JP2002309950A - Exhaust system structure of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain sealability at an inner fitted portion of a seal ring portion to a turbine at a time of extension, corresponding to the extension of an exhaust outlet pipe caused by influence of high temperature exhaust gas, by providing structure in which an inlet end portion of the exhaust outlet pipe of a supercharger is made as the seal ring portion, an exhaust outlet end of the turbine is provided with an annular groove, and the seal ring portion is slidably fitted into the groove. SOLUTION: An internal combustion engine has the structure in which two outlets are formed to an exhaust manifold, and the outlets are respectively connected to the two independent superchargers. In the structure, the superchargers are disposed above the exhaust manifold so that rotating shafts of the supercharger are parallel to a longitudinal direction of the exhaust manifold and exhaust outlets of the superchargers face each other, and the exhaust outlets are connected to an exhaust bend. Exhaust outlets pipes are disposed each between the supercharger and the exhaust bend, and the seal ring portions are disposed at the connecting portions of the exhaust outlets of the superchargers to the exhaust outlet pipes.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an exhaust system structure of an internal combustion engine.

[0002]

2. Description of the Related Art In response to the demand for reduction of exhaust emissions, it is demanded that the supply pressure be made more efficient. At this time, cylinders are divided into two groups and connected independently to an exhaust manifold, or all cylinders are connected to one cylinder. By communicating with the exhaust manifold, two exhaust outlets are formed in the exhaust manifold, and each exhaust outlet is connected to an independent turbocharger.
2. Description of the Related Art An internal combustion engine that supplies air to an air supply pipe that supplies air to multiple cylinders to improve air supply efficiency is known. Among them, the one in which the exhaust outlets of two superchargers are opposed to each other and merged into one exhaust bend to reduce the size is known.

[0003]

In the conventional internal combustion engine, each supercharger has a structure directly attached to the outlet end of the exhaust manifold, and the outlet end of the exhaust manifold itself is attached to the turbocharger. Had to be processed. In the case of the twin turbo type, even if two superchargers are provided, if the exhaust outlets of both superchargers face each other in order to achieve compactness, both superchargers will be mounted in opposite directions. Therefore, the mounting portions of the exhaust manifolds of each group to the supercharger cannot be dealt with unless they have different shapes. That is, the exhaust manifold has a complicated shape, and the shapes of the exhaust manifolds of the two groups cannot be unified, so that there is a problem that the processing cost is increased.

In the present invention, the inlet end portion of the exhaust outlet pipe of the turbocharger is a seal ring portion, and an annular groove is provided at the exhaust outlet end of the turbine, and the seal ring portion is slidable in the groove. The internal fitting corresponds to the extension of the exhaust outlet pipe under the influence of high-temperature exhaust, and the internal fitting portion of the seal ring portion to the turbine is configured to maintain the sealing property even during the extension.

[0005]

The present invention uses the following means to solve the above problems. An internal combustion engine having a structure in which two outlets are formed in an exhaust manifold, and each outlet is connected to two independent superchargers, wherein rotation axes of both superchargers are parallel to a longitudinal direction of the exhaust manifold. In a structure in which both superchargers are arranged above the exhaust manifold with the exhaust outlets of the turbocharger facing each other and both exhaust outlets are connected to one exhaust bend, the supercharger and the exhaust bend The exhaust outlet pipes are provided between them, and a seal ring portion is provided at a joint between the exhaust outlet of each supercharger and each exhaust outlet pipe.

[0006]

Embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 shows a supercharger T1 via a spacer 2
・ Exhaust manifold 1 of internal combustion engine with T2 attached
1 is a partial cross-sectional view of the front of the pipe portion, FIG. 2 is a partial cross-sectional view of the same as the turbocharger T1 mounting portion viewed from the left side in FIG. 1, and FIG. FIG. 4 is a partial cross-sectional front view of the exhaust manifold 1 of an internal combustion engine having a structure provided with a wastegate pipe 9, and FIG. 5 is a structure provided with a wastegate pipe 9 ′. 6 is a partial cross-sectional side view of the exhaust manifold 1 piping portion of the internal combustion engine of FIG. 6, and FIG.
Exhaust manifold 1 of the type to be supplied to the turbocharger T
FIG. 7 is a partial cross-sectional front view of a pipe portion of an exhaust manifold 1 of a sequential control type internal combustion engine in which the engine 2 can be stopped, and FIG. 8 is an exhaust / supply system diagram of the structure shown in FIGS. 6 and 7, and FIG. 9 is an exhaust manifold 1 of a type having a two-part interior and independently supplying exhaust to both superchargers T1 and T2. FIG. 10 is a partial cross-sectional front view of an exhaust manifold 1 piping portion of a sequential control type internal combustion engine in which the turbocharger T2 can be stopped, FIG. 10 is an exhaust / supply system diagram in the structure shown in FIG. Is a partially cut-away plan view showing a water-cooled exhaust manifold 1 'having a welded assembly structure, and FIG. 12 is a partially cut-away plan view showing a water-cooled exhaust manifold 1 "having a welded structure.

First, it is assumed that the internal combustion engine (engine) according to the embodiment shown in FIGS. 1 to 12 is a six-cylinder engine. First, the structure of the exhaust manifold will be described. As shown in FIG. 1 and the like, the exhaust manifold 1 is mounted on the front surface of the cylinder head CH, and is separately mounted on the front surface of the cylinder block CB via support members 8.8. . Note that an air supply connection pipe 6 is provided above the exhaust manifold 1 in parallel with the longitudinal direction of the exhaust manifold 1.
The exhaust manifold 1 is supported by support members 7. Exhaust manifolds 1 'and 1 "to be described later are attached and supported similarly to the exhaust manifold 1 shown in FIG.

In this embodiment, the exhaust manifold shown in FIGS. 1 to 12 is of a water-cooled type, but the exhaust manifold 1 shown in FIGS. 1 to 10 has an integral casting structure, and the exhaust manifold 1 shown in FIGS. “· 1” denotes a welded assembly structure. First, the former water-cooled exhaust manifold 1 having an integral casting structure shown in FIGS. 1 to 10 will be described. The interior of the exhaust main pipe 1b is shown in FIGS. (1b'.1
b ') is covered with an external cover 1a, and a space between the external cover 1a and the exhaust main pipe 1b (1b', 1b ') is used as a cooling water chamber. On the inner surface of the outer cover 1a, a total of six exhaust introduction pipes 1c, 1c,... Are projected so as to communicate with the exhaust passage formed in the cylinder head CH of each cylinder. Exhaust outlets 1d are formed on the upper surface to communicate with the respective superchargers T (later-described spacer 2). Further, cooling water inlets and outlets are provided in the outer cover 1a, and cooling water pipes WP, WP for supplying and discharging the cooling water in the cooling water chamber are formed in the respective openings as shown in FIGS. It is connected to.

As described above, a total of six exhaust introduction pipes 1c, 1c... Extend from the inner surface of the outer cover 1a to the cylinder head CH of each cylinder. 9 has a continuous exhaust main pipe 1b communicating with all the exhaust introduction pipes 1c, 1c.
Some have two exhaust main pipes 1b 'and 1b' communicating with three left and right exhaust introduction pipes 1c and 1c.
Exhaust outlet 1d that discharges exhaust gas to turbochargers T1 and T2 described later
4d is formed on the left and right portions of the upper end of the exhaust main pipe 1b in the former structure shown in FIGS. 4 and 6, while on the upper end of each exhaust main pipe 1b 'and 1b' in the latter structure shown in FIG. It is formed. Accordingly, the former is, as shown in FIG. 8, all cylinders C1 to C6.
And is introduced into the two superchargers T1 and T2. In the latter case, as shown in FIG. 10, the exhaust from the cylinders C1 to C3 and the exhaust from the cylinders C4 to C6 are independent of each other. It is structured to be introduced into the superchargers T1 and T2. In the latter structure shown in FIGS. 9 and 10, both superchargers T
A communication passage (R in FIG. 10) for communicating exhaust gas from each exhaust main pipe 1b 'and 1b' at the inlet of 1.T2 is provided so as to be prepared for operation of only one turbocharger described later. ing.

The exhaust manifold 1 shown in FIGS. 1 to 10 has an outer cover 1a, an exhaust main pipe 1b or 1
The b ′, the exhaust gas introduction pipe 1c, and the exhaust gas outlet 1d are integrally formed from an integrated casting mold.

Next, a description will be given of the water-cooled exhaust manifolds 1 'and 1 "of the welded assembly type structure shown in FIGS. 11 and 12. First, in each case, a supercharger T (a spacer 2 to be described later) is moved from a cylinder head CH. The exhaust passage interposed therebetween is covered with an external cover 18 (18 '), and a cooling water chamber is formed in a space between the two.
8 ′), six exhaust introduction pipes 19 and 19 ′ (four exhaust introduction pipes 19 and two exhaust introduction pipes 19 ′) project from the inner surface of the cylinder head. The exhaust passage in the outer cover 18 of the exhaust manifold 1 ′ shown in FIG. 11 is formed by welding the outer end of the exhaust branch pipe 20 to the inner end of the exhaust introduction pipe 19 and connecting the exhaust branch pipe 20 to the exhaust merge pipe 21. The other end and the inner end of the exhaust introduction pipe 19 'are welded. (The exhaust introduction pipe 19 'is directly welded to the exhaust junction pipe 21 without passing through the exhaust branch pipe 20). The exhaust manifold 1 ′ has three exhaust introduction pipes 19.
The exhaust system has two exhaust merging pipes 21 communicating with 9 ′, and therefore has the exhaust system structure shown in FIG. Is supplied.

Next, the exhaust passage in the outer cover 18 'of the exhaust manifold 1 "shown in FIG. 12 is provided at the inner end of the exhaust introduction pipe 19 among the exhaust introduction pipes 19 and 19' communicating with the respective cylinder heads CH. The outer ends of the exhaust branch pipes 20 'are welded, and the inner ends of the two exhaust branch pipes 20' and the inner ends of the two exhaust introduction pipes 19 'are welded to one exhaust merging pipe 21'. The exhaust manifold 1 ″ has six exhaust introduction pipes 19, 19 ′ connected to one exhaust merging pipe 21 ′.
However, only one outlet flange portion 21'a of the exhaust merge pipe 21 'is formed to supply exhaust gas to one supercharger T. Of course, two outlet flange portions 21'a may be formed in the exhaust merge pipe 21 '. In this case, the exhaust supply structure shown in FIG. 8 is obtained.

In the exhaust manifold 1 '(1 "), the outer cover 18 (18") and each exhaust introduction pipe 19
19 ′, and the outer cover 18 (18 ′),
Spacing 2 formed at the upper end of exhaust merging pipe 21 (21 ')
It is also welded to the outlet flange portion 21a (21'a) for connection to the connector. Watertightness is maintained at each of the above welding locations.

In the following embodiments, the exhaust manifold 1 is not limited to the integral-cast exhaust manifold 1 shown in FIGS. 1 to 10, but also to the welded-assembly exhaust manifold 1 'shown in FIG. Can be replaced by As described above, if two outlet flange portions 21′a are provided, FIG.
The illustrated exhaust manifold 1 ″ is also applicable (the exhaust manifold 1 ″ having a structure having two outlet flange portions 21 ′) is also applicable.
Let it be α. ).

The mounting structure of the supercharger will be described with reference to FIGS. In forming a twin-turbo engine, two superchargers T1 and T2 are employed.
1 · T2 is the same, and the mounting direction is simply reversed in order to make the exhaust outlets face each other.
Each of the turbochargers T1 and T2 has a turbine T and a blower B, respectively.
And the turbine T has its inlet end Ta
The exhaust outlet 1 opened to the left and right of the upper end of the exhaust manifold 1
d. 1d. Exhaust gas introduced from the exhaust manifold 1 is compressed by the turbine T, and surplus exhaust gas is discharged through an exhaust outlet pipe 3 and an exhaust bend 4 interposed between the two exhaust outlet pipes 3. The lower part of the exhaust bend 4 is supported by the support member 5 on the upper surface of the exhaust manifold 1. On the other hand, the blower B introduces exhaust air compressed by the turbine T in addition to introducing air supply from outside through the outside air introduction port Ba, and sends them out as air supply. It is sent to an intercooler (supply air cooler) IC via the connecting pipe 6. Further, air is supplied from the intercooler IC to the cylinder head CH of each cylinder.
Is sent to

The exhaust manifold 1 shown in FIGS. 1 to 3 is of a type having a connected exhaust main pipe 1b inside similarly to the exhaust manifold 1 shown in FIG. 4 (the exhaust manifold 1 ″ α can be applied). Therefore, since the exhaust gas introduced into both the superchargers T1 and T2 communicates in the exhaust manifold 1, the supercharger is formed without forming the communication passage R above the exhaust manifold 1. Machine T1 ・ T
2 is attached. When the exhaust manifold 1 has independent exhaust main pipes 1b 'and 1b',
The point at which the communication passage R is provided is different in the mounting structure of the supercharger. This will be described later in the description of the mounting structure of the exhaust control valve based on FIGS. 9 and 10.

A spacer 2 is provided between the exhaust outlet 1d of the exhaust manifold 1 and the inlet end Ta of the turbine T of the superchargers T1 and T2. The spacer 2 has a tubular structure,
The exhaust manifold 1 also serves as an exhaust communication pipe from the exhaust manifold 1 to the turbines T of the superchargers T1 and T2. The shape is exhaust manifold 1
The vicinity of the lower end serving as a mounting seat to the exhaust manifold 1 is perpendicular to the longitudinal direction of the exhaust manifold 1, and is bent in the shape of a "ku" halfway as shown in FIGS. This is for connecting the extension lines of the rotating shafts of the superchargers T1 and T2 so as to be connected to the exhaust outlet pipes 3 of the superchargers T1 and T2 and share the exhaust bend 4. That is, the exhaust passage in the turbine T has a spiral shape as shown in FIGS. 2 and 3, and the inlet end Ta is unevenly distributed forward or backward when the front and rear are reversed, as in the case of the turbochargers T1 and T2. I do. In the case of this embodiment, that of the supercharger T1 is rearward as shown in FIG.
It is leaning forward as in FIG. Therefore, if the same spacer 2 is reversed, the upper end of the spacer 2 serving as a mounting seat to the inlet end Ta of the turbine T is provided as shown in FIG. It may be leaning toward the rear or leaning forward as shown in FIG. Therefore, in order to make the exhaust outlet of the turbine T face-to-face, the superchargers T1 and T2 which are mounted with the mounting positions reversed in the front-rear direction are arranged on the exhaust manifold 1 only by changing the mounting direction of the same spacer 2. It can be attached.

If a turbocharger having a different structure is used as the turbochargers T1 and T2, the outlet end of the exhaust manifold 1 must be changed in the related art, so that the exhaust manifold itself must be reworked. However, if the structure is attached through the spacers 2 as described above, it can be dealt with by reworking the spacers 2 separate from the exhaust manifold 1, and the cost can be reduced.

Next, a connection structure between the turbine T of each of the turbochargers T1 and T2 and the exhaust outlet end 3 will be described. A seal ring portion 3a is provided at an inlet end of the exhaust outlet pipe 3, and a ring-shaped groove is provided at an exhaust outlet end Tb of the turbine T, and the seal ring portion 3a is slidably fitted in the groove. It has become. That is, the exhaust outlet pipe 3 is slidable with respect to the turbine T, whereby the exhaust outlet pipe 3 responds to the extension of the exhaust outlet pipe 3 under the influence of high-temperature exhaust gas. The inner fitting portion of the seal ring portion 3a maintains the sealing property.

Next, a structure having a waste gate passage shown in FIG. 4 will be described. In this embodiment,
The inside of the exhaust manifold 1 has a structure having a connected exhaust main pipe 1b (the exhaust manifold 1 ″ α is applicable), and both exhaust outlets 1b at the upper end of the exhaust main pipe 1b.
A waste gate introducing opening 1e is provided between the exhaust gates 1b at a position below the exhaust bend 4. In the exhaust bend 4, a waste gate outlet pipe 4a is formed below the junction of the exhaust pipes 4b communicating with the exhaust outlet pipes 3.3 of the superchargers T1 and T2. Then, the waste gate introduction opening 1e and the waste gate outlet pipe 4a.
A wastegate pipe 9 which forms a wastegate passage 9a penetrating in the vertical direction is interposed between the two. By providing the waste gate pipe 9, the support member 5 which supports the exhaust bend 4 with respect to the exhaust manifold 1 becomes unnecessary.

In the waste gate passage 9a,
A waste gate valve 10 is disposed at an opening at the lower end of the exhaust manifold 1 so as to face the waste gate introduction opening 1 e of the exhaust manifold 1. An actuator 11 for driving the wastegate valve 10 is provided outside the wastegate pipe 9. The actuator 1
1 connects the air pipe 11a to an air supply connection pipe 6 (not shown) so as to introduce air in the air supply connection pipe 6, and the drive amount is adjusted by this air pressure. On the other hand, the actuator 11 is connected to the switching arm 10a of the waste gate valve 10, and the actuator 11
The opening amount of the wastegate valve 10 is adjusted based on the driving amount of the wastegate valve 10. For example, when the supply pressure increases, the opening amount of the waste gate valve 10 increases, exhaust gas flows more through the waste gate passage 9a, and the amount of exhaust gas introduced into the superchargers T1 and T2 is reduced. In this way, the amount of exhaust gas introduced into the superchargers T1 and T2 is adjusted based on the supply air pressure, and the supply air pressure can be maintained at the set pressure amount.

In the case of FIG. 4, the wastegate introduction opening 1e is provided at the upper end of the exhaust manifold 1, and the entrance opening of the wastegate outlet pipe 4a of the exhaust bend 4 is provided downward. However, depending on the piping position of the air supply communication pipe 6 that is piped above the exhaust manifold 1, it may be necessary to offset outward. In such a case, as shown in FIG. 5, the waste gate introduction opening 1e 'is opened on the outer surface of the exhaust manifold 1, and the exhaust bend 4' is opened with the inlet opening of the waste gate outlet pipe 4'a. , And a wastegate pipe 9 ′ bent in a U-shape in side view is piped between the wastegate introduction opening 1 e ′ and the entrance opening of the wastegate outlet pipe 4 ′ a. Thus, a space above the exhaust manifold 1 can be secured.

Next, a twin-turbo type engine equipped with superchargers T1 and T2, which is capable of switching between a state in which only one supercharger is operated and a state in which both superchargers are operated. The arrangement structure of the control valve in a system that employs control will be described with reference to FIGS. First, FIGS. 6 to 8 show an embodiment in which the exhaust manifold 1 has a structure in which the inside of the exhaust manifold 1 communicates with exhaust introduction pipes 1c, 1c... It is. (In this regard, the above-described exhaust manifold 1 ″ is applicable.) The turbochargers T1 and T2 are provided with the exhaust manifolds through spacers 2 and 2, respectively, similarly to the structure of FIGS. The exhaust control valve 12 is disposed only in the spacer 2 to which the supercharger T2 is attached, in the two spacers 2. The exhaust control valve 12 has a rotating shaft 12a. The valve 12a is rotatable by pivotally supporting 12a on the side surface of the spacer 2. The amount of valve opening is adjusted at the rotational position. To lower the supply pressure, the exhaust control valve 12 is closed and the supercharger T2
Of the exhaust gas to the turbine T is stopped. In the turbocharger T2 provided with the exhaust control valve 12 at the inlet, when the exhaust control valve 12 is closed and the introduction of exhaust gas is stopped, the exhaust outlet from the blower B to the air supply connection pipe 6 has a low pressure. As a result, the air supplied from the blower B of the supercharger T1 in the operating state flows back to the outlet side of the blower B of the supercharger T2 in the stopped state via the air supply communication pipe 6, and Decrease. In order to prevent this, at the outlet of the turbocharger T1 (the outlet of the blower B) provided with the exhaust control valve 12 at the inlet, an air supply control valve 13 is provided as shown in FIG. The valve is closed in conjunction with the valve closing. Further, at a position upstream of the air supply control valve 13,
An air supply relief valve 14 is provided, and the outside air inlet B of the blower B is provided.
The air supply control valve 13 is opened in conjunction with the closing of the air supply control valve 13.

As described above, the exhaust control valve 12 is not attached to the exhaust manifold 1 itself having a complicated pipe structure, but is attached to the spacer 2, thereby contributing to cost reduction. In addition, it is also possible to easily remove the exhaust control valve 12 from the spacer 2.
The engine can be a normal twin-turbo-type engine as seen in FIG.

Finally, the arrangement of the exhaust control valve of the split twin turbo engine shown in FIGS. 9 and 10 will be described. Also in this case, when only one supercharger is operated, the operation is stopped by the supercharger T2, and the air supply system on the outlet side of the supercharger T2 has the structure shown in FIGS. 6 to 9. Similarly, as shown in FIG. 10, an air supply control valve 13 and an air supply relief valve 14 are provided.

In this embodiment, the exhaust manifold 1 has a structure in which the inside is divided into exhaust main pipes 1b 'and 1b'.
This is because the exhaust gas is introduced into each of the superchargers T1 and T2 independently to generate a pulsation in the exhaust gas introduced into the superchargers T1 and T2, thereby pulsating the air supply and improving the air supply efficiency. It is aimed at improving it. (The exhaust manifold 1 'shown in FIG. 11 is applicable.) However, in this case, when the supercharger T2 is stopped, the exhaust from the cylinders C4 to C5 which should be sent to the supercharger T1 is generated. Since the outlet is lost, a structure for guiding these exhausts to the supercharger T2 is required. Therefore, as described above, the two superchargers T1 and T2
When two superchargers are operated by forming a communication passage R between the inlets of the turbochargers, the exhaust is independently introduced to each supercharger, and the turbocharger is closed. , It is open.

Referring to FIG. 9, the mounting structure of the turbochargers T1 and T2 and the arrangement structure of the exhaust control valve will be specifically described.
Each of the superchargers T1 and T2 has the same structure as that of FIGS.
The exhaust control valve 12 is attached to the spacer 2 which is attached to the spacer 2 and to which the supercharger T2 is attached. In order to form a communication passage R, a communication branch pipe 15 is provided between the lower end of each spacer 2 and each exhaust outlet 1d of the exhaust manifold 1.
And a communication pipe 16 is provided between the two communication branch pipes 15. An exhaust control valve 17 is provided in the communication pipe 16.
It is built inside. Explaining the opening and closing of the exhaust control valves 12 and 17, when the supercharger T2 stops, the exhaust control valve 12 closes and the exhaust control valve 17 opens at the same time, and the exhaust from the cylinders C4 to C6 Through the turbocharger T1. When both the turbochargers T1 and T2 are operated and the exhaust control valve 12 is opened, the exhaust control valve 17 is closed in conjunction therewith, and the exhaust from the cylinders C1 to C3 is discharged to the supercharger T1. The exhaust gas from the cylinders C4 to C6 is independently introduced into the supercharger T2.

The high-temperature exhaust gas flows through the communication pipe 16, and if the distance between the communication branch pipes 15 is constant, but the communication pipe 16 itself is stretched due to high temperature, the communication pipe 1 may be stretched.
6 and the communication branch pipe 15 may be damaged. Therefore, as described above, the connecting portion of the exhaust outlet pipes 3.3 to the exhaust outlet end Tb of the turbine T of each of the superchargers T1 and T2 is formed in a seal ring shape so as to be slidable. Reference numeral 16 has a telescopic pipe 16c interposed between a communication main pipe 16a and a communication valve pipe 16b in which the exhaust control valve 17 is provided.
The telescopic tube 16c is made of, for example, bellows-like heat-resistant rubber,
At both ends, telescopic pipe joints 16d, 16d are arranged so as to be flange-connectable to the communication main pipe 16a and the communication valve pipe 16b. The telescoping tube 16c contracts with the extension of the communication main tube 16a and the communication valve tube 16b due to high heat, so that damage to the communication main tube 16a and the communication valve tube 16b can be avoided.

[0029]

As described above, the present invention has the following advantages. That is, since the exhaust end pipe 3 is configured as in claim 1, the inlet end portion of the exhaust outlet pipe 3 is
In this structure, an annular groove is provided at the exhaust outlet end Tb of the turbine T, and the seal ring portion 3a is slidably fitted in the groove. That is, the exhaust outlet pipe 3 is slidable with respect to the turbine T, whereby the exhaust outlet pipe 3 responds to the extension of the exhaust outlet pipe 3 under the influence of high-temperature exhaust gas. The inner fitting portion of the seal ring portion 3a maintains the sealing property.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional front view of an exhaust manifold 1 piping portion of an internal combustion engine having a structure in which turbochargers T1 and T2 are mounted via spacers 2. FIG.

FIG. 2 is a partial cross-sectional side view of the mounting portion of the turbocharger T1 viewed from the left in FIG.

FIG. 3 is a partial cross-sectional side view of the mounting portion of the supercharger T2 viewed from the left in FIG.

FIG. 4 is a partial front sectional view of an exhaust manifold 1 piping portion of an internal combustion engine having a structure in which a waste gate pipe 9 is provided.

FIG. 5 is a partial cross-sectional side view of an exhaust manifold 1 piping portion of an internal combustion engine having a structure provided with a wastegate pipe 9 ′.

FIG. 6 combines exhaust gases from all cylinders to form a double supercharger T1.
FIG. 2 is a front partial cross-sectional view of a pipe portion of an exhaust manifold 1 of a sequential control type internal combustion engine having an exhaust manifold 1 of a type to be supplied to T2 and capable of stopping a supercharger T2.

FIG. 7 is a partial side sectional view of the mounting portion of the supercharger T2 viewed from the left in FIG. 6;

FIG. 8 is an exhaust / air supply system diagram in the structure shown in FIGS. 6 and 7.

FIG. 9 is a diagram showing the inside of a turbocharger having a two-part structure, and the exhaust of the two superchargers T being independent.
1. Exhaust manifold 1 of the type to supply to T2
FIG. 3 is a front partial cross-sectional view of an exhaust manifold 1 piping portion of a sequential control type internal combustion engine in which a supercharger T2 can be stopped.

FIG. 10 is an exhaust / air supply system diagram in the structure shown in FIG. 9;

FIG. 11 is a partial plan sectional view showing a water-cooled exhaust manifold 1 'having a welded assembly structure.

FIG. 12 is a partial plan sectional view showing a water-cooled exhaust manifold 1 ″ having a welded assembly structure.

[Explanation of symbols]

 T1 ・ T2 Supercharger T Turbine B Blower 1 Exhaust manifold 1a Outer cover 1b ・ 1b ′ Exhaust main pipe 1c Exhaust introduction pipe 1d Exhaust outlet 1e Waste gate introduction opening 2 Spacer 3 Exhaust outlet pipe 4.4 ′ Exhaust bend 4 ′ a Wastegate outlet pipe 6 Air supply connection pipe 9 Wastegate pipe 9a Wastegate passage 10 Wastegate valve 11 Actuator 12 Exhaust control valve 13 Air supply control valve 14 Air supply relief valve 15 Communication branch pipe 16 Communication pipe 16a Communication main pipe 16b Communication valve pipe 16c Telescopic pipe 16d Telescopic pipe joint 17 Exhaust control valve 1 'Exhaust manifold 18 External cover 19/19' Exhaust introduction pipe 20 Exhaust branch pipe 21 Exhaust junction pipe 21a Outlet flange 1 "Exhaust manifold 18 'External cover 20 'Exhaust branch pipe 21' Exhaust junction pipe

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Makoto Yuri 1-32 Chaya-cho, Kita-ku, Osaka City, Osaka Prefecture Inside Yanmar Diesel Co., Ltd. (72) Takashi Saeki 1-32, Chaya-cho, Kita-ku, Osaka, Osaka Within Yanmar Diesel Co., Ltd. (72) Inventor Motoi Haneda 1-32 Chayacho, Kita-ku, Osaka City, Osaka Prefecture F-term within the Yanmar Diesel Co., Ltd. 3G004 AA09 BA00 DA01 EA00 3G005 EA16 EA26 FA32 GB26 JA17

Claims (1)

[Claims] 1. An exhaust manifold having two outlets,
An internal combustion engine having a structure in which each outlet is connected to two independent superchargers, wherein the rotating shafts of the two superchargers are parallel to the longitudinal direction of the exhaust manifold, and the exhaust outlets of the two superchargers face each other. In a structure in which both superchargers are arranged above the exhaust manifold and both exhaust outlets are connected to one exhaust bend, an exhaust outlet pipe is provided between each turbocharger and the exhaust bend, An exhaust system structure for an internal combustion engine, wherein a seal ring portion is provided at a joint between an exhaust outlet of a feeder and each exhaust outlet pipe.