JPH07279680A - Variable capacity-type turbocharger - Google Patents

Abstract

PURPOSE:To enable also exhaust gas having the low flow rate to be effectively driven by guiding exhaust gas from an exhaust manifold connected to a cylinder wherein the ignition order does not continue, of a multi-cylinder internal combustion engine into a turbine wheel through an individual guiding passage composed of a plurality of vane members. CONSTITUTION:When a set mode is in the low flow rate range, first and second vane members 24, 25 remains in the closed position, and exhaust gas having the low flow rate from an engine is introduced into first and second introducing parts 21, 22. The exhaust gas introduced into the first exhaust gas introducing part 21 is allowed to flow into a passage 34 through first and third guide passages 30, 32, and the exhaust gas introduced into the second exhaust gas introducing part 22 is supplied to a turbine wheel 20 through respective second and fourth guide passages 31, 33, thereby interference of exhaust gas is prevented. Moreover, when a set mode is in the large flow rate range, respective movable vanes 24, 25 are opened and moved counterclockwise by an actuator, thereby the communication of the second and fourth guide passages 31, 33% is released.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a variable capacity turbocharger which operates a variable blade provided at a peripheral portion of a turbine wheel to change a turbine capacity.

[0002]

2. Description of the Related Art As a means for increasing the output of an internal combustion engine, a turbocharger that applies exhaust gas to a turbine wheel and rotates a compressor provided coaxially with the same blade to improve intake efficiency is effective. It is already installed in various internal combustion engines. The characteristics of the turbocharger are that the exhaust gas is applied to the turbine wheel and the compressor wheel located on the intake side is rotated at high speed to compress the intake air and introduce it into the cylinder. The output tends to be high. Due to such characteristics, the combustion chamber temperature at the time of high rotation tends to rise excessively, and since the compression ratio is usually set to a low value in advance, the output tends to decrease at the time of low rotation. Therefore, a movable vane is placed on the exhaust passage that is formed between the turbine wheel and the turbine housing, and a turbocharger that changes the flow rate of exhaust gas that hits the turbine and cylinders that do not have consecutive ignition sequences are used. A turbocharger has been proposed in which one exhaust manifold is combined, the exhaust passage is separated into a plurality of passages so as to communicate with each exhaust manifold, and exhaust pulsation is used to efficiently apply exhaust gas to a turbine blade.

For example, in a turbocharger having a variable vane described in Japanese Patent Application Laid-Open No. 1-16314, when the flow rate of exhaust gas from the engine is small, the interval (nozzle opening) between the variable vane and the housing is narrowed. By increasing the flow rate of exhaust gas and efficiently rotating the turpin blades with a small flow rate of exhaust gas, the pickup at low speed is improved. Further, in the turbocharger in which the exhaust passage in the housing is isolated corresponding to the exhaust manifold provided for each cylinder whose ignition order is not continuous,
Since the exhaust gas discharged from each manifold is guided to the turbine wheel through different exhaust passages,
Exhaust interference is avoided in the turbine housing, and exhaust gas is efficiently introduced to rotate the turbine wheel.

[0004]

In a turbocharger having a variable vane, the size of the exhaust passage and the opening area of the nozzle portion can be easily narrowed down by adjusting the distance between the variable vane and the housing. It is possible to increase the flow velocity of the exhaust gas flowing, it is possible to rotate the turbine wheel efficiently even when the flow rate of exhaust gas is low, and it is excellent in that the effective area of turbocharge can be widened to the low rotation side. Since the exhaust passage in the housing is not isolated, there is a problem that exhaust pulsation cannot be used. On the other hand, in the turbocharger in which the exhaust passage in the housing is isolated corresponding to the exhaust manifolds provided for each cylinder whose ignition order is not continuous, the exhaust gas from each exhaust manifold is introduced into the individual passages. Although it is excellent in that exhaust pulsation can be used without exhaust interference, since the exhaust passage is partitioned by a fixed partition wall, it is not possible to easily change the passage throttle and widen the effective range of turbo charge. However, it has a problem that it is difficult. An object of the present invention is to provide a variable capacity turbocharger capable of preventing exhaust interference in a variable capacity turbocharger, efficiently introducing exhaust gas into a turbine over a wide range, and rotating a turbine wheel. Especially.

[0005]

Therefore, according to the first aspect of the present invention, the first and second exhaust gases are formed in the collecting portion of the exhaust manifold provided for each cylinder whose ignition sequence is not continuous in the multi-cylinder internal combustion engine. The housing has a first and a second exhaust gas introduction section partitioned by a partition wall that communicates with the outlet, respectively, and a housing that houses the turbine wheel, and is curved so as to follow the turbine wheel, and has a downstream end portion that is connected to the housing. Fixed to a first rotation shaft movably supported,
While being curved along the two first vane members forming the first and second guide passages respectively communicating with the first and second exhaust gas introducing portions, the turbine wheel and the first vane member, Two downstream end portions are fixed to a second rotating shaft rotatably supported by the housing to form third and fourth guide passages that communicate with the first and second guide passages, respectively. Two vane members and control means for switching the rotational positions of the first vane member and the second vane member are provided. The invention according to claims 2 and 3 is characterized in that the control means switches the rotational positions of the first vane member and the second vane member according to the rotational speed of the internal combustion engine and the exhaust gas flow rate of exhaust gas. . According to a fourth aspect of the present invention, the first and second rotating shafts are rotated by a single driving member and switched.
The invention described above is characterized in that the control means switches the rotational positions of the first and second vane members in three stages. According to a sixth aspect of the invention, the first and second partitions are formed by partition walls that respectively communicate with the first and second exhaust outlets formed in the collecting portion of the exhaust manifold of the cylinders whose ignition order is not continuous in the multi-cylinder internal combustion engine. A housing that has an exhaust gas introduction portion and that houses a turbine wheel, a first rotation shaft that is rotatably supported by the housing, is curved so as to follow the turbine wheel, and has a downstream end portion that is A first guide portion having a plurality of first vanes fixed to one rotation shaft, and a plurality of first passages which are partitioned by the first guide portion and communicate with the plurality of exhaust gas introduction portions, respectively. The first passage means, the second rotation shaft rotatably supported by the housing, the turbine wheel and the first vane, and the downstream end of the second rotation shaft. Second passage means which is composed of a second guide portion having a plurality of second vanes fixed to each other and which forms a plurality of second passages which are partitioned by the second guide portion and communicate with the plurality of first passages, respectively. And the first
And a control means for switching the rotational positions of the passage means and the second passage means.

[0006]

According to the first aspect of the present invention, when the multi-cylinder internal combustion engine is in the operating state, the first and second exhaust outlets are formed at the collecting portion of the exhaust manifolds provided for each cylinder whose ignition order is not continuous. Exhaust gas is introduced into the housing from the first and second exhaust introduction portions that are in communication and are partitioned by the partition wall. The introduced exhaust gas is curved along the turbine wheel, and its downstream end is fixed to the first rotating shaft.
The first and second guide passages formed by the first vane member are connected to the first and second guide passages formed by the two second vane members fixed to the second rotating shaft. It is guided to the turbine wheel through the third and fourth guide passages. The rotation positions of the first vane member and the second vane member can be switched by the control means. According to the second and third aspects of the invention, the rotational positions of the first vane member and the second vane member are switched according to the number of revolutions of the internal combustion engine and the exhaust gas flow rate of the exhaust gas. The size of the flow path of the exhaust gas flowing in the third and fourth guide number paths is changed depending on the rotation speed of the internal combustion engine and the exhaust gas flow rate. In the invention according to claim 4, since the first and second rotating shafts are rotated and switched by a single drive member, the number of parts can be reduced as compared with the case where separate drive members are provided, which contributes to space saving. . In the invention according to claim 5, since the control means switches the rotational positions of the first and second vane members in three stages, the first and second guide passages formed by the first and second vane members are formed. The flow rate of the exhaust gas flowing in the third and fourth guide passages is controlled in three stages. According to the sixth aspect of the present invention, when the multi-cylinder internal combustion engine is in the operating state, it is partitioned by the partition walls that respectively communicate with the first and second exhaust outlets formed in the collecting portion of the exhaust manifolds of the cylinders whose ignition orders are not continuous. Exhaust gas is introduced into the housing from the first and second exhaust introduction portions. The introduced exhaust gas is curved along the turbine wheel and has a plurality of first rotary shafts whose downstream end is fixed to the first rotary shaft.
A first guide means having a vane, and a first passage means that forms a plurality of first passages that are partitioned by the first guide portion and communicate with a plurality of exhaust gas introduction portions, and are fixed to a second rotating shaft. A second guide portion having a plurality of second vanes formed therein, and a second passage means that forms a plurality of second passages that are partitioned by the second guide portion and communicate with the plurality of first passages, respectively. , Will be guided to the turbine wheel. The rotation positions of the first passage means and the second passage means can be switched by the control means.

[0007]

1 and 2, reference numeral 1 is an in-line 4-cylinder 4
1 shows a cycle engine (hereinafter referred to as "engine"), in which a variable capacity turbocharger 13 is mounted. The engine 1 accommodates a plurality of cylinders 2 in its main body, and ignition is performed in the order of # 1, # 3, # 4, and # 2 cylinders. An intake port 5 and an exhaust port 6 are formed in the combustion chamber 7 of each cylinder 2 so that they can communicate with each other via intake and exhaust valves 3 and 4. The intake port 5 of each cylinder communicates with an intake passage 9 via an intake manifold 8. The exhaust ports 6 of the # 1 and # 4 cylinders are connected to the exhaust manifold 10A, and the exhaust ports 6 of the # 2 and # 3 cylinders are connected to the exhaust passage 11 via the exhaust manifold 10B.
Is in communication with.

The intake passage 9 is composed of an intake pipe 12 extending from the compressor 14 portion of the turbocharger 13 to the intake manifold 8 via the intercooler 19, and an air cleaner 15 arranged at the tip of the intake pipe 12. The exhaust passage 11 includes a turbine portion 17 of a turbocharger 13 directly connected to the exhaust manifolds 10A and 10B, an exhaust pipe 16 extending from the turbine portion 17, and a muffler 18 provided at a rear end of the exhaust pipe 16. It The intercooler 19 has a well-known configuration in which pressurized air from the compressor 14 portion of the turbocharger 13 is air-cooled and sent to the intake port side.

As shown in FIG. 2, the turbocharger 13 comprises a turbine section 17 for introducing exhaust gas and a compressor section 14 for compressing intake air. The compressor section 14 is provided coaxially with the turbine wheel 20, and a compressor blade (not shown) that compresses intake air and supplies it to the intake manifold 8 is provided in its casing.

As shown in FIGS. 1 and 3, the turbine section 17 rotatably supports and accommodates the turbine wheel 20 and also collects the exhaust manifolds 10A and 10B.
A housing 23 having a first exhaust gas introducing portion 21 and a second exhaust gas introducing portion 22 for introducing exhaust gas from the
A first vane member 24 and a second vane member 2 which are rotatably supported by 3 and are arranged along the turbine wheel 20.
5, a control unit 27 as a control unit including a drive unit 26 that operates the first vane member 24 and the second vane member 25 to change the turbine capacity.

In the housing 23, the first exhaust gas introducing portion 2 is provided.
A scroll-shaped exhaust passage 34 having the first and second exhaust introduction portions 22 as inlets is formed between the turbine wheel 20 and the inner peripheral surface 23b of the housing. First exhaust introduction part 2
The first and second exhaust gas introducing portions 22 are provided in the vicinity of the joint flange portion 23a of the housing 23 with the collecting portion 10C.
The flow path 34 is formed by being partitioned by a partition wall 10D that is integrally molded to 0C and extends into the housing 23.
The inside of the collecting portion 10C is divided by a partition wall 10D into an exhaust outlet 10E of the exhaust manifold 10A and an exhaust outlet 10F of the exhaust manifold 10B. The first exhaust gas introducing portion 21 and the second exhaust gas introducing portion 22 are connected to the exhaust gas outlet 10E,
It communicates with 10F respectively. Also, the housing 2
As shown in FIG. 3, 3 is formed so that the flow passage opening area A of the first exhaust gas introducing portion 21 and the second exhaust gas introducing portion 22 is maximized.

The first vane member 24 is composed of two thin vanes 24A and 24B made of heat-resistant metal, and is arranged on the flow path 34 located on the exhaust upstream side of the second vane member 25. The vanes 24A and 24B are curved so as to extend along the turbine wheel 20, respectively, and the downstream end portions 24Aa and 24Ba thereof are spaced apart from the first rotation shaft 28 rotatably supported by the housing 23. Each is fixed. The second vane member 25 is also the first vane member 24.
Similarly, it is composed of two thin vanes 25A and 25B made of heat-resistant metal, and is curved along the vanes 24A and 24B, respectively, and along the outer periphery of the turbine wheel 20. Downstream end portions 25Aa, 25 of the vanes 25A, 25B
Ba is fixed to the second rotating shaft 29 rotatably supported by the housing 23 with a space. That is, the first vane member 24 and the second vane member 25 have the flow passage 34.
A first guide passage 30 communicating with the first exhaust introduction portion 21 is disposed between the vane 24a and the inner peripheral surface 23b of the housing and is disposed so as to form an exhaust passage having a continuous scroll curve above. A second guide passage 31 communicating with the second exhaust gas introducing portion 22 is formed between 24A and 24B, and the inner peripheral surface 2
A third guide passage 32 communicating with the first guide passage 30 is formed between 3b and the vane 25A, and a fourth guide passage 33 communicating with the second guide passage 30 is formed between the vane 25A and the vane 25B. There is. In addition, the third guide passage 32 and the fourth
The opening areas of the opening nozzles B and C located at the lower end of the guide passage 33 are the same as those of the first vane 24 and the second vane 25 shown in FIG.
It is set to be smaller than the opening area A in the closed position shown in.

The first rotating shaft 28 and the second rotating shaft 29 extend to the outside of the housing 23 and are integrally connected to the outer levers 26a and 26b constituting the driving means 26. The free ends of the outer levers 26a and 26b are linked to a movable rod 26d of an electromagnetic actuator 26c that constitutes the driving means 26. An electromagnetic solenoid is used as the electromagnetic actuator 26c here. The electromagnetic actuator 26c is placed under the control of the control unit 27, and the first vane 24 and the second vane 25 are guided to the first guide shown in FIG. The passage 30 and the third guide passage 32, and the second guide passage 31 and the fourth guide passage 33 are placed in the closed position where they are in communication with each other, and when the engine 1 and the operating region where the exhaust gas flow rate is large, The first vane 24 and the second vane 25 are connected to the first guide passage 30, the third guide passage 32, the second guide passage 31, and the fourth guide passage 31 shown in FIG.
The movable rod 26d is slid so that the movable rod 26d is placed in the open position where it does not communicate with the guide passage.

The housing 23 is formed with a waste gate 35 which is open to the atmosphere. This gate 35
It is closed by a wastegate valve 36 that is normally urged, and opens when the pressure in the turbine section 17 rises excessively. Here, the rod 37 that is linked to the waste gate valve 36 when the exhaust pressure rises
The valve is opened and closed by a diaphragm-type actuator (not shown) that moves the valve in the direction of the dashed arrow. However, the opening time of the waste gate valve 36 is the first
It is set later than the operation of the electromagnetic actuator 26c that opens the vane member 24 and the second vane member 25.

The control unit 27 shown in FIG.
It is well known that a main part of a microcomputer includes a ROM (read-on memory), a RAM (random access memory), a CPU (microprocessor), an input port and an output port, which are connected to each other by a bidirectional bus (not shown). Take a hard configuration. At the input port, a rotation speed sensor 38 that outputs a rotation speed Ne signal of the engine 1 as a driving state detection means of the engine 1, a load sensor 39 that outputs a load L signal of the engine 1, a cooling water temperature wt signal of the engine 1 are input. The temperature sensor 40 and the like for outputting are respectively connected via an AD converter (not shown). On the other hand, the actuator 26c is connected to the output port via a corresponding drive circuit (not shown). ROM
The control program shown in FIG. 7, the turbo operation state setting map shown in FIG. 8, and the like are stored in the (read-on memory).

The turbo operation state setting map shown in FIG.
It is made from the engine speed Ne and the engine load L such as the accelerator opening degree corresponding to the exhaust flow rate, and the area indicated by is a low flow rate area where the first vane 24 and the second vane 25 are in the closed position. The areas shown are the large flow rate areas in which the first vane 24 and the second vane 25 are in the open position.

The turbocharger 1 thus constructed
The operation of No. 3 will be described with reference to the supercharging pressure control routine shown in FIG. When the main switch (not shown) is turned on, the control unit 27 executes a well-known main routine (not shown) including fuel injection control and the like, and reaches the supercharging pressure control routine shown in FIG. 7 midway. Then, the control unit 27 takes in the detection signals of the engine speed Ne, the load L, etc. from the respective sensors, stores the obtained data in a predetermined area (step s1), and proceeds to step s2. In step s2, the turbocharger 1 shown in FIG.
It is set to one of the two operating regions according to the current rotation speed Ne and the load L according to the operating state setting map of No. 3, and the electromagnetic actuator 26c is driven according to the setting result in step s3. To return.

When the setting mode in step s2 is in the low flow rate range, the actuator 26c is not driven and the first
Since the vane member 24 and the second vane member 25 are still in the closed position shown in FIG. 3, the exhaust gas discharged from the engine 1 with a small flow rate is discharged from the exhaust outlets 10E, 10F to the first position.
It is introduced into the exhaust gas introducing portion 21 and the second exhaust gas introducing portion 22, respectively. The exhaust gas introduced into the first exhaust introduction part 21 flows into the flow path 34 through the first guide passage 30 and the third guide passage 32, and the exhaust gas introduced into the second exhaust introduction part 22 is divided into the second exhaust passage It separately flows into the flow passage 34 through the guide passage 31 and the fourth guide passage 33, and is guided to the turbine wheel 20. At this time, since the lower end portions (nozzle portions) B and C of the third and fourth guide passages are narrowed down, the flow velocity of the exhaust gas is sufficiently increased and applied to the turbine wheel 20. In addition, ignition orders # 1 and # 4 are not continuous.
The cylinders, # 2 and # 3 cylinders, have the same exhaust manifolds 10A and 10B, respectively, and the exhaust gas from each exhaust manifold is partitioned by partition walls 10D.
Also, since it is introduced into the housing 23 via the guide passage, it is possible to prevent exhaust interference of the exhaust gas introduced into the housing, to positively utilize exhaust pulsation, and to improve efficiency even in a low flow rate operation state. Turbine wheel 20
Can be rotated.

On the other hand, when the setting mode in step s2 is in the large flow area of, the actuator 26c is energized and driven, and the rod 26d shown in FIG. 1 slides in the direction of arrow a to the closed position in FIG. First vane member 24
And the 2nd vane member 25 rotates to the open position shown in FIG. Then, the second guide passage 31 that was in communication with the second exhaust introduction part 22 moves to communicate with the first introduction part 21, and the second vane member 25 rotates counterclockwise.
The communication between the second guide passage 31 and the fourth guide passage 33 is released. Therefore, the exhaust gas flowing into the first exhaust gas introducing portion 21 is guided to the second guide passage 31 and the vane 25B to the flow path 34, and the exhaust gas flowing into the second exhaust gas introducing portion 22 is guided to the vane 24B. Of the turbine wheel 20.
To rotate.

That is, when the exhaust gas flow rate increases, the first
Lower end portions (nozzle portions) of the third and fourth guide passages 32 and 33 with respect to the flow rate of exhaust gas flowing through the opening area A corresponding to the total opening cross-sectional area of the exhaust gas introducing portion 21 and the second exhaust gas introducing portion 22.
The diaphragm effect by B and C (see FIG. 3) is not performed. As a result, the exhaust resistance due to the lower end portions (nozzle portions) B and C can be avoided, and the exhaust resistance at a large flow rate of the exhaust gas can be reduced, and a large amount of exhaust gas can be applied to the turbine wheel 20 at once.

By the way, when the exhaust gas flow rate is further increased due to an inadvertent opening operation of the accelerator, etc., and the pressure in the housing 23 becomes excessively high, a diaphragm type actuator (not shown) is actuated to activate the waist. The gate valve 36 is opened, the pressure in the housing 23 is reduced, and overrun of the turbine wheel 20 due to supercharging is prevented.

Here, the waste gate valve 36 is opened and closed by a diaphragm type actuator.
It is also possible to open and close with an electromagnetic solenoid. In that case, steps s4 and s5 surrounded by a two-dot chain line are added to the supercharging pressure control routine shown in FIG. 7, and a region larger than the region is set in the map shown in FIG. When is selected according to the rotation speed Ne and the load L, the supercharged state may be determined and the electromagnetic solenoid may be driven to open the waste gate valve 36. The first vane member 24 and the second vane member 2
If supercharging can be avoided by the opening / closing operation of 5, it is not necessary to install the wastegate valve 36.

In the above-described embodiment, by operating the first vane member 24 and the second vane member 25 with the same electromagnetic solenoid, there are two positions, the closed position shown in FIG. 3 and the open position shown in FIG. Although controlled, a stepping motor may be used instead of the electromagnetic solenoid. in this case,
As shown in FIG. 6, the gear 3 is attached to the outer circumference of each rotary shaft 28, 29.
8 and 39 are provided, and the drive shafts 40a and 41a of the stepping motors 40 and 41 mesh with the gears 38 and 39, respectively.
2 and 43 are fixed and the rotating shafts 28 and 29 are driven.

In the stepping motors 40 and 41, in addition to the closed position shown in FIG. 3 and the open position shown in FIG. 4, the vane 2 shown in FIG.
4A, 24B sandwiches the partition wall 10D, and vanes 25A, 25
It is controlled by the control unit 27 so that B occupies the neutral position where it sandwiches the vane 24A. in this case,
In the turbo operation state setting map recorded in the control unit 27, as shown in FIG. 9, three areas of are set. A region indicated by is a low flow rate region in which the first vane 24 and the second vane 25 are in the closed position, and a region indicated by is a region in which the first vane 24 and the second vane 25 are in the open position. Is the first vane 24 and the second
Each of the large flow rates with the vane 25 in the neutral position is shown.

With such a configuration, when the supercharging pressure control routine shown in FIG. 7 reaches step s2 and the basin is set, the first vane member 24 and the second vane member 25 are set.
Is held in the closed position shown in FIG. 3, and when the area is set, the stepping motors 40, 41 are driven to position the first vane member 24 and the second vane member 25 in the open position shown in FIG. To do. Further, when the area indicated by is set in step s2, the stepping motors 40 and 41 are driven, and the first vane member 24 sandwiches the partition wall 10D and the second vane member 2 as shown in FIG.
5 occupies the neutral position with the vane 24A in between. Then, the exhaust gas introduced into the first exhaust introduction part 21 is branched into the first guide passage 30 and the second guide passage 31 by the vane 24A. The exhaust gas introduced into the first guide passage 30 is divided into the third guide passage 32 and the fourth guide passage 33 by the vane 25A and is guided to the turbine wheel 20 from the nozzle portions B and C through the passage 34. The exhaust gas introduced into the second guide passage 31 is branched by the vane 25B, guided from the fourth guide passage 33 to the turbine wheel 20 through the flow passage 34 from the nozzle portion C, and is also directly guided to the turbine wheel 20. .

On the other hand, the exhaust gas introduced into the second exhaust introduction portion 22 is guided to the second guide passage 31 and the turbine wheel 20 by the vane 24B. The exhaust gas introduced into the second guide passage 31 is guided to the turbine wheel 20 and the fourth guide passage 33 by the vane 25B. The exhaust gas guided to the fourth guide passage 33 is applied to the turbine wheel 20 from the nozzle portion C via the flow passage 34. That is, the positions of the first vane member 24 and the second vane member 25 shown in FIGS. 3 and 4 are the housings without interfering with the exhaust gas guided to the first exhaust introduction part 21 and the second exhaust introduction part 22. While it is a position where the exhaust pulsation can be positively utilized by introducing into 23, the neutral position of the first vane member 24 and the second vane member 25 shown in FIG. The exhaust passages for the first exhaust introduction portion 21 and the second exhaust introduction portion 22 are enlarged, and the passages for the turbine wheel 20 are increased.

Therefore, the exhaust gas introduced into the first exhaust gas introducing section 21 and the second exhaust gas introducing section 22 is introduced into the respective introducing sections 21, 22.
When it passes through, it is guided to the turbine wheel 20 through the common guide passage skein passages 34 and is directly guided to the turbine wheel 20, so that the exhaust resistance can be reduced and a large amount of exhaust gas can be discharged. can do.

In the above-described embodiment, the first vane member 24 and the second vane member 25 are each composed of two vanes 24A, 24B and 25A, 25Bb.
Although the four guide passages from No. to No. 4 are configured, the present invention is not limited to this. For example, three exhaust gas introducing portions are formed by partition walls in the housing 23, three first vanes are provided on the first rotating shaft 28 to serve as first guide portions, and the exhaust gas introducing portions are respectively partitioned by the first guide portions. A first passage means forming a first passage formed of three passages communicating with the section, and three second vanes fixed to the second rotating shaft 28 to form a second guide portion. A second passage means that is partitioned and forms a second passage formed of three passages that respectively communicate with the first passage formed of the above three passages is formed in the housing 23, and the first passage means and the second passage means are formed. The rotation of the control unit 27 may be controlled by the control unit 27. In this case, since the six passages are formed by the three passages forming the first passage and the three passages forming the second passage, the flow rate of the exhaust gas can be controlled more finely.

[0029]

According to the present invention, the exhaust gas from the exhaust manifold connected to the cylinders whose ignition order is not continuous in the multi-cylinder internal combustion engine is passed through the individual guide passages formed by the first vane member and the second vane member. Since the exhaust gas is guided to the turbine wheel, exhaust gas interference can be prevented, and exhaust gas can be introduced into the housing by utilizing exhaust pulsation, and the turbine wheel can be efficiently rotated even with a low flow rate of exhaust gas. Further, since the size of the flow passage of the guide passage is adjusted by rotating the first vane member and the second vane member according to the operating state of the internal combustion engine, the exhaust resistance can be adjusted.

Therefore, it is intended to provide a variable capacity turbocharger capable of preventing exhaust interference in the variable capacity turbocharger, efficiently introducing exhaust gas into a turbine over a wide range, and rotating a turbine wheel. The object of the present invention can be achieved.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a variable capacity turbocharger showing an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram showing an engine system equipped with a variable displacement turbocharger of the present invention.

FIG. 3 is an enlarged view showing a closed position of a first vane member and a second vane member.

FIG. 4 is an enlarged view showing an open position of a first vane member and a second vane member.

FIG. 5 is an enlarged view showing a neutral position of the first vane member and the second vane member.

FIG. 6 is a plan view showing an example of a drive mechanism for a first vane member and a second vane member.

FIG. 7 is a flowchart of a supercharging pressure control routine executed by the control means.

FIG. 8 is a characteristic diagram of a turbocharger operating region setting map stored in the control means.

FIG. 9 is a characteristic diagram of an operating region setting map of a turbocharger used when controlling the first vane member and the second vane member to three positions.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Multi-cylinder internal combustion engine 10A, 10B Exhaust manifold 10C Collecting part 10D Partition wall 10E First exhaust outlet 10F Second exhaust outlet 13 Variable capacity turbocharger 20 Turbine wheel 21 First exhaust introducing part 22 Second exhaust introducing part 23 Housing 28 28th 1 Rotating Shaft 24 First Vane Member 25 Second Vane Member 26 Drive Member 27 Control Means 30 First Guide Passage 31 Second Guide Passage 32 Third Guide Passage 33 Fourth Guide Passage Ne Revolution of Internal Combustion Engine L Exhaust Flow Rate ( load)

Claims (6)

[Claims] Claim: What is claimed is: 1. A first and a second partition which are partitioned by partition walls which respectively communicate with first and second exhaust outlets formed in a collecting portion of an exhaust manifold provided for each cylinder of a multi-cylinder internal combustion engine whose ignition order is not continuous. A housing having two exhaust gas introducing portions and housing a turbine wheel, and being curved along the turbine wheel,
A first end of which a downstream end is rotatably supported by the housing.
Two first vane members fixed to the rotating shaft and forming first and second guide passages communicating with the first and second exhaust gas introducing portions, respectively, the turbine wheel and the first vane member.
Third and third curved members are curved along the vane member and have their downstream ends fixed to a second rotating shaft rotatably supported by the housing so as to communicate with the first and second guide passages, respectively. A variable capacity turbocharger comprising: two second vane members forming a fourth guide passage; and control means for switching the rotational positions of the first vane member and the second vane member. 2. The variable capacity turbocharger according to claim 1, wherein the control means switches the rotational positions of the first vane member and the second vane member according to the rotational speed of the internal combustion engine. . 3. The control means switches the rotational positions of the first vane member and the second vane member in accordance with the exhaust flow rate of the exhaust gas of the internal combustion engine.
The variable capacity turbocharger described. 4. The variable capacity turbocharger according to claim 1, wherein the first and second rotating shafts are rotated and switched by a single driving member. 5. The variable displacement turbocharger according to claim 1, 2 or 3, wherein the control means switches the rotational positions of the first and second vane members in three stages. 6. A first and second exhaust gas introduction section partitioned by partition walls which respectively communicate with first and second exhaust gas outlets formed in a collection section of an exhaust manifold of a cylinder whose ignition sequence is not continuous in a multi-cylinder internal combustion engine. A housing for accommodating the turbine wheel, and a first rotation shaft rotatably supported by the housing.
While being curved along the turbine wheel,
A plurality of first end portions each having a plurality of first vanes fixed to the first rotation shaft, the downstream end portion of which is partitioned by the first guide portions and communicated with the plurality of exhaust gas introducing portions. First passage means forming a first passage, and a second rotation shaft rotatably supported by the housing,
The turbine wheel and a second guide portion having a plurality of second vanes curved along the first vane and having a downstream end fixed to the second rotating shaft, and the second guide portion. And second control means for switching the rotational positions of the first passage means and the second passage means. A variable-capacity turbocharger characterized by that.