn't.

JP-A-11-42444 JP 2011-163226 A

The present invention has been made in view of the various circumstances of the background art described above, and provides a centrifugal oil separator that is compact, has a high degree of freedom in layout, and provides high oil separation performance. The purpose is to do.
Another object of the present invention is to provide a centrifugal oil separator that has a simple structure and that can smoothly control the flow rate and maintain a low pressure loss even when the gas flow rate is large. And

In order to achieve the above object, the present invention provides the oil separator described in the following [1] to [6].
[1] A separator chamber is defined, a horizontal cylindrical casing having a gas introduction hole for introducing an oil-containing gas at one end of the separator chamber, and an axial center of the cylindrical casing are arranged to separate oil And a pipe that defines a passage for discharging the generated gas to the outside of the separator chamber, and an inner peripheral portion is fitted to the outer periphery of the pipe so that the outer peripheral portion is in contact with the inner surface of the separator chamber. A spiral fin that defines a spiral passage in the separator chamber, and an oil mixed gas is introduced from the gas introduction hole to generate a swirling flow by passing through the spiral passage. The oil is separated from the oil mixed gas by centrifugal force, and the gas from which the oil has been separated is discharged from the tip of the pipe to the outside of the separator chamber through the pipe passage. It characterized the door, the oil separator.
[2] The oil separator according to [1], wherein an oil discharge groove is formed on the inner bottom surface of the horizontal cylindrical casing substantially parallel to the spiral fin.
[3] The oil separator according to [2], wherein an end portion of the oil discharge groove is communicated with the gas introduction hole.
[4] The spiral fin is formed of an elastic material, one end of the spiral fin is fixed in the vicinity of the gas introduction hole, and the other part is disposed to be extendable and contractible in the axial direction of the pipe. A spiral passage is defined in the separator chamber, and the spiral fin is expanded and contracted by using a pressure change caused by an increase or decrease in the flow rate of the gas passing through the spiral passage to change the cross-sectional area of the spiral passage. The oil separator according to [1], wherein the flow rate of the gas flowing through the gas passage is controlled.
[5] A check valve is interposed between the pipe and a valve body that is aligned with the axial center of the pipe and is urged to oppose the gas discharge direction. [1] Oil separator as described in 1.
[6] The horizontal cylindrical casing is installed in a ceiling portion of a cylinder head cover, the gas introduction hole is opened in the cylinder head cover, and the other end of the pipe is connected to an intake pipe. The oil separator according to [5].

In the oil separator according to the present invention described in [1], a spiral passage is defined by a spiral fin in a horizontal cylindrical casing, and a swirl flow is forcibly generated in the introduced oil mixed gas. belongs to. Therefore, it is compact and has a high degree of freedom in layout as compared with a conventional centrifugal oil separator that is placed vertically. Further, even when the gas flow rate is small, high oil separation performance can be obtained.
In addition, according to the oil separator according to the present invention of [2], the separated oil is collected by dropping into a groove formed on the inner bottom surface of the horizontal cylindrical casing and discharged through the groove. Is done. Therefore, re-scattering of the separated oil is prevented.
In addition, according to the above-described [3] oil separator according to the present invention, the separated oil discharge port shares the gas introduction hole. Therefore, the structure is simple.
In the oil separator according to the present invention [4], the gas flow rate control mechanism is formed by forming the helical fins of an elastic material and fitting the pipes so as to expand and contract. Therefore, the structure is very simple, the oil separation performance is high, and even when the gas flow rate is large, the flow rate can be controlled smoothly and the pressure loss can be kept low.
Further, according to the oil separator according to the present invention [5], the check valve is integrally incorporated. Therefore, even if the pressure on the separator chamber side becomes negative with respect to the pressure on the gas discharge side, there is no possibility that the gas flows backward.
In addition, according to the above-described [6] oil separator according to the present invention, a compact engine blow-by gas reduction device can be configured.

FIG. 1 is an exploded perspective view conceptually showing an embodiment of an oil separator according to the present invention.
FIG. 2 is an enlarged cross-sectional view of a portion along line AA in FIG.
FIG. 3 is a longitudinal sectional view of the oil separator of the present embodiment shown in FIG. 1 and shows a state in which the spiral fins are contracted.
FIG. 4 is an enlarged view of the check valve portion of the oil separator according to the present embodiment shown in FIG. 1, and is a partially enlarged sectional view showing a closed state of the check valve.
FIG. 5 is an enlarged view of the check valve portion of the oil separator according to the present embodiment shown in FIG. 1, and is a partially enlarged sectional view showing the opened state of the check valve.
FIG. 6 is a longitudinal sectional view of the oil separator of the present embodiment shown in FIG. 1 and shows a state in which the spiral fins are extended.

Hereinafter, an oil separator according to the present invention will be described in detail based on the embodiments shown in the drawings.
As shown in FIG. 1, the oil separator 10 of the present embodiment is integrally installed on a ceiling portion of a cylinder head cover 1 made of synthetic resin. The cylinder head cover 1 is formed with a cylindrical casing 11 that is open on one side, that is, with its axis oriented in the horizontal direction. The cylindrical casing 11 defines a separator chamber 12, and an oil discharge groove 13 is formed over almost the entire length of the inner bottom surface thereof as shown in FIG. Further, as shown in FIG. 3, a blow-by gas introduction hole 14 that opens into the cylinder head cover 1 is formed at the end of the oil discharge groove 13. The oil discharge groove 13 is communicated with the blow-by gas introduction hole 14.
Further, as shown in FIG. 3, the horizontal cylindrical casing 11 has a valve chamber 15a in the axial center portion. A pipe 15b communicating with the valve chamber 15a is extended on one side, and a housing 15 having a connection portion 15c to which the hose 2 is attached is inserted on the other side. A groove 15d is formed in the circumferential direction on the outer peripheral surface of the housing 15, and an O-ring 16 is attached to the groove 15d. The O-ring 16 provides a seal between the housing 15 and the cylindrical casing 11.
A spiral fin 17 is fitted on the pipe 15b. One end of the spiral fin 17 is solidified near the base end of the pipe 15b, that is, in the vicinity of the blow-by gas introduction hole 14, and the other part is fitted to be stretchable along the pipe 15b. The spiral fins 17 are made of synthetic resin, metal or the like, have elasticity in the axial direction, and are formed so as to maintain an appropriate distance between the

fin walls

17a and 17a.
Further, as shown in FIG. 4, a valve body 18 is arranged in the valve chamber 15 a of the housing 15. The valve body 18 is urged by a spring 19 and is brought into contact with the valve seat 18a on the open end surface of the pipe 15b, thereby forming a check valve 20.
The hose 2 is connected to the connection portion 15 c of the housing 15. The oil separator 10 is connected to an intake passage or the like of an intake pipe (not shown) via the hose 2.
In the oil separator 10 configured as described above, the valve body 18 is opened as shown in FIG. 5 by the negative pressure of the intake pipe, that is, the differential pressure acting on the valve body 18. Then, as shown in FIG. 3, blow-by gas (shown by dotted lines) is introduced into the separator chamber 12 through the blow-by gas introduction hole 14, and the spiral defined by the spiral fins 17 and the inner wall of the cylindrical casing 11. The passage 15f is introduced into the pressure chamber 12a defined by the fin wall 17a at the tip of the spiral fin 17 and the tip of the pipe 15b through the cylindrical passage 15e, and further formed in the axis of the pipe 15b of the housing 15. Then, it reaches the valve chamber 15a, and is guided to an intake pipe (not shown) through a passage 15g of the connecting portion 15c.
Meanwhile, the blow-by gas is swirled by the spiral fins 17, and the blow-by gas is brought into contact with the inner peripheral surface of the cylindrical casing 11 by centrifugal force, whereby the oil contained in the gas is separated. The separated oil falls into the oil discharge groove 13, passes through the oil discharge groove 13, and is returned from the blow-by gas introduction hole 14 into the cylinder head cover 1.
By the way, when the differential pressure increases and the flow rate of blow-by gas increases, the pressure in the spiral passage 15e increases. Then, the spiral fins 17 are expanded corresponding to the pressure, as shown in FIG. When the spiral fin 17 is extended, the space between the

fin walls

17a and 17a expands, and the flow path cross-sectional area increases accordingly. Therefore, the flow rate of blow-by gas is thereby maintained constant, and high oil separation performance is always obtained. Further, the pressure loss can be kept low even when the flow rate of blow-by gas is large.
When the pressure on the intake passage side becomes higher than the pressure in the separator chamber 12, the valve body 18 of the check valve 20 is closed by the urging force of the spring 19, as shown in FIG. Is done.
Although the embodiments of the oil separator according to the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the technical idea of the present invention described in the claims. Variations and changes are possible. For example, the present invention can be applied not only to an engine but also to other devices and equipment.

The oil separator according to the present invention is a centrifugal oil separator that is compact, has a high degree of freedom in layout, and can obtain high oil separation performance, and is particularly installed in a blow-by gas recirculation system of an automobile engine. It can be suitably used as an oil separator.

DESCRIPTION OF SYMBOLS 1 Cylinder head cover 2 Hose 10 Oil separator 11 Cylindrical casing 12 Separator chamber 12a Pressure chamber 13 Oil discharge groove 14 Blow-by gas introduction hole 15 Housing

15a Valve chamber 15b Pipe

15c Connection part 15d Groove 15e, 15f, 15g Passage 16 O-ring 17 Spiral Fin 17a Fin wall 18 Valve element 18a Valve seat 19 Spring 20 Check valve

Claims

A separator chamber is defined, a horizontal cylindrical casing having a gas introduction hole for introducing an oil-containing gas at one end of the separator chamber, and a gas separated from oil disposed at the axial center of the cylindrical casing. A pipe that defines a passage for discharging to the outside of the separator chamber and a spiral shape, and an inner peripheral portion is fitted to the outer periphery of the pipe so that the outer peripheral portion is in contact with the inner surface of the separator chamber. A spiral fin that defines a spiral passage in the separator chamber, an oil mixed gas is introduced from the gas introduction hole, and a swirling flow is generated by passing through the spiral passage. The oil is separated from the oil mixed gas, and the gas from which the oil has been separated is discharged from the end of the pipe to the outside of the separator chamber through the pipe passage. Wherein an oil separator.
2. The oil separator according to claim 1, wherein an oil discharge groove is formed on an inner bottom surface of the horizontal cylindrical casing substantially parallel to the spiral fin. 3.
The oil separator according to claim 2, wherein an end portion of the oil discharge groove is communicated with the gas introduction hole.
The spiral fin is formed of an elastic material, one end of the spiral fin is fixed in the vicinity of the gas introduction hole, and the other part is disposed to be extendable and contractible in the axial direction of the pipe. A spiral passage is defined, and the spiral fin is expanded and contracted using a pressure change caused by an increase or decrease in the flow rate of the gas passing through the spiral passage to change the cross-sectional area of the spiral passage. 2. The oil separator according to claim 1, wherein the flow rate of the flowing gas is controlled.
2. The check valve according to claim 1, wherein a check valve is interposed in the pipe so that a valve body is aligned with an axial center of the pipe and is urged to oppose the gas discharge direction. Oil separator.
The horizontal cylindrical casing is installed in a ceiling portion of a cylinder head cover, the gas introduction hole is opened in the cylinder head cover, and the other end of the pipe is connected to an intake pipe. Item 6. The oil separator according to Item 5.