JP3846863B2 - Exhaust system structure of internal combustion engine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to an exhaust system structure of an internal combustion engine.
[0002]
[Prior art]
  In response to demands for reduced exhaust emissions in response to demands for reducing exhaust emissions, the cylinders are divided into two groups and connected independently to the exhaust manifold, or all the cylinders are connected to one exhaust manifold. Thus, two exhaust outlets are formed in the exhaust manifold, and each exhaust outlet is connected to an independent turbocharger, and is supplied to an air supply pipe that supplies air to multiple cylinders from both turbochargers. Internal combustion engines that supply air and improve the air supply efficiency are known. Among them, it is publicly known that the exhaust outlets of two superchargers face each other and merge into one exhaust bend to achieve a compact size.
[0003]
[Problems to be solved by the invention]
  In a conventional internal combustion engine, each supercharger has a structure that is directly attached to the outlet end portion of the exhaust manifold, and the outlet end portion of the exhaust manifold itself needs to be processed into a shape that can be attached to the supercharger. In the case of the twin turbo type, even if two turbochargers are provided in the same manner, when the exhaust outlets of both turbochargers face each other for the sake of compactness, both turbochargers are mounted in opposite directions. Accordingly, the attachment portions of the exhaust manifolds of each group to the supercharger cannot be dealt with unless they have different shapes. In other words, the exhaust manifold has a complicated shape and the shape of the exhaust manifolds of both groups cannot be unified.
[0004]
  In the present invention, the inlet end portion of the exhaust outlet pipe of the turbocharger is used as a seal ring portion, and an annular groove is provided at the exhaust outlet end of the turbine, and the seal ring portion is slidably fitted in the groove. Thus, the exhaust outlet pipe is extended under the influence of high-temperature exhaust, and the inner fitting portion of the seal ring portion to the turbine is configured to maintain the sealing performance even during the extension.
[0005]
[Means for Solving the Problems]
  The present invention uses the following means in order to solve the above problems.
  An internal combustion engine having a structure in which two exhaust outlets 1d and 1d are formed in the exhaust manifold 1, and the exhaust outlets 1d and 1d are connected to two independent superchargers T1 and T2, respectively. T2 is disposed in the upper part of the exhaust manifold 1, the rotation shafts of both turbochargers T1 and T2 are disposed in parallel to the longitudinal direction of the exhaust manifold 1, and the exhaust of the turbine T that constitutes both turbochargers T1 and T2 In the structure in which the outlet ends Tb face each other and both the exhaust outlet ends Tb are connected to one exhaust bend 4, each supercharging The exhaust outlet pipe 3 is interposed between the exhaust outlet end Tb of the turbine T constituting the machines T1 and T2 and the exhaust bend 4, and the exhaust outlet pipe 3 is fixed to the exhaust bend 4 side. An annular groove is provided in the exhaust outlet end Tb of the turbine T, and a seal ring portion 3a is formed by fitting a seal ring on the exhaust outlet end Tb side of the exhaust outlet pipe 3, and the seal ring portion 3a is formed in the annular groove. The exhaust outlet pipe 3 has a sealing property with respect to the turbine T and is slidable.Is.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
  Embodiments of the present invention will be described with reference to the accompanying drawings.
  1 is a partial front sectional view of an exhaust manifold 1 piping portion of an internal combustion engine having a structure in which superchargers T1 and T2 are attached via a spacer 2.
  FIG. 2 is a partial cross-sectional side view of the turbocharger T1 mounting portion as viewed from the left in FIG.
  FIG. 3 is a partial cross-sectional side view of the turbocharger T2 mounting portion as viewed from the left in FIG.
  4 is a partial front sectional view of an exhaust manifold 1 piping portion of an internal combustion engine having a structure provided with a waste gate pipe 9.
  FIG. 5 is a partial cross-sectional side view of a piping portion of an exhaust manifold 1 of an internal combustion engine having a structure provided with a waste gate pipe 9 '.
  FIG. 6 shows an exhaust manifold 1 of a sequential control type internal combustion engine that has an exhaust manifold 1 of a type that combines exhaust from all cylinders and supplies it to both turbochargers T1 and T2, and is capable of stopping the turbocharger T2. Front sectional view of the piping part,
  FIG. 7 is a partial cross-sectional side view of the turbocharger T2 mounting portion as seen from the left in FIG.
  FIG. 8 is an exhaust / air supply system diagram in the structure shown in FIGS.
  FIG. 9 shows an internal combustion engine of a sequential control system that has an exhaust manifold 1 that is internally divided into two parts and that supplies exhaust gas to both turbochargers T1 and T2 independently, and that can stop the turbocharger T2. Front sectional view of exhaust manifold 1 piping part,
  FIG. 10 is an exhaust / air supply system diagram in the structure shown in FIG.
  FIG. 11 is a partial cross-sectional plan view showing a water-cooled exhaust manifold 1 ′ having a welded assembly structure,
  FIG. 12 is a partial cross-sectional view of a water-cooled exhaust manifold 1 ″ having a welded assembly structure.
[0007]
  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 attached to the front of the cylinder head CH, and is separately attached to the front of the cylinder block CB via support members 8 and 8. . An air supply connecting pipe 6 is provided above the exhaust manifold 1 in parallel with the longitudinal direction of the exhaust manifold 1 and is supported by support members 7 and 7 with respect to the exhaust manifold 1. Yes. Further, exhaust manifolds 1 'and 1 "described later are also mounted and supported in the same manner as the exhaust manifold 1 in FIG.
[0008]
  Although the exhaust manifold shown in FIGS. 1 to 12 in this embodiment is water-cooled, the exhaust manifold 1 shown in FIGS. 1 to 10 has an integral casting structure, and the exhaust manifolds 1 ′ and 1 shown in FIGS. "" Is a welded assembly structure. First, the water-cooled exhaust manifold 1 having an integral casting structure shown in FIGS. 1 to 10 will be described.
  As shown in FIGS. 4 and 9, the inside of the exhaust main pipe 1b (1b ′ · 1b ′) is covered with an outer cover 1a, and between the outer cover 1a and the exhaust main pipe 1b (1b ′ · 1b ′). The space is a cooling water chamber. In the outer cover 1a, a total of six exhaust introduction pipes 1c, 1c,... Project from the inner side surface so as to communicate with an exhaust passage formed in the cylinder head CH of each cylinder. Exhaust outlets 1d and 1d are formed on the upper surface so as to communicate with each supercharger T (spacer 2 described later). Further, the cooling water pipes WP and WP for supplying and discharging the cooling water in the cooling water chamber as shown in FIG. 1 and FIG. It is linked to.
[0009]
  As described above, a total of six exhaust introduction pipes 1c, 1c,... Are extended from the inner surface of the outer cover 1a to the cylinder head CH of each cylinder, as shown in FIGS. .. Having one continuous exhaust main pipe 1b communicating with all the exhaust introduction pipes 1c, 1c... And two exhausts communicating with the left and right exhaust introduction pipes 1c, 1c, 1c as shown in FIG. Some have main pipes 1b 'and 1b'. Exhaust outlets 1d and 1d through which exhaust flows out to the superchargers T1 and T2, which will be described later, are formed in the left and right portions of the upper end of the exhaust main pipe 1b in the former structure shown in FIGS. In the illustrated structure, the exhaust main pipes 1b 'and 1b' are formed at the upper ends.
  Therefore, as shown in FIG. 8, the former combines exhausts from all the cylinders C1 to C6 and introduces them into both turbochargers T1 and T2, while the latter exhausts from the cylinders C1 to C3 as shown in FIG. The exhaust from the cylinders C4 to C6 is independently introduced into the superchargers T1 and T2. In the latter structure shown in FIG. 9 and FIG. 10, communication passages (R in FIG. 10) for communicating the exhaust from the exhaust main pipes 1 b ′ and 1 b ′ at the inlet portions of both turbochargers T 1 and T 2 are provided. It is provided to prepare for the operation of only one supercharger described later.
[0010]
  In the exhaust manifold 1 shown in FIGS. 1 to 10, the outer cover 1a, the exhaust main pipe 1b or 1b ′, the exhaust introduction pipe 1c, and the exhaust outlet 1d are integrally formed from an integral casting mold. .
[0011]
  Next, the water-cooled exhaust manifolds 1 'and 1 "of the welded assembly type structure shown in FIGS. 11 and 12 will be described.
  First, in either case, the exhaust passage provided between the cylinder head CH and the turbocharger T (spacer 2 described later) is covered with an external cover 18 (18 '), and the cooling water chamber is formed in the space between the two. 6 exhaust introduction pipes 19 and 19 ′ (4 exhaust introduction pipes 19 and 2 exhaust introduction pipes) are formed from the inner side surface of the outer cover 18 (18 ′) to the cylinder head. 19 ') is projected.
  The exhaust passage in the outer cover 18 of the exhaust manifold 1 ′ shown in FIG. 11 welds the outer end of the exhaust branch pipe 20 to the inner end of the exhaust introduction pipe 19, and the exhaust branch pipe 20 with respect to the exhaust junction pipe 21. Are welded to the inner end of the exhaust pipe 19 '. (The exhaust introduction pipe 19 ′ is welded directly to the exhaust junction pipe 21 without going through the exhaust branch pipe 20).
  The exhaust manifold 1 ′ has two exhaust merging pipes 21 communicating with the three exhaust introduction pipes 19, 19, 19 ′. Therefore, the exhaust manifold 1 ′ has the exhaust system structure shown in FIG. The structure is such that the exhaust gas can be independently supplied to each of the superchargers T · T from the exhaust gas merging pipes 21.
[0012]
  Next, the exhaust passage in the outer cover 18 ′ in the exhaust manifold 1 ″ shown in FIG. 12 is an exhaust branch pipe at the inner end of the exhaust introduction pipe 19 in the exhaust introduction pipes 19 and 19 ′ communicating with each cylinder head CH. The outer ends of 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 confluence pipe 21'. ing.
  In the exhaust manifold 1 ″, all six exhaust introduction pipes 19 and 19 ′ are communicated with one exhaust joint pipe 21 ′, but only one outlet flange portion 21′a of the exhaust joint pipe 21 ′ is formed. The exhaust gas is supplied to one supercharger T. Of course, two outlet flange portions 21'a may be formed in the exhaust gas merging pipe 21 '. The exhaust gas supply structure shown in FIG.
[0013]
  Further, in the exhaust manifold 1 ′ (1 ″), between the outer cover 18 (18 ″) and the exhaust introduction pipes 19 and 19 ′, and between the outer cover 18 (18 ′) and the exhaust merging pipe 21 ( 21 ') is also welded to the outlet flange 21a (21'a) for connection to the spacer 2 described later. Watertightness is maintained in each of the above welding locations.
[0014]
  In the following embodiments, the exhaust manifold 1 is replaced not only by the integrally cast exhaust manifold 1 shown in FIGS. 1 to 10 but also by the welding assembly type exhaust manifold 1 ′ shown in FIG. It is done. As described above, if two outlet flange portions 21′a are provided, the exhaust manifold 1 ″ shown in FIG. 12 can also be applied (an exhaust manifold 1 ″ α having a structure having two outlet flange portions 21 ′ is also applicable. And).
[0015]
  The supercharger mounting structure will be described with reference to FIGS.
  In order to form a twin turbo engine, two turbochargers T1 and T2 are used, but both turbochargers T1 and T2 are the same and are installed so that their exhaust outlets face each other. Only the direction was reversed. Each of the turbochargers T1 and T2 is connected to the turbine T and the blower B, and the turbine T communicates the inlet end Ta with the exhaust outlets 1d and 1d opened to the left and right of the upper end of the exhaust manifold 1. Exhaust gas introduced from the exhaust manifold 1 is compressed by the turbine T, and surplus exhaust gas is discharged through the exhaust outlet pipe 3 and an exhaust bend 4 provided between the exhaust outlet pipes 3 and 3.
  The lower part of the exhaust bend 4 is supported by the support member 5 with respect to the upper surface of the exhaust manifold 1. On the other hand, the blower B introduces the exhaust gas compressed by the turbine T in addition to introducing the intake air from the outside via the outside air inlet Ba, and sends these as the intake air. It feeds into the intercooler (supply air cooler) IC through the connecting pipe 6. Further, the supply air is sent from the intercooler IC to the cylinder head CH of each cylinder.
[0016]
  The exhaust manifold 1 shown in FIGS. 1 to 3 is of a type having an exhaust main pipe 1b connected to the inside (the exhaust manifold 1 ″ α is applicable), similarly to the exhaust manifold 1 shown in FIG. Accordingly, the exhaust manifold 1 has a structure in which all the exhaust gas introduced into the superchargers T1 and T2 communicates with each other, so that the supercharger T1 and the turbocharger T1 T2 is attached.
  When the exhaust manifold 1 includes independent exhaust main pipes 1b 'and 1b', the supercharger mounting structure is different in that the communication path R is provided. This will be described later in the description of the exhaust control valve mounting structure based on FIG. 9 and FIG.
[0017]
  A spacer 2 is interposed from the exhaust outlet 1d of the exhaust manifold 1 to the inlet end Ta of the turbine T of the superchargers T1 and T2. The spacer 2 has a pipe structure, and also serves as an exhaust communication pipe from the exhaust manifold 1 to the turbine T of the superchargers T1 and T2. The shape near the lower end of the mounting seat for the exhaust manifold 1 is perpendicular to the longitudinal direction of the exhaust manifold 1, and refracts into a “<” shape in the middle as shown in FIGS. I am letting.
  This is to connect the exhaust outlet pipes 3 and 3 of both the turbochargers T1 and T2 so that the rotation axis extension lines of the respective turbochargers T1 and T2 coincide with each other so as to 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 rearward if the front and rear are reversed as in the superchargers T1 and T2. To do. In the case of the present embodiment, that of the supercharger T1 is rearward as shown in FIG. 2, and that of the supercharger T2 is forward as shown in FIG.
  Accordingly, 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 closer to the rear or closer to the front as shown in FIG. Therefore, the turbochargers T1 and T2 that are mounted with their mounting positions reversed in order to face the exhaust outlets of the turbine T face each other on the exhaust manifold 1 only by changing the mounting direction of the same spacer 2. It can be attached.
[0018]
  In addition, when adopting a turbocharger having a different structure as the turbochargers T1 and T2, conventionally, since the outlet end of the exhaust manifold 1 has to be changed, the exhaust manifold itself has to be reworked. However, if the structure is attached via the spacer 2, it can be dealt with by reworking the spacer 2 separate from the exhaust manifold 1, and the cost can be reduced.
[0019]
  Next, a connection structure between the turbine T and the exhaust outlet end 3 of each of the superchargers T1 and T2 will be described.
  The inlet end portion of the exhaust outlet pipe 3 is a seal ring portion 3a, and an annular groove is provided in the exhaust outlet end Tb of the turbine T, and the seal ring portion 3a is slidably fitted in the groove. It has become. In other words, the exhaust outlet pipe 3 is slidable with respect to the turbine T. This corresponds to the extension of the exhaust outlet pipe 3 due to the influence of high-temperature exhaust, and even when the exhaust outlet pipe 3 is extended to the turbine T. The inner fitting portion of the seal ring portion 3a maintains the sealing property.
[0020]
  Next, a structure having the 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 continuous exhaust main pipe 1b (the exhaust manifold 1 ″ α can be applied), and both exhaust outlets 1b at the upper end of the exhaust main pipe 1b. A waste gate introduction opening 1e is provided between 1b and below the exhaust bend 4. The exhaust bend 4 communicates with the exhaust outlet pipes 3 and 3 of the superchargers T1 and T2. A waste gate outlet pipe portion 4a is formed below the junction of the exhaust pipe portions 4b and 4b, and a vertical penetrating shape is provided between the waste gate introduction opening 1e and the waste gate outlet pipe portion 4a. A waste gate pipe 9 forming a waste gate passage 9a is provided on the exhaust manifold 4. The waste gate pipe 9 makes it possible to support the exhaust bend 4 with respect to the exhaust manifold 1. Support member 5 is not required.
[0021]
  In the waste gate passage 9a, a waste gate valve 10 is disposed so as to face the waste gate introduction opening 1e of the exhaust manifold 1 at the opening at the lower end thereof. An actuator 11 for driving the wastegate valve 10 is disposed outside the wastegate pipe 9. The actuator 11 has an air pipe 11a connected to an air supply connection pipe 6 (not shown) and introduces air supply in the air supply communication pipe 6, and the drive amount is adjusted by this air pressure. The
  On the other hand, the actuator 11 is connected to the switching arm 10 a of the waste gate valve 10, and the valve opening amount of the waste gate valve 10 is adjusted based on the drive amount of the actuator 11. For example, if the supply air pressure increases, the opening amount of the waste gate valve 10 increases, and a large amount of exhaust gas flows through the waste gate passage 9a to reduce the exhaust gas introduction amount to the superchargers T1 and T2. Thus, the amount of exhaust 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.
[0022]
  In the case of FIG. 4, the waste gate introduction opening 1 e is disposed at the upper end of the exhaust manifold 1, and the inlet opening of the waste gate outlet pipe 4 a of the exhaust bend 4 is disposed downward. Depending on the piping position of the air supply communication pipe 6 piped above the manifold 1, it may be necessary to offset the outside.
  In such a case, as shown in FIG. 5, the waste gate introduction opening 1 e ′ is opened on the outer surface of the exhaust manifold 1, and the inlet opening of the exhaust bend 4 ′ waste gate outlet pipe 4 ′ a is outside. A waste gate pipe 9 'bent toward the U shape in side view is piped between the waste gate introduction opening 1e' and the inlet opening of the waste gate outlet pipe 4'a. The space above the exhaust manifold 1 can be secured.
[0023]
  Next, a twin turbo engine equipped with turbochargers T1 and T2 adopts sequential control that allows switching between a state where only one turbocharger is operated and a state where both turbochargers are operated. The arrangement structure of the control valve in what is to be described will be described with reference to FIGS.
  First, FIGS. 6 to 8 show an embodiment in which the inside of the exhaust manifold 1 communicates with exhaust introduction pipes 1c, 1c... (6 in total) to all cylinders, that is, an exhaust main pipe 1b. It is. (For this, the exhaust manifold 1 ″ can be applied.) The turbochargers T1 and T2 are connected to the exhaust manifold via the spacers 2 and 2, respectively, in the same manner as the structure shown in FIGS. The exhaust control valve 12 is disposed only in the spacer 2 to which the turbocharger T2 is attached, in both the spacers 2 and 2. The exhaust control valve 12 has a rotating shaft 12a.・ It is possible to turn by pivotally supporting 12a on the side surface of the spacer 2. The valve opening amount is adjusted at the turning position, and only the supercharger T1 is operated at low load. When it is desired to lower the supply air pressure, the exhaust control valve 12 is closed and the introduction of exhaust gas into the turbine T of the supercharger T2 is stopped.
  In the supercharger T2 provided with the exhaust control valve 12 at the inlet portion, 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. Therefore, 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, Decreases. In order to prevent this, an air supply control valve 13 is provided at the outlet of the supercharger T1 provided with the exhaust control valve 12 at the inlet (the outlet of the blower B) as shown in FIG. It is structured to close in conjunction with closing. In addition, an air supply relief valve 14 is provided at a position upstream of the air supply control valve 13 so as to return to the outside air inlet Ba side of the blower B, and the valve is opened in conjunction with closing of the air supply control valve 13. It has a structure to do.
[0024]
  Thus, the exhaust control valve 12 contributes to cost reduction by being attached to the spacer 2 instead of being attached to the exhaust manifold 1 itself having a complicated pipe structure. The exhaust control valve 12 can be easily removed from the spacer 2, and when it is removed, a normal twin turbo engine as shown in FIGS. 1 to 3 can be obtained.
[0025]
  Finally, the arrangement structure 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 structure shown in FIGS. 6 to 9 is used in the air supply system on the outlet side of the supercharger T2. Similarly to FIG. 10, an air supply control valve 13 and an air supply relief valve 14 are provided as shown in FIG.
[0026]
  In this embodiment, the exhaust manifold 1 has a structure in which the interior is divided into exhaust main pipes 1b 'and 1b'. This is because the exhaust gas is introduced independently into each of the superchargers T1 and T2, thereby causing pulsation in the exhaust gas introduced into the superchargers T1 and T2, thereby pulsating the supply air and improving the supply efficiency. It aims to improve. (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 that should be sent to the supercharger T1 loses its outlet, so that these exhausts are supplied to the supercharger T2. A structure that leads to is required.
  Therefore, as described above, when the communication path R is formed between the inlet portions of both the turbochargers T1 and T2 and the two turbochargers are operated, exhaust is introduced into each of the turbochargers independently. Therefore, it is configured to be closed and open when only one unit is operated.
[0027]
  From FIG. 9, the mounting structure of each of the superchargers T1 and T2 and the arrangement structure of the exhaust control valve will be specifically described.
  Each of the superchargers T1 and T2 is attached to the spacer 2 similarly to the structure of FIGS. 6 to 8, and an exhaust control valve 12 is attached in the spacer 2 to which the supercharger T2 is attached. Then, in order to form a communication path R, a communication branch pipe 15 is provided between the lower end of each spacer 2 and each exhaust outlet 1 d of the exhaust manifold 1. A tube 16 is interposed.
  An exhaust control valve 17 is provided in the communication pipe 16. The opening and closing of the exhaust control valves 12 and 17 will be described. When the supercharger T2 is stopped, the exhaust control valve 12 is closed, and at the same time, the exhaust control valve 17 is opened, and the exhaust from the cylinders C4 to C6 is connected to the communication pipe 16. 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 with this, and the exhaust from the cylinders C1 to C3 is sent to the supercharger T1. Exhaust gas from the cylinders C4 to C6 is independently introduced into the supercharger T2.
[0028]
  If high-temperature exhaust gas flows in the communication pipe 16 and the distance between the communication branch pipes 15 and 15 is constant, if the communication pipe 16 itself is stretched due to a high temperature, the communication pipe 16 or the communication branch pipe is used. It can also lead to 15 damage. Therefore, as described above, the connecting portion of the exhaust outlet pipes 3 and 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, and the communicating pipe is made slidable. 16, an expansion tube 16c is interposed between the communication main tube 16a and the communication valve tube 16b in which the exhaust control valve 17 is provided. The expansion tube 16c is made of, for example, a bellows-like heat-resistant rubber, and the expansion tube joints 16d and 16d are provided at both ends thereof so that the expansion tube 16c can be connected to the communication main tube 16a and the communication valve tube 16b with a flange. The expansion and contraction pipe 16c contracts as the communication main pipe 16a and the communication valve pipe 16b are stretched due to high heat, and damage to the communication main pipe 16a and the communication valve pipe 16b can be avoided.
[0029]
【The invention's effect】
  Since the present invention is configured as described above, the following effects can be obtained.
  An internal combustion engine having a structure in which two exhaust outlets 1d and 1d are formed in the exhaust manifold 1, and the exhaust outlets 1d and 1d are connected to two independent superchargers T1 and T2, respectively. T2 is disposed in the upper part of the exhaust manifold 1, the rotation shafts of both turbochargers T1 and T2 are disposed in parallel to the longitudinal direction of the exhaust manifold 1, and the exhaust of the turbine T that constitutes both turbochargers T1 and T2 In a structure in which the outlet ends Tb face each other and both the exhaust outlet ends Tb are connected to one exhaust bend 4, the exhaust outlet end Tb of the turbine T constituting each of the superchargers T 1 and T 2 is disposed between the exhaust bend 4. The exhaust outlet pipe 3 is interposed, the exhaust outlet pipe 3 is fixed to the exhaust bend 4 side, an annular groove is provided in the exhaust outlet end Tb of the turbine T, and the exhaust outlet end of the exhaust outlet pipe 3 is provided. Seal ring part 3a fitted with a seal ring on the Tb side The seal ring portion 3a is slidably fitted in the annular groove, and the exhaust outlet pipe 3 is slidable while maintaining sealing performance with respect to the turbine T. Corresponding to the extension of the exhaust outlet pipe under the influence of high-temperature exhaust, the inner fitting part of the seal ring part to the turbine can be configured to maintain the sealing performance even at the time of extension.
  In other words, the exhaust outlet pipe 3 is slidable with respect to the turbine T. This corresponds to the extension of the exhaust outlet pipe 3 due to the influence of high-temperature exhaust, and even when the exhaust outlet pipe 3 is extended to the turbine T. The inner fitting portion of the seal ring portion 3a maintains the sealing property.
[Brief description of the drawings]
1 is a partial front sectional view of an exhaust manifold 1 piping portion of an internal combustion engine having a structure in which superchargers T1 and T2 are attached via a spacer 2. FIG.
2 is a partial cross-sectional side view of a turbocharger T1 mounting portion as seen from the left in FIG.
3 is a partial cross-sectional side view of the turbocharger T2 mounting portion as seen from the left in FIG.
4 is a partial front sectional view of an exhaust manifold 1 piping portion of an internal combustion engine having a structure provided with a waste gate pipe 9. FIG.
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 waste gate pipe 9 '.
FIG. 6 shows an exhaust manifold of a sequential control type internal combustion engine having an exhaust manifold 1 of a type that joins exhaust from all cylinders and supplies it to both turbochargers T1 and T2, and is capable of stopping the turbocharger T2. It is a front fragmentary sectional view of 1 piping part.
7 is a partial cross-sectional side view of the turbocharger T2 mounting portion as seen from the left in FIG. 6;
8 is an exhaust / air supply system diagram in the structure shown in FIGS. 6 and 7. FIG.
FIG. 9 is a sequential control type internal combustion engine having an exhaust manifold 1 of the type in which the inside is divided into two and supplies exhaust gas to both superchargers T1 and T2 independently, and the supercharger T2 can be stopped. It is a partial front sectional view of the exhaust manifold 1 piping part.
10 is an exhaust / air supply system diagram in the structure shown in FIG. 9; FIG.
FIG. 11 is a partial cross-sectional plan 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 turbocharger
  T turbine
  B Blower
  1 Exhaust manifold
  1a External cover
  1b and 1b 'exhaust main pipe
  1c Exhaust pipe
  1d Exhaust outlet
  1e Wastegate introduction opening
  2 spacer
  3 Exhaust outlet pipe
  4.4 'exhaust bend
  4a ・ 4’a Wastegate outlet pipe
  6 Air supply connection pipe
  9 Wastegate tube
  9a Wastegate passage
  10 Wastegate valve
  11 Actuator
  12 Exhaust control valve
  13 Air supply control valve
  14 Air supply relief valve
  15 Branch pipe for communication
  16 communication pipe
  16a Main communication
  16b Communication valve pipe
  16c telescopic tube
  16d expansion joint
  17 Exhaust control valve
  1 'exhaust manifold
  18 External cover
  19.19 'Exhaust pipe
  20 Exhaust branch pipe
  21 Exhaust junction pipe
  21a Outlet flange
  1 ”exhaust manifold
  18 ’outer cover
  20 'exhaust branch pipe
  21 'exhaust merging pipe

Claims (1)

An internal combustion engine having a structure in which two exhaust outlets 1d and 1d are formed in the exhaust manifold 1, and the exhaust outlets 1d and 1d are connected to two independent superchargers T1 and T2, respectively. T2 is disposed in the upper part of the exhaust manifold 1, the rotation shafts of both turbochargers T1 and T2 are disposed in parallel to the longitudinal direction of the exhaust manifold 1, and the exhaust of the turbine T that constitutes both turbochargers T1 and T2 In a structure in which the outlet ends Tb face each other and both the exhaust outlet ends Tb are connected to one exhaust bend 4, the exhaust outlet end Tb of the turbine T constituting each of the superchargers T 1 and T 2 is disposed between the exhaust bend 4. The exhaust outlet pipe 3 is interposed, the exhaust outlet pipe 3 is fixed to the exhaust bend 4 side, an annular groove is provided in the exhaust outlet end Tb of the turbine T, and the exhaust outlet end of the exhaust outlet pipe 3 is provided. Seal ring part 3a fitted with a seal ring on the Tb side Form, the seal ring portion 3a is slidably fitted in the annular groove, the exhaust outlet pipe 3, that the holding sealing against the turbine T, and were slidable An exhaust system structure of an internal combustion engine characterized by the above.

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