JP2007138823A - Internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an internal combustion engine capable of improving recirculation performance of blow-by gas under low temperature condition. <P>SOLUTION: This engine is provided with a blow-by gas flow path 5 which is provided in a head cover 2 and in which blow-by gas flows, a first opening 5b provided on a wall surface of the head cover 2 and communicating to the blow-by gas flow path 5, a first chamber 8 capable of separating oil in the blow-by gas introduced from the first opening 5b, a gas liquid separating means 7 composed of a second chamber 9 communicating to the first chamber 8 via a bulkhead, a second opening 12b provided on a wall surface of the head cover introducing blow-by gas into the head cover 2 from the second chamber 9, and a blow-by gas recirculation path 12 provided inside of the head cover and supplying blow-by gas introduced in an intake system in the cylinder head from the second opening 12b. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an internal combustion engine.

Conventionally, as this type of internal combustion engine, a gas-liquid separation that separates oil mist in the blow-by gas at the upper part of the rocker cover is provided separately from the blow-by gas flow path that is formed in the rocker cover and into which the blow-by gas flows. Proposed devices have been proposed.
In this internal combustion engine, blow-by gas from which oil mist has been well separated by the gas-liquid separator is returned from the outlet pipe to the intake pipe side.
JP-A-8-158853

However, in such an internal combustion engine, blow-by gas is recirculated to the intake pipe by an external pipe such as a rubber hose connected to the outlet pipe, so that heat radiation or relatively low temperature air flows through the external pipe flows. Due to the cooling effect from the intake system, the moisture in the blow-by gas freezes, particularly at extremely low temperatures, and the blow-by gas recirculation performance deteriorates.
Further, the gas-liquid separation device provided on the upper part of the rocker cover separately from the blow-by gas flow path only separates the oil mist in the blow-by gas and has not been used at all.

  The present invention has been devised in view of the above-mentioned conventional problems, and is intended to improve blowby gas recirculation performance particularly at extremely low temperatures. In addition, lubricating oil can be simply injected using a gas-liquid separator. One of the purposes is to secure the structure, and further provides an internal combustion engine that can prevent the lubricating oil from scattering from the lubricating oil injection port to the outside even when the lubricating oil lid is forgotten. The claim 1 is an internal combustion engine including a blow-by gas recirculation device that recirculates blow-by gas to an intake system, the blow-by gas reduction device includes a blow-by gas flow path through which the blow-by gas provided in a head cover; A first opening as an inlet provided in the wall surface of the head cover communicating with the blow-by gas flow path, and the blow-by gas is introduced and introduced from the first opening. A gas-liquid separation means comprising a first chamber capable of separating oil in the blow-by gas and a second chamber communicating with the first chamber into which the blow-by gas from which the oil has been separated is introduced through a partition wall. A second opening as a lead-out port provided in a wall surface of the head cover for introducing the blow-by gas into the head cover from the second chamber, and a communication path communicating with the intake system formed in the cylinder head And a blow-by gas recirculation path provided inside the head cover for supplying the blow-by gas led out from the second opening to the communication path.

  Further, the second aspect of the present invention is that the blow-by gas flow path is formed so as to be able to separate oil in the blow-by gas.

  According to a third aspect of the present invention, the first opening and the second opening are formed on the upper surface of the head cover, and the gas-liquid separating means is disposed on the upper surface of the head cover.

  According to a fourth aspect of the present invention, the gas-liquid separation means controls the flow rate of the blow-by gas flowing from the first chamber into the second chamber, and the blow-by gas flows back from the second chamber to the first chamber. In other words, the first chamber and the second chamber communicate with each other through a control valve that prevents the above.

  A fifth aspect of the present invention is that the control valve is formed above the first chamber.

  According to a sixth aspect of the present invention, the upper surface of the head cover is formed with a third opening through which a lubricating oil can be injected via a chain chamber, and the gas-liquid separating means is arranged in a horizontal direction with respect to the third opening. Provided with a lubricating oil injection means formed with an injection port for injecting the lubricating oil at a position offset to the position, and an introduction path for introducing the lubricating oil injected from the injection port into the third opening is formed. It is.

  A seventh aspect of the present invention is that the gas-liquid separation means is formed by forming the second chamber using a part of the lubricating oil injection means.

The present invention relates to an internal combustion engine including a blowby gas recirculation device that recirculates blowby gas to an intake system, wherein the blowby gas reduction device includes a blowby gas passage provided inside a head cover and through which the blowby gas flows. A first opening serving as an inlet provided on the wall surface of the head cover communicating with the gas flow path, and a blow-by gas introduced from the first opening and an oil component in the introduced blow-by gas can be separated. A gas-liquid separation means comprising one chamber and a second chamber communicating with the first chamber into which the blow-by gas from which the oil has been separated is introduced via a partition; and from the second chamber to the inside of the head cover A second opening as a lead-out port provided in the wall surface of the head cover for introducing blow-by gas; and the intake system formed in the cylinder head; A blow-by gas is provided from the blow-by gas flow path by including a communication path through which the blow-by gas is led out from the second opening and a blow-by gas recirculation path provided in the head cover for supplying the blow-by gas to the communication path. It is introduced into the first chamber of the gas-liquid separation means through the first opening, and the oil component is separated in the first chamber and introduced into the second chamber. The blow-by gas that has flowed into the second chamber is led to the blow-by gas return path inside the head cover through the second opening, and is supplied from the blow-by gas return path to the intake system through the communication path formed in the cylinder head. .
In other words, blow-by gas can be supplied to the intake system using a flow path formed inside the internal combustion engine that is relatively hot without using external piping. As a result, blow-by gas is blown even at low temperatures, particularly at extremely low temperatures. It is possible to prevent the moisture in the gas from freezing, and to improve the reflux performance of the blow-by gas at a low temperature, particularly at a very low temperature.

  Further, the blow-by gas flow path is formed so as to be able to separate the oil content in the blow-by gas, whereby the oil content in the blow-by gas can be more effectively separated.

  In addition, the first opening and the second opening are formed on the upper surface of the head cover, and the gas-liquid separation means is disposed on the upper surface of the head cover. Even if oil accumulates in the gas flow path, it is possible to prevent the oil from entering the gas-liquid separation chamber.

  The gas-liquid separation means controls the flow rate of the blow-by gas flowing from the first chamber into the second chamber and prevents the blow-by gas from flowing back from the second chamber to the first chamber. Since the first chamber and the second chamber communicate with each other via a control valve, the flow rate of blow-by gas flowing from the first chamber to the second chamber can be controlled, and the blow-by gas can be controlled. It is possible to prevent the gas from flowing back from the second chamber to the first chamber.

  Further, the control valve is formed above the first chamber, so that the oil component in the blow-by gas can be more effectively separated and flow into the second chamber.

In addition, a third opening is formed on the upper surface of the head cover through which a lubricating oil can be injected via a chain chamber, and the gas-liquid separation means is at a position offset in the horizontal direction with respect to the third opening. Gas-liquid separation is provided by providing a lubricating oil injection means having an injection port for injecting the lubricating oil, and forming an introduction path for introducing the lubricating oil injected from the injection port into the third opening. Since the lubricating oil injection structure can be easily secured using the means, and the third opening and the lubricating oil injection port are offset in the horizontal direction, even if the lid of the lubricating oil injection port is forgotten to be attached, It is possible to prevent the lubricating oil from scattering from the lubricating oil inlet to the outside.
Further, in the internal combustion engine of this aspect, the gas-liquid separation means is formed by using a part of the lubricating oil injection means by forming the second chamber using a part of the lubricating oil injection means. Two chambers may be formed.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a schematic configuration diagram showing an outline of a configuration of an engine 1 as an internal combustion engine including a blow-by gas recirculation device according to an embodiment of the present invention.
As shown in the figure, the blow-by gas recirculation device of the embodiment has a blow-by gas passage 5 formed in the head cover 2 through which blow-by gas flowing in from a crankcase (not shown) flows, and oil content in the blow-by gas. A gas-liquid separation device 7 provided on the upper surface of the head cover 2 to be separated, and a blow-by gas that recirculates the blow-by gas from which oil has been separated by the gas-liquid separation device 7 to the communication passage 3 b communicating with the intake port 3 a of the cylinder head 3. And a reflux path 12. The engine 1 is placed horizontally so that the cylinder row direction is perpendicular to the vehicle longitudinal direction.

  As shown in the figure, the head cover 2 is formed with concave grooves 5a and 12a surrounded by a rib R standing on the back surface 2a, and a baffle plate 4 is installed at the lower end of the rib R as a flow path. The blowby gas flow path 5 and the blowby gas recirculation path 12 are configured. Further, an opening 5 b that communicates with the blow-by gas flow path 5 and an opening 12 b that communicates with the blow-by gas recirculation path 12 are formed on the upper surface of the head cover 2.

FIG. 2 is a rear view of the head cover 2 as viewed from the rear side, FIG. 3 is a route diagram showing a lubricating oil injection route, and FIG. 4 is an arrangement position of the gas-liquid separator 7 on the upper surface of the head cover 2. FIG.
As shown in FIG. 2, the blow-by gas channel 5 is formed so as to surround one of the insertion portions 30 into which the spark plug is inserted, and connects the insertion portion 30 and a part of the rib R with the rib R5. The blow-by gas flowing in from the inflow portion 100 is prevented from being guided to the opening 5b through the shortest path.

The blow-by gas recirculation path 12 includes a straight portion 12c extending in the cylinder row direction along the side surface of the head cover 2, and a connecting portion 12d communicating with the communication passage 3b.
The connecting portion 12d is formed in a boss portion 2d provided integrally with the flange portion 2c as a combined surface with the cylinder head 3 of the head cover 2, and is formed upward from the lower surface of the boss portion 2d. It consists of the direction hole 120, the connection hole 121 which connects the upward hole 120 and the linear part 12c, and the groove part 122 formed in the lower surface of the boss | hub part 2d which connects to the upward hole 120 and connects to the communicating path 3b. Has been. The groove portion 122 is formed substantially parallel to the cylinder row direction, and is configured as a flow path by the head cover 2 being attached to the cylinder head 3. In the embodiment, one groove portion 122 has two communication paths. It was supposed to communicate with 3b. That is, the blow-by gas can be recirculated to the four intake ports 3a by the two boss portions 2d.

  The head cover 2 is formed with a chain chamber lid 2e for covering the upper surface of a chain chamber 20 described later, and an opening 19 is formed in the chain chamber lid 2e. As shown in FIGS. 2 and 3, the opening 19 is located on the upper surface of the head cover 2 at a substantially central position with respect to the longitudinal direction of the vehicle, that is, among the cam sprockets 21 arranged in the chain chamber 20 (see FIG. Corresponding between the cam sprocket 21a which is the rotational direction side with respect to the vertical direction passing through the rotation center of the camps rocket 21a on the side receiving the chain from the cam sprocket 21a and the cam sprocket 21b on the side receiving the chain from the cam sprocket 21a. Formed in position.

As shown in FIG. 1, the gas-liquid separator 7 includes a main body portion 7 a that separates oil in blow-by gas, and a lid member 13 that is attached to the main body portion 7 a.
The main body portion 7a has a hollow portion 8a that is open at the bottom, a hollow portion 9a that is open at the bottom and is perpendicular to the cylinder row direction, that is, the front side direction of the vehicle, and a lower portion of the hollow portion 9a. A hollow portion 15a that is open at the bottom and open in the vehicle front side direction is formed in the same manner as the hollow portion 9a. The openings below the hollow portions 8a, 9a, and 15a communicate with the openings 5b, 12b, and 19, respectively. The head cover 2 is attached and fixed to the upper surface. In this state, the opening below the cavity 8a is closed by the upper surface of the head cover 2, and the first chamber 8 for separating the oil in the blowby gas is formed.

As shown in FIG. 3, the lid member 13 is composed of a flange 13a as a mounting portion to the main body portion 7a, and a protruding portion 13b protruding substantially perpendicularly from the flange 13a, and the protruding portion 13b is on the vehicle front side. It attaches to the main-body part 7a so that it may protrude in the direction substantially horizontal.
The protruding portion 13 b is formed with a lubricating oil injection port 18 to which the oil filler cap 16 is detachably attached via a packing 17, and an introduction path 15 opened to the flange 13 a communicating with the lubricating oil injection port 18. The introduction path 15 communicates with the cavity 15a with the lid member 13 attached to the main body 7a. That is, as shown in FIGS. 3 and 4, the lubricating oil injection port 18 and the opening 19 communicate with each other in a positional relationship that is offset in the vehicle longitudinal direction.
Further, the opening in the vehicle front side direction of the hollow portion 9a is closed by the flange 13a in a state where the lid member 13 is attached to the main body portion 7a, and the second chamber 9 for separating the oil content in the blow-by gas is configured. . The second chamber 9 communicates with the first chamber 8 via a PCV valve 10 provided at a position above the first chamber 8.

Next, the operation of the blow-by gas recirculation device configured as described above, particularly the operation when separating the oil in the blow-by gas and the operation when injecting lubricating oil will be described.
First, the operation | movement at the time of isolate | separating the oil component in blowby gas is demonstrated.
The blow-by gas that has flowed into the blow-by gas channel 5 from the inflow portion 100 is guided to the opening 5 b while bypassing the insertion portion 30. In this way, while the blow-by gas flowing in from the inflow portion 100 bypasses the insertion portion 30, the blow-by gas contacts the wall surface of the insertion portion 30 and the rib R so that the oil component is well separated. The blow-by gas guided to the opening 5b is introduced into the first chamber 8 from the opening 5b. At this time, the flow velocity of the blow-by gas is reduced, and the oil content in the blow-by gas is separated from the blow-by gas by its own weight. In the embodiment, the PCV valve 10 is disposed above the first chamber 8. As a result, the oil content in the blow-by gas can be more effectively separated.

The blow-by gas from which the oil has been separated in this way is prevented from flowing back into the first chamber 8 by the PCV valve 10, and the flow rate is adjusted and introduced into the second chamber 9, and the blow-by gas recirculation passage through the opening 12b. 12 is derived. The blow-by gas led out to the blow-by gas recirculation path 12 flows through the straight portion 12c, is led to the communication passage 3b through the connecting portion 12d, and is supplied from the communication passage 3b to each intake port 3a.
In this way, the inside of the crankcase (not shown) is used by using the respective passages (blowby gas passage 5, blowby gas recirculation passage 12, communication passage 3b) through which the blowby gas formed inside the engine 1 having a relatively high temperature flows. Since the blow-by gas leaked to the inside is recirculated, it is possible to prevent icing of moisture in the blow-by gas at a low temperature, particularly at a very low temperature.

Next, the operation at the time of injecting lubricating oil will be described.
Lubricating oil injected from the lubricating oil injection port 18 is introduced into the chain chamber 20 from the opening 19 through the introduction path 15, flows through the chain chamber 20, and is supplied to an oil pan (not shown). At this time, since the lubricating oil inlet 18 and the opening 19 are offset in the vehicle front-rear direction, even if the oil filler cap 16 is forgotten to be attached, the lubricating oil scatters from the lubricating oil inlet 18 to the outside. There is nothing. Further, the opening 19 is formed on the upper surface of the cylinder head cover 2 at a position corresponding to the space between the campus rocket 21a and the cam sprocket 21b that is on the rotational direction side with respect to the vertical direction passing through the rotation center of the campus rocket 21a. Therefore, it is possible to satisfactorily prevent the lubricating oil scattered by the rotation of the cam sprocket 21 a from flowing into the opening 19. Further, since the lubricating oil injection port 18 is arranged on the front side in the vehicle front-rear direction, the lubricating oil can be easily injected. In the embodiment, the reason why the lubricating oil is supplied to the oil pan through the chain chamber 20 is that the lubricating oil can be quickly supplied to the oil pan.

  According to the blow-by gas recirculation device of the embodiment described above, the blow-by gas leaked into the crankcase (not shown) flows into the blow-by gas flow path 5 formed in the head cover 2 and passes through the gas-liquid separator 7. After the oil is separated, the oil is recirculated to the intake port 3a through the blow-by gas recirculation path 12 and the communication path 3b. That is, since the blow-by gas is recirculated inside the engine 1 having a relatively high temperature without using an external pipe, it is possible to prevent water in the blow-by gas from icing even at a low temperature, particularly at a very low temperature. As a result, the reflux performance of blow-by gas can be improved. Moreover, since the blow-by gas passage 5 is guided to the opening 5b while bypassing the insertion portion 30, the oil component can be separated also in the blow-by gas passage 5, and the oil separation performance is further improved. In addition, since the second chamber 9 and the first chamber 8 of the gas-liquid separator 7 are communicated with each other at a position above the first chamber 8, the oil component can be more effectively separated by its own weight. . Further, since the openings 5b and 12b are formed on the upper surface of the head cover 2, even if a large amount of blow-by gas is generated and the lubricating oil is accumulated in the blow-by gas flow path 5, the lubricating oil is stored in the first chamber of the gas-liquid separation device 7. 8 can be prevented from entering.

  In addition, since the lubricating oil injection port 18 is formed in the lid member 13 of the gas-liquid separation device 7 so that the lubricating oil injection port 18 and the opening 19 are offset in the vehicle front-rear direction, the oil filler cap 16 is forgotten to be attached. However, the lubricating oil does not scatter from the lubricating oil inlet 18 to the outside. Further, the opening 19 is formed on the upper surface of the cylinder head cover 2 at a position corresponding to the space between the campus rocket 21a and the cam sprocket 21b that is on the rotational direction side with respect to the vertical direction passing through the rotation center of the campus rocket 21a. Therefore, it is possible to satisfactorily prevent the lubricating oil scattered by the rotation of the cam sprocket 21 a from flowing into the opening 19. Further, since the lubricating oil injection port 18 is arranged on the front side in the vehicle front-rear direction, the lubricating oil can be easily injected.

  In the blow-by gas recirculation device of the embodiment, the blow-by gas flow path 5 is shaped to guide the opening 5b while bypassing the insertion portion 30, but it is only necessary that the blow-by gas flowing from the inflow portion 100 can be guided to the opening 5b. The blow-by gas that has flowed in from the inflow portion 100 may be guided to the opening 5b in the shortest path, for example, linearly to the opening 5b.

  In the blow-by gas recirculation device of the embodiment, the blow-by gas flow path 5 is guided to the opening 5b while bypassing the insertion portion 30 as a shape for separating the oil content in the blow-by gas, but if the oil content in the blow-by gas can be separated, For example, the blow-by gas flow path 5 may be formed in a labyrinth shape.

  In the blow-by gas recirculation device of the embodiment, the openings 5b and 12b are formed on the upper surface of the head cover 2, but may be formed on the side surface of the head cover 2. In this case, the gas-liquid separator 7 may be attached and fixed to the head cover 2 so that the openings of the cavities 8a, 9a, and 15a communicate with the openings 5b, 12b, and 19, respectively.

  In the blow-by gas recirculation device of the embodiment, the first chamber 8 and the second chamber 9 are communicated with each other via the PCV valve 10, but if the first chamber 8 and the second chamber 9 are communicated with each other. For example, it is possible to communicate with a simple orifice or communicate with a check valve.

  In the blow-by gas recirculation device of the embodiment, the lubricating oil inlet 18 is disposed on the front side in the vehicle front-rear direction. However, if it is offset in the horizontal direction from the opening 19, for example, It may be arranged on the left or right side in the vehicle left-right direction.

  In the blowby gas recirculation device of the embodiment, the opening 19 is on the upper surface of the head cover 2 between the campus rocket 21a and the cam sprocket 21b which are on the rotational direction side with respect to the vertical direction passing through the rotation center of the campus rocket 21a. The opening 19 is formed on the upper surface of the head cover 2 at a position corresponding to the opposite side of the rotation direction with respect to the vertical direction passing through the rotation center of the campus rocket 21a. The opening 19 may be formed on the upper surface of the head cover 2 at a position corresponding to the rotation direction side with respect to the vertical direction passing through the rotation center of the campus rocket 21b.

  In the blow-by gas recirculation device of the embodiment, the opening 19 is formed on the upper surface of the head cover 2 and at a position corresponding to the upper side of the chain chamber 20. You may form in the position corresponding to the upper direction of a valve mechanism chamber.

  As mentioned above, although embodiment of this invention was described using the Example, this invention is not limited to such an Example, In the range which does not deviate from the summary of this invention, it can implement with a various form. Of course.

It is a schematic block diagram which shows the outline of a structure of the engine as an internal combustion engine provided with a blowby gas recirculation apparatus. It is the back surface lineblock diagram which looked at the head cover from the back surface. It is the route figure which showed the injection | pouring path | route of lubricating oil. It is the arrangement figure which showed the arrangement position in the head cover upper surface of a gas-liquid separation device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Engine 2 Head cover 2c Flange part 2d Boss part 2e Chain chamber cover part 3 Cylinder head 3a Intake port 3b Communication path 4 Baffle plate 5 Blover by-gas flow path 5a, 12a Groove 5b, 12b, 19 Opening part 7 Gas-liquid separation Device 7a Body portion 8 First chamber 8a, 9a, 15a Cavity portion 9 Second chamber 10 PCV valve 12 Blover by-gas recirculation path 12b Opening portion 12c Linear portion 12d Connecting portion 13 Lid member 13a Flange 13b Protruding portion 15 Introducing path 16 Oil filler cap 17 Packing 18 Lubricating oil inlet 20 Chain chamber 21a, 21b Cam sprocket 30 Insertion part 100 Inflow part 120 Upward hole 121 Connection hole 122 Groove part R Rib

Claims (7)

In an internal combustion engine equipped with a blow-by gas recirculation device for recirculating blow-by gas to an intake system,
The blow-by gas reduction device includes:
A blow-by gas flow path through which the blow-by gas provided inside the head cover flows;
A first opening as an inlet provided in a wall surface of the head cover communicating with the blow-by gas flow path;
The blow-by gas is introduced from the first opening and the first chamber in which the oil component in the introduced blow-by gas can be separated; and the first chamber in which the blow-by gas from which the oil component has been separated is introduced is a partition wall A second chamber communicating via the gas-liquid separating means,
A second opening as a lead-out port provided on the wall surface of the head cover for introducing the blow-by gas from the second chamber into the head cover;
A communication path communicating with the intake system formed inside the cylinder head;
A blow-by gas recirculation path provided inside the head cover for supplying the blow-by gas derived from the second opening to the communication path;
An internal combustion engine.   The internal combustion engine according to claim 1, wherein the blow-by gas flow path is formed so as to be capable of separating oil in the blow-by gas. The first opening and the second opening are formed on an upper surface of the head cover,
The internal combustion engine according to claim 1 or 2, wherein the gas-liquid separation means is disposed on an upper surface of the head cover.   The gas-liquid separation means controls a flow rate of the blow-by gas flowing from the first chamber to the second chamber and prevents the blow-by gas from flowing back from the second chamber to the first chamber. The internal combustion engine according to any one of claims 1 to 3, wherein the first chamber and the second chamber are communicated with each other via a valve.   The internal combustion engine according to claim 4, wherein the control valve is formed above the first chamber. The upper surface of the head cover is formed with a third opening into which lubricating oil can be injected through the chain chamber,
The gas-liquid separation means includes lubricating oil injection means in which an injection port for injecting the lubricating oil is formed at a position offset in a horizontal direction with respect to the third opening, and the lubricating oil injected from the injection port The internal combustion engine according to any one of claims 3 to 5, wherein an introduction path for introducing the gas into the third opening is formed.   The internal combustion engine according to claim 6, wherein the gas-liquid separation unit includes the second chamber formed by using a part of the lubricating oil injection unit.

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