JP3444022B2 - Internal combustion engine with rocker cover integrated with intake manifold - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of an internal combustion engine provided with an intake manifold integrated rocker cover in which an intake manifold is integrally formed with a rocker cover covering an upper surface of a cylinder head.

[0002]

2. Description of the Related Art An intake manifold-integrated rocker cover in which a part or the whole of the intake manifold is integrally formed with a rocker cover that covers the upper surface of a cylinder head of an internal combustion engine has been conventionally known. As an example, FIG.
It shows a main part of an internal combustion engine including an intake manifold-integrated rocker cover described in Japanese Patent No. 6564.

In this example, an intake port 72 and an exhaust port 73 are formed in a cross flow type in a cylinder head 71 mounted and fixed on the upper surface of a cylinder block (not shown). The end portion opens in the same plane as the flange surface 74 at the upper end of the cylinder head 71. The rocker cover 75 attached to the upper surface of the cylinder head 71 includes a cover portion 76 that covers the upper surface opening of the cylinder head 71 to define a valve operating chamber, a plurality of branch portions 77 that serve as an intake manifold, and a collector portion. 78 is formed integrally. The branch section 7
7 is formed along the width direction of the cover portion 76 so as to cross the cylinder head 71 from the intake side to the exhaust side. Branch portion 7 extending to the intake side of the cylinder head 71
One end of 7 is curved downward and is connected to the tip of the intake port 72. Also, the branch section 7
The other end of 7 is connected to the collector portion 78. It should be noted that reference numerals 79 and 80 represent the rotation loci of the cam tips on the intake side and the exhaust side.

Fuel injection valves 81 are attached to the outside of the intake ports 72 rising upward, and each fuel injection valve is provided from a fuel supply passage 83 formed inside the cylinder head 71 along the cylinder row direction. The fuel is supplied to 81, and the surplus fuel is returned via the return fuel passage 82.

[0005]

However, the entire intake port 72 having a so-called high port shape as described above is cast integrally with the cylinder head 71, and the fuel injection valve 81 is attached to the cylinder head 71 and the inside of the cylinder head 71 is provided. In the conventional structure in which the fuel supply passage 83 and the return fuel passage 82 are formed, the heat transferred from the main body portion of the cylinder head 71 to the vicinity of the intake port 72 cannot be blocked, and the inside of the fuel injection valve 81 or the fuel Since the temperature of the fuel in the supply passage 83 rises, vapor lock is likely to occur.

A swirl control valve for variably controlling the swirl in the combustion chamber is provided in the intake port 72, especially in the combustion chamber 8.
When it is arranged in the vicinity of 4, it is very difficult to machine the shaft hole and mount the valve body. Moreover, it is difficult to maintain and replace the swirl control valve.

Further, if the EGR gas supply passage and the blow-by gas passage are further integrated inside the cylinder head 71 in order to reduce the external piping, the cylinder head 71
There is a possibility that the structure will become very complicated and the defective rate will increase.

[0008]

An intake manifold-integrated rocker cover-equipped internal combustion engine according to the present invention is provided with a cylinder head having an intake port opening on one side surface, and is attached to the upper surface of the cylinder head and is provided in each cylinder. A corresponding plurality of branch parts are integrally formed on the upper part, and the tip of the outlet side of each branch part is a rocker cover that opens along the same plane as the joint surface with the cylinder head,
An intake port having a flange surface joined to the side surface of the cylinder head and a flange surface flush with the upper surface of the cylinder head, and fixed to the side surface of the cylinder head and the tip of the branch portion of the rocker cover, respectively. An adapter and an intake port adapter formed inside each of the cylinders corresponding to each cylinder. One end is connected to the intake port end of the cylinder head, and the other end is connected to the branch end of the rocker cover. Is integrally formed with the side port passage and the intake port adapter,
And a fuel injection valve mounting portion provided corresponding to each of the upstream side port passages, and a fuel supply formed inside the intake port adapter so as to supply fuel to each of the plurality of fuel injection valve mounting portions. And a passage.

According to a second aspect of the present invention, the inlet side opening and the outlet side opening of the upstream side port passage are offset in one of the crankshaft axial directions, and the upstream side port passage is crankshaft axial direction. It is characterized in that it is inclined with respect to a plane orthogonal to.

According to the third aspect of the invention, an EGR gas supply passage for returning exhaust gas to the combustion chamber and a blow-by gas passage for introducing blow-by gas into the combustion chamber are formed inside the intake port adapter. In addition, the swirl control valve is arranged in the upstream port passage, and the swirl control valve is located downstream of the respective supply ports of the EGR gas supply passage and the blow-by gas passage. To do.

Further, according to the invention of claim 4, there is provided a swirl control valve in which a cutout portion is provided at one side portion of the valve body in the upstream side port passage, and the cutout portion is provided in the upstream side port passage. Is arranged so as to be biased in a direction in which the offset amount in the crankshaft axial direction from the center of the inlet side opening to the notch becomes large.

[0012]

In the above structure, since the intake port adapter is formed separately from the cylinder head and is assembled through a gasket or the like, the vicinity of the fuel injection valve provided on the intake port adapter side or the fuel supply is provided. Heat transfer to the passage is suppressed. That is, the fuel temperature near the fuel injection valve is kept low.

According to the second aspect of the invention, the swirling flow component along the lateral direction of the cylinder is applied while the intake air flows through the upstream port passage.

According to the third aspect of the invention, the swirl control valve is arranged in the intake port adapter which is separate from the cylinder head. Further, the EGR gas supply passage and the blow-by gas passage are also integrally provided inside the intake port adapter, not in the external pipe.

Further, in the structure of claim 4, since the notch portion of the swirl control valve is provided in the direction of increasing the offset amount, the swirling flow component along the lateral direction of the cylinder is more strongly imparted.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings.

1 and 2 show the essential parts of an internal combustion engine with an intake manifold integrated rocker cover according to the present invention. In the figure, 1 indicates a cylinder head mounted and fixed on the upper surface of a cylinder block (not shown). The cylinder head 1 is integrally cast from, for example, an aluminum alloy, and has an intake port 2 opened and closed by an intake valve (not shown) and an exhaust port 3 opened and closed by an exhaust valve (not shown). , Is formed in a cross-flow format. The intake valve and exhaust valve are each 1
Two cylinders are provided for each cylinder, and correspondingly, the intake port 2 and the exhaust port 3 are each formed to have a bifurcated end. Further, at the center position of each cylinder, a spark plug attachment boss portion 4 with which a spark plug 5 is screwed is formed.

The intake port 2 is, as shown in FIG.
It extends obliquely upward, and its tip opening portion opens to the side surface 1 a of the cylinder head 1. The opening has an oval shape that is elongated along the axial direction of the crankshaft. The side surface 1a of the cylinder head 1 in which the intake port 2 is opened is formed substantially at right angles to the lower surface 1b of the cylinder head 1.

Further, the flange surface 6 at the upper end of the cylinder head 1
Is formed so as to pass through the centers of the intake side camshaft 9 and the exhaust side camshaft 10 and to be parallel to the lower surface 1b of the cylinder head 1. Reference numeral 8 denotes a water jacket formed on each part of the cylinder head 1.

In the upper portion of each cylinder on the upper surface of the cylinder head 1, a pair of left and right camshaft bearings 11 in the form of partition walls are formed along the width direction of the cylinder head 1 (direction orthogonal to the axial direction of the crankshaft). A semicircular bearing surface 11 a that supports the camshafts 9 and 10 is formed on the camshaft bearing portion 11. The pair of camshaft bearings 11 of each cylinder are formed in a substantially straight line with the spark plug mounting boss 4 at the center of the cylinder. The illustrated example is an in-line 4-cylinder internal combustion engine, and as shown in FIG.
5 total camshaft bearings including the engine front end 11
Therefore, the camshafts 9 and 10 are supported.

An intake port adapter 12 cast as a separate member is fixed to the side surface 1a of the cylinder head 1 on the intake port 2 side. This intake port adapter 1
In the case of No. 2, four cylinders are integrated, and two flange surfaces 13 and 14 are formed at an angle of approximately 90 °, and one flange surface 13 is one of the heat insulating sheets 15
It is joined and fixed to the side surface 1a of the cylinder head 1 via. The other flange surface 14 is flush with the flange surface 6 at the upper end of the cylinder head 1 when mounted on the cylinder head 1. In addition, so that there is no step between them,
It is positioned and fixed to each other by a knock pin and a reamer bolt (not shown). The heat insulating sheet 15 is required to have a heat insulating property and a sealing property, and a sheet in which several tens of thin natural carbons are stacked and pressed and integrated, or a relatively thick rubber sheet is used.

Inside the intake port adapter 12, an upstream side port passage 41 corresponding to each cylinder is formed. As shown in FIG. 1, the upstream side port passage 41 includes one flange surface 13 to another flange surface 14
It is formed in a curved shape, and one end 41a opening to the flange surface 13 smoothly continues to the intake port 2 of the cylinder head 1. Further, the other end 41b is opened in the flange surface 14 in a substantially vertical direction.

The position of the opening 41b on the flange surface 14 is determined by the position of the opening 41 on the flange surface 13.
It is offset from a in one of the crankshaft axial directions, specifically, to the rear of the engine. That is, as shown in FIG. 2, if the intake port 2 extends in the direction orthogonal to the axial direction of the crankshaft, it is offset by the dimension Y. In FIG. 2, the point X indicates the opening 41.
The center of b is shown, and the line L shows the line that passes through the center of the cylinder and is orthogonal to the axial direction of the crankshaft. Due to this offset, the upstream port passage 41 is inclined with respect to the plane orthogonal to the crankshaft axial direction. If the intake port 2 connected to the upstream side port passage 41 is formed so as to be inclined with respect to a plane orthogonal to the axial direction of the crankshaft so that both are substantially uniformly inclined in a plan view, intake will be smoother. Comes to flow.

On the other hand, the fuel injection valve mounting portions 42 are formed integrally with the intake port adapter 12 at positions outside the upstream side port passage 41 which is curved upward as described above. The fuel injection valve 7 is attached. A plurality of fuel injection valve mounting portions 42 corresponding to each cylinder
A fuel supply passage 43 is formed inside the intake port adapter 12 along the axial direction of the crankshaft so as to sequentially connect the inner space portions thereof. In addition, the fuel supply passage 43
Along with the return fuel passage 44 for returning excess fuel
Are formed. The fuel injection valve 7 is fixed by the cap member 55.

Further, inside the intake port adapter 12, an EGR gas supply passage 45 and a blow-by gas passage 46 are formed along the axial direction of the crankshaft, respectively via the supply ports 45a and 46a. It communicates with the upstream port passage 41 of the cylinder. A swirl control valve 47 is arranged on the downstream side of the upstream port passage 41, that is, in the vicinity of the opening 41a of the flange surface 13. As shown in FIG. 3, the swirl control valve 47 is provided with a notch 49 on one side of a butterfly valve type valve body 48, and is fixed to a central shaft 50 with a screw 51. The swirl control valve 47 is located downstream of the supply ports 45a and 46a.

The notch 49 is formed in the upper edge of the valve body 48 along the upper wall surface of the upstream port passage 41. Further, the crankshaft axial direction is biased in a direction in which the offset amount from the center X of the inlet side opening 41b of the upstream side port passage 41 to the notch 49 becomes large. That is, they are formed on the right side of FIG. 2, respectively.

The rocker cover 16 attached to the upper surface of the cylinder head 1 covers the opening of the upper surface of the cylinder head 1 and defines the valve operating chamber 18 (see FIG. 1).
7 and a plurality of branch parts 1 constituting the intake manifold
9 and collector part 2 which is also a part of the intake manifold
0 and 0 are formed integrally with each other. For example, the whole is integrally cast using an aluminum alloy or the like.

The cover portion 17 has a shallow box shape having side walls on four sides, and the flange surface 21 at the tip of the side wall.
Is in close contact with the flange surface 6 on the outer circumference of the cylinder head 1 via a liquid gasket (not shown). The flange surface 21 is provided with a liquid gasket holding groove 21a. Then, inside the cover portion 17, a partition-like cam bracket portion 22 is formed integrally along the width direction of the cover portion 17. The cam bracket portions 22 are located at positions corresponding to the camshaft bearing portions 11 on the cylinder head 1 side, respectively, and, like the camshaft bearing portions 11, each have a semicircular bearing surface 22a. That is, as shown in FIG. 1, the intake side camshaft 9 and the exhaust side camshaft 10 are rotatably supported between the cam bracket portion 22 and the camshaft bearing portion 11. A pair of bolt insertion holes 23 are vertically formed in each cam bracket portion 22 along both sides of the cam shafts 9 and 10, and the bolts 27 inserted into the bolt insertion holes 23 in FIG.
As shown in, each cam bracket portion 22 is firmly coupled to the cam shaft bearing portion 11 on the cylinder head 1 side. In addition, as shown in FIG.
Auxiliary bolt insertion holes 24 are formed at a plurality of positions, and the cover portion 17 is also coupled to the cylinder head 1 by bolts (not shown) inserted therein. still,
A distributor mounting portion 33 is provided at a portion corresponding to the rear end of the exhaust side camshaft 10. Further, spark plug insertion holes 26 are formed in the central portion of each cylinder of the cover portion 17 so as to correspond to the spark plug mounting boss portions 4 on the cylinder head 1 side. Also, the cover part 1
An oil filler cap mounting hole 28 is formed on the front end side of 7.

A plurality of branch portions 19 cast integrally with the cover portion 17 are formed so as to cross substantially the width direction of the rocker cover 16 from the intake side to the exhaust side of the cylinder head 1. . As shown in FIG. 1, a part of the lower surface side of the branch portion 19 shares a wall portion of the cover portion 17. This branch section 19
In order to reduce the height of the rocker cover 16, the rocker cover 16 has a flat rectangular or oval cross-sectional shape. Further, the branch portions 19 of the adjacent cylinders are cast in a separated form, and when viewed from the outside, the branch portions 19 are separated from each other.
Recessed groove portions 25 are formed between them.

Intake-side tip 19a of each branch portion 19
Is curved downward by approximately 90 degrees along the side wall of the cover portion 17 and opens on the same flange surface 21 as the lower edge of the cover portion 17. And the tip 1 on the intake side
The openings 9a are connected to the inlet side openings 41b of the upstream port passage 41 on the upper surface of the intake port adapter 12, respectively. The periphery of this connecting portion is sealed by a seal ring 52 arranged in a groove provided on the intake port adapter 12 side.

The collector portion 20 has an elongated passage shape along the front-rear direction of the cover portion 17 (axial direction of the crankshaft), and is formed over substantially the entire length of the cover portion 17. The collector portion 20 is configured in such a manner that the exhaust side wall of the cover portion 17 and the wall portion are partially shared,
The exhaust-side tips 19b of the branch portions 19 are connected to the side surfaces of the collector portion 20, respectively. As shown in FIG. 2, an intake inlet 29 to which a throttle chamber (not shown) is attached is provided at the rear end of the collector 20. Further, the collector section 20 is the rocker cover 1
In order to reduce the height of 6, the cover portion 17 is formed so as to overhang outside the side wall of the cover portion 17. In particular, as shown in FIG. 1, the upper surface of the collector portion 20 having a large passage cross-sectional area and the upper surface of each branch portion 19 are located at substantially the same height. In FIG. 1, 31 is a high tension cable connected to each spark plug 5, and 32 is a rubber boot for closing the spark plug insertion hole 26 of the rocker cover 16.

Here, in the present embodiment, as shown in FIG. 2, the branch portions 19 are linear and parallel to each other in a plan view. The branch portions 19 are arranged so as to pass between the cam bracket portions 22 of the cylinders adjacent to each other. In other words,
The bolt insertion hole 23 and the spark plug insertion hole 26 that pass through the cam bracket portion 22 are formed in the concave groove portion 25 between the branch portions 19.
Each branch portion 19 is formed so as to be exposed at.
In particular, the branch portion 19 is similarly inclined with respect to the plane orthogonal to the crankshaft axial direction so as to follow the inclination of the upstream side port passage 41 described above. That is, each branch portion 19 is obliquely connected to the collector portion 20.

In the configuration of the above embodiment, the portion including the upstream side port passage 41 in which the fuel injection valve 7 is arranged is configured as the intake port adapter 12 separately from the cylinder head 1, and between them. Since the heat insulating sheet 15 is interposed, the heat transfer to the fuel injection valve 7, the fuel supply passage 43, and the return fuel passage 44 is suppressed, and an excessive increase in the fuel temperature and thus vapor lock can be prevented.

In the above embodiment, the intake port adapter 12 is cast from an aluminum alloy or the like. However, if a fiber reinforced resin (for example, nylon 66 with fibers) is used instead, the heat will be further improved. Transmission can be suppressed. This resin material is also advantageous in terms of weighing, and the inner surface of the upstream side port passage 41 can be made very smooth if manufactured by injection molding using a so-called meltable core. In the case of resinification as described above, a metal sleeve may be arranged on the bearing of the shaft 50 of the swirl control valve 47, and an appropriate heat resistant structure may be provided on the portion that comes into contact with the high temperature EGR gas.

Further, since the intake port adapter 12 is formed as a separate member, the swirl control valve 47 and EGR are
The gas supply passage 45, the blow-by gas passage 46, etc. can be easily arranged inside. Therefore, a simple structure with less external piping can be obtained.

Further, the upstream side opening 41b and the downstream side opening 41a of the upstream side port passage 41 are offset in the axial direction of the crankshaft, and accordingly, the branch portion 19 is inclined in the axial direction of the crankshaft. Therefore, before the intake air flows into the combustion chamber, a swirling flow component along the lateral direction of the cylinder is given in advance, and swirl is generated in the cylinder. In addition, the intake port 2 and the upstream port passage 4
Since 1 has a so-called high port shape, a so-called tumble flow in the longitudinal direction of the cylinder is also generated. In particular, when the swirl control valve 47 is closed, the cutout portion 49 of the valve body 48 is formed.
Is provided in the direction in which the offset amount is increased, the swirl is effectively strengthened, and the tumble is also strengthened because the notch portion 49 is located above the upstream side port passage 41. Therefore, it becomes suitable for combustion in a mixture having a low air-fuel ratio. Moreover, since the gas supplied to each cylinder from the EGR gas supply passage 45 and the blow-by gas passage 46 is introduced from the upstream side of the swirl control valve 47 through the notch 49, the partial load having a relatively small intake air amount. Swirl and tumble can be generated even in the range and during deceleration operation.

Further, in the structure of the above embodiment, the cam bracket portion 22 for supporting the cam shafts 9 and 10 is formed integrally with the rocker cover 16, so that the parts are different from those when a separate cam bracket is used. Not only the number of points and the number of assembly steps can be reduced, but also the cam bracket 2
Since the head of the bolt 27 for fixing 2 is located outside the cover portion 17, the height of the cover portion 17 and thus the height of the rocker cover 16 as a whole can be reduced.

The upper side of each cam bracket portion 22 is
Since the groove 25 is opened, the rocker cover 1
When attaching 6 to the cylinder head 1, the bolt 27 for fixing the cam bracket portion 22 can be easily tightened through the concave groove portion 25 between the branch portions 19, and good workability can be secured. Similarly, the upper portion of the spark plug insertion hole 26 is also opened, so that the spark plug 5 can be inserted without any trouble.

Further, in the rocker cover 16 having the above structure, the cover portion 17 is reinforced by the tubular collector portion 20 and the branch portion 19, so that the rigidity thereof is improved and the flat portion between the branch portions 19 is Since it is fixed to the cylinder head 1 by the bolt 27 for fixing the cam bracket portion 22, it is possible to reliably prevent the noise generation due to the film vibration of the cover portion 17 and to improve the oil sealability with the cylinder head 1.

Although the rocker cover 16 is made of a light alloy in the above embodiment, it is of course possible to use it as a resin.

Next, FIG. 4 shows a different embodiment of the present invention. In this embodiment, the cam bracket portion 22 is formed integrally with the rocker cover 16 in the above-described embodiment, but a separate cam bracket 61 is provided. That is, the cover portion 1 of the rocker cover 16
7 has a simple box shape, and a valve chamber 18 inside
The cam bracket 61 is housed therein. The cam bracket 61 is fixed to the camshaft bearing portion 11 on the cylinder head 1 side by a pair of bolts 62, respectively. In the figure, 63 is an intake valve, 64 is an exhaust valve, and 6
Reference numeral 5 denotes respective valve springs, 66 denotes a valve lifter, and the valve lifter 66 is made of synthetic resin.

Further, in this embodiment, the rocker cover 16 is used.
A rubber seal gasket 67 is attached to the peripheral edge of the cover portion 17, and the rubber seal gasket 67 seals between the flange surface 6 of the cylinder head 1. Further, a rubber seal gasket 68 is attached so as to surround the tip 19a of the branch portion 19, and the rubber seal gasket 68 seals between the flange surface 14 of the intake port adapter 12. As shown in FIG. 5, the rubber seal gasket 68 has a structure in which a metal reinforcing plate 69 is arranged inside.

[0043]

As is apparent from the above description, in the intake manifold-integrated rocker cover-equipped internal combustion engine according to the present invention, the portion to which the fuel injection valve is attached is provided separately from the cylinder head as the intake port adapter. Since it is configured, it is possible to prevent the fuel temperature in the fuel injection valve and the fuel supply passage from rising excessively and thus vapor lock. Moreover, the swirl control valve can be easily arranged in the upstream port passage.

According to the second aspect of the invention, the swirl flow component along the lateral direction of the cylinder can be given in advance by the upstream port passage of the intake port adapter.

According to the third aspect of the invention, the EGR gas supply passage and the blow-by gas passage do not need to be external pipes, the configuration can be simplified, and when the swirl control valve is closed, these gases are controlled by the swirl control. Since it goes to the combustion chamber through the valve, swirl can be generated even under operating conditions in which the intake air amount is relatively small.

Further, according to the structure of claim 4, the swirl can be generated more effectively.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a main part of an internal combustion engine according to the present invention.

FIG. 2 is a plan view of a rocker cover in this embodiment.

FIG. 3 is a sectional view of a main part of an intake port adapter.

FIG. 4 is a cross-sectional view of a main part of an internal combustion engine showing a different embodiment.

FIG. 5 is an enlarged cross-sectional view of a main part of this embodiment. .

FIG. 6 is a cross-sectional view showing a conventional example of an internal combustion engine with an intake manifold integrated rocker cover.

[Explanation of symbols]

1 ... Cylinder head 2 ... Intake port 7 ... Fuel injection valve 12 ... Intake port adapter 15 ... Insulating sheet 16 ... Rocker cover 19 ... Branch 20 ... Collector 41 ... Upstream port passage 42 ... Fuel injection valve mounting part 43 ... Fuel supply passage 45 ... EGR gas supply passage 46 ... Blow-by gas passage 47 ... Swirl control valve

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification code FI F02M 35/10 311 F02M 35/10 311Z 53/04 P 35/104 69/00 360C 53/04 69/04 A 69/00 360 35/10 102A 69/04 102P 102R 301P (56) Reference JP 6-167260 (JP, A) JP 5-180091 (JP, A) JP 6-147021 (JP, A) JP Flat 6-248958 (JP, A) Actual Open 4-6564 (JP, U) Actual Open 62-56705 (JP, U) Actual Open 63-92069 (JP, U) Actual Open 63-170568 (JP , U) Actual Kaihei 2-141665 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) F02F 1/24 F02F 1/42 F02F 7/00 F02M 35/10

Claims (4)

(57) [Claims] 1. A cylinder head having an intake port opening on one side surface, and a cylinder head mounted on an upper surface of the cylinder head,
A plurality of branch portions corresponding to each cylinder are integrally formed on the upper portion, and the tip of the outlet side of each branch portion is open along the same plane as the joint surface with the cylinder head; An intake port adapter having a flange surface joined to the side surface of the head and a flange surface flush with the upper surface of the cylinder head, and fixed to the side surface of the cylinder head and the tip of the branch portion of the rocker cover, respectively. An upstream port that is formed inside the intake port adapter for each cylinder and has one end connected to the intake port end of the cylinder head and the other end connected to the branch end of the rocker cover. A passage and an integral part of the intake port adapter, and provided corresponding to each of the upstream port passages. An intake manifold including: a fuel injection valve mounting portion; and a fuel supply passage formed inside the intake port adapter so as to supply fuel to each of the plurality of fuel injection valve mounting portions. Internal combustion engine with body rocker cover. 2. The inlet opening and the outlet opening of the upstream port passage are offset in one of the crankshaft axial directions, and the upstream port passage is inclined with respect to a plane orthogonal to the crankshaft axial direction. The internal combustion engine with an intake manifold-integrated rocker cover according to claim 1, wherein 3. An EG for returning exhaust gas to a combustion chamber
An R gas supply passage and a blow-by gas passage for introducing blow-by gas into the combustion chamber are respectively formed inside the intake port adapter, and a swirl control valve is arranged in the upstream-side port passage, and The intake manifold-integrated rocker cover-equipped internal combustion engine according to claim 1 or 2, wherein the swirl control valve is located downstream of the respective supply ports of the EGR gas supply passage and the blow-by gas passage. 4. A swirl control valve having a notch on one side of the valve body in the upstream side port passage, wherein the notch is the center of the inlet side opening of the upstream side port passage. The intake-manifold-integrated rocker cover-equipped internal combustion engine according to claim 2, wherein the intake manifold and the notch are arranged so as to be offset in a direction in which an offset amount in the axial direction of the crankshaft is large.