JP2005351220A - Intake device for internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an intake device for an internal combustion engine, in which an introducing port to a recirculating exhaust gas intake pass can approach a throttle valve, weight of an intake system is reduced, and installation space and cost can be reduced. <P>SOLUTION: Primary and secondary side branch intake passes 21, 22 are connected to the intake manifolds 18, 19 of the V-shape internal combustion engine 11, superchargers 37, 38 for supercharging intake are arranged respectively in the course of both the branch intake passes 21, 22, and intercoolers 25, 26 are arranged in both the branch intake passes 21, 22 on a further downstream sides of the superchargers 37, 38. The throttle valves 27, 28 are provided in both the branch intake passes on the downstream sides of both the intercoolers 25, 26. An exhaust circulating device 43 is provided which circulates a part of exhaust gas to a confluent intake pass 29 on the further downstream sides of both the throttle valves. Primary and secondary side branch intake passes 21A, 22A between both the intercoolers 25, 26 and both the throttle valves 27, 28 are communicated with each other through a communicating pass 54. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an intake device for an internal combustion engine, and more particularly, to a throttle valve for exhaust gas recirculated from an exhaust gas recirculation passage of an EGR (Exhaust Gas Recirculation) device to an intake system in a V-type internal combustion engine. The present invention relates to an intake device for an internal combustion engine that can improve the durability of a throttle valve by suppressing the blow-back of the exhaust gas and can appropriately control the supply amount of the recirculated exhaust gas to the intake system.

  In a V-type internal combustion engine, primary and secondary cylinder heads are mounted on a cylinder block having primary and secondary cylinder banks (cylinder rows) arranged in a V shape in a side view. In some V-type internal combustion engines, an intake path and an exhaust path are branched into two systems corresponding to each cylinder bank, and a supercharger or the like is also provided with two systems. The details are as follows. Air is introduced into the intake manifold of the V-type internal combustion engine through the primary side and secondary side branch intake passages. In the middle of the two branched intake passages, primary and secondary superchargers are provided to improve the startability and output of the vehicle by supercharging intake air using the exhaust gas pressure of the internal combustion engine. It has been. In the middle of the two branch intake passages, an intercooler for cooling the supercharged intake air is provided so as to be positioned downstream of the two superchargers, and the two branch intake passages on the downstream side of the two intercoolers are provided. Each has a throttle valve. In this way, as a case where the intake and exhaust paths are dual systems corresponding to each cylinder bank, when the intake and exhaust paths are made one system, the accompanying turbocharger and throttle valve are enlarged, and the mountability and cost, The case where responsiveness becomes disadvantageous is mentioned.

Further, an internal combustion engine, particularly a diesel engine, is provided with an exhaust gas recirculation (EGR) device that recirculates part of the exhaust gas to the intake passage in order to reduce nitrogen oxide (NOx) contained in the exhaust gas. ing. Generally, the recirculated exhaust gas is recirculated into the intake passage on the downstream side of the throttle valve. In the above-described internal combustion engine having a branch intake / exhaust path for each cylinder bank, not only a new air amount but also a recirculated exhaust gas amount affects the intake amount of each branch intake passage. For this reason, a structure in which exhaust gas is equally extracted upstream of a plurality of superchargers, or a structure in which individual EGR devices are provided in each of the branch intake and exhaust paths is known. (Patent Document 1 discloses a structure in which two superchargers are provided, and a reflux exhaust gas is taken out from each exhaust passage upstream thereof. Patent Document 2 discloses a separate exhaust gas recirculation corresponding to a branch intake and exhaust path. An EGR device with a passage and a control valve is disclosed.)
On the other hand, in a V-type internal combustion engine having four primary cylinders, four secondary cylinders, and eight cylinders in total, an odd number of first, third, fifth, and seventh cylinders are arranged on the primary side. Even-numbered second, fourth, sixth, and eighth cylinders are arranged. The first to eighth cylinders are ignited in consideration of the balance of the motion system of the internal combustion engine, for example, the first, second, seventh, third, fourth, fifth, sixth, eighth cylinders. It is usually set in order, and when viewed from the primary side and secondary side cylinder banks, it is customary that ignition is not performed at equal intervals. Therefore, since there are unbalanced pulsations caused by continuous explosion in each cylinder in the intake system and the exhaust system, variation in the amount of recirculated exhaust gas supplied to each cylinder increases. That is, the pulsation of the intake system has a large fluctuation range and is irregular as shown by a two-dot chain line in the graph of FIG. 2 in which the horizontal axis represents the crank angle of the internal combustion engine and the vertical axis represents the pressure.

Further, the unbalanced pulsation of the exhaust system is generated in the same manner as the unbalanced pulsation of the intake system (not shown).
In order to alleviate the aforementioned unbalanced pulsation of the intake system, a configuration is known in which the primary and secondary intake manifolds communicate with each other on the downstream side of the inlet of the recirculated exhaust gas to the intake passage. Yes. (See Patent Document 3)
JP 2003-129874 A Special table 2002-539358 gazette Japanese Patent Laid-Open No. 04-232326 "

  As described above, by connecting the primary and secondary intake manifolds through the communication passage, unbalanced pulsations with a large fluctuation range of the intake system are alleviated, so intake air from the primary and secondary exhaust recirculation passages. When the recirculated exhaust gas is directly introduced into the manifold, fluctuations in the recirculated exhaust gas amount are suppressed, and variations in the recirculated exhaust gas amount supplied to each cylinder can be reduced. However, if the recirculated exhaust gas inlet is in communication with the intake passage immediately after the throttle valve, the remaining unbalanced pulsation in the intake passage and the unbalanced pulsation of the exhaust system are alleviated. As a result, the recirculated exhaust gas is blown back to the throttle valve side, and the throttle valve deteriorates due to the high heat of the recirculated exhaust gas, resulting in lower durability. There is also a problem that the variation in the amount of recirculated exhaust gas supplied to each cylinder further increases due to the reflow phenomenon of the recirculated exhaust gas toward the throttle valve.

  By the way, from the viewpoint of properly mixing the new air and the recirculated exhaust gas, the inlet of the recirculated exhaust gas to the intake passage is separated from the intake manifold and is brought closer to the throttle valve, and the recirculated exhaust gas inlet is connected to the intake manifold. It is necessary to set the intake passage to a predetermined length. In order to avoid the deterioration of the throttle valve due to the recirculation of the recirculated exhaust gas, it is necessary to set a long intake passage from the throttle valve to the recirculated exhaust gas inlet. Therefore, in the conventional intake device of an internal combustion engine, if it is attempted to avoid the deterioration of the throttle valve, the intake passage from the throttle valve to the intake manifold becomes longer, and its weight increases, which is disadvantageous in terms of installation space and cost. There's a problem.

Furthermore, the structure which connects the primary side and secondary side intake passage between the compressor part of a primary and secondary side supercharger, and a primary side and a secondary side intercooler by a communicating path is also proposed.
However, in the above-described configuration, an unbalanced pulsation of the intake system causes the intake air in the primary and secondary intake passages to flow back to the compressor parts of the primary and secondary turbochargers, resulting in a compressor surge. There is a problem.

  The first object of the present invention is to eliminate the unbalanced pulsation of the intake system generated in the intake passage between the primary and secondary throttle valves and the intake manifold, and to introduce the recirculated exhaust gas into the intake passage. Can be brought closer to the throttle valve, the weight of the intake system can be reduced, the installation space and cost can be reduced, and the supply amount of the recirculated exhaust gas to each cylinder can be controlled appropriately It is to provide an air intake device.

  A second object of the present invention is to provide an intake device for an internal combustion engine that can further improve the first object by eliminating the unbalanced pulsation of the exhaust system that occurs in the primary side and secondary side exhaust gas recirculation passages. There is.

  In order to solve the above-mentioned problems, the invention described in claim 1 has a primary side and secondary side cylinder bank configured by mounting a primary side and a secondary side cylinder head on a V-shaped cylinder block. A primary side and a secondary side branch intake passage are connected to an intake manifold of a V-type internal combustion engine, and a supercharger for supercharging intake air is provided in the middle of both of the branch intake passages, downstream of the supercharger. Cooling means are provided in both branch intake passages on the side, throttle valves are provided in both branch intake passages on the downstream side of both cooling means, and a part of the exhaust gas is recirculated to the intake passage on the downstream side of both throttle valves. In the intake device for an internal combustion engine provided with the exhaust gas recirculation device, the gist is that the primary side and secondary side branch intake passages between the cooling means and the throttle valves are communicated with each other by a communication passage.

  According to a second aspect of the present invention, there is provided a supercharger for connecting a primary side and a secondary side branch intake passage to an intake manifold of a V-type internal combustion engine, and for supercharging intake air in the middle of both the branch intake passages. An internal combustion engine provided with an exhaust gas recirculation device that is provided with throttle valves in both branched intake passages downstream of the turbocharger and recirculates part of the exhaust gas to the intake passage downstream of the throttle valves In the intake system of the present invention, a communication passage that communicates the primary side and secondary side branch intake passages is provided adjacent to the throttle valves between the turbochargers and the throttle valves. .

  According to a third aspect of the present invention, in the first or second aspect, downstream ends of the primary side and secondary side branched intake passages are connected to a merged intake passage, and a downstream end of the merged intake passage is formed by a branched passage. The gist is that the downstream end of the exhaust gas recirculation passage of the exhaust gas recirculation device is connected to the primary side and secondary side intake manifolds and communicates with the merged air intake passage.

  According to a fourth aspect of the present invention, in any one of the first to third aspects, the exhaust gas recirculation device includes a primary side and secondary side exhaust gas recirculation passage connected to the primary side and secondary side exhaust manifolds of the internal combustion engine. And primary and secondary flow control valves respectively provided in the exhaust recirculation passages, and an exhaust cooler provided on the downstream side of the flow control valves of the primary and secondary exhaust recirculation passages. It is a summary.

  According to a fifth aspect of the present invention, in the fourth aspect, the downstream ends of the primary side and secondary side exhaust gas recirculation passages are connected to the upstream end of the merged exhaust gas recirculation passage inside the exhaust cooler, and the combined exhaust gas recirculation flows The gist is that the downstream end of the passage is connected to the intake passage on the downstream side of the throttle valves.

  A sixth aspect of the present invention is that, in any one of the first to fifth aspects, the communication path communicates with a primary side and a secondary side branch intake path in the vicinity of the throttle valves. And

  The gist of a seventh aspect of the present invention is that, in any one of the first to sixth aspects, the downstream end of the exhaust gas recirculation passage communicates with the intake passage in the vicinity of both throttle valves. .

  The invention according to any one of claims 1 to 3 to 7 occurs in the intake system because the primary side and secondary side branch intake passages between the cooling means and the throttle valves are communicated by the communication passages. Unbalanced pulsations with large fluctuations can be eliminated. For this reason, it is possible to reduce the amount of recirculation of the recirculated exhaust gas introduced into the intake passage toward the throttle valve, and to bring the recirculated exhaust gas into the intake passage closer to the throttle valve. Therefore, the length dimension of the intake passage between the throttle valve and the introduction port can be shortened to reduce its weight, and the installation space and cost can be reduced. Furthermore, since the amount of recirculation of the recirculated exhaust gas is reduced, the amount of exhaust gas supplied to each cylinder can be controlled appropriately.

  In the invention according to claim 2, a communication passage that communicates the primary side and secondary side branch intake passages is provided between the turbochargers and the throttle valves adjacent to the throttle valves. Unbalanced pulsations with a large fluctuation range generated in the intake system can be eliminated. For this reason, there exists an effect similar to the effect described in Claim 1.

  In addition to the effect of the invention described in claim 1 or 2, the invention described in claim 3 allows the exhaust gas supplied from the exhaust gas recirculation passage to the merged intake passage to be a new intake air inside the merged intake passage. Properly mixed and supplied to the intake manifold.

  In addition to the effect of the invention according to any one of claims 1 to 3, the invention according to claim 4 is provided through the primary and secondary flow control valves from the primary and secondary exhaust recirculation passages. Thus, the recirculated exhaust gas can be properly supplied to the intake passage.

  According to the fifth aspect of the present invention, since the primary side and secondary side exhaust gas recirculation passages are communicated with each other by the communication passage, any unbalanced pulsation with a large fluctuation range of the exhaust system is eliminated. The effects of the invention described in one item can be further improved.

  The invention according to claim 6 eliminates unbalanced pulsation in the intake passage downstream of the throttle valve since the communication passage communicates with the primary side and secondary side branched intake passages in the vicinity of both throttle valves. The effect can be enhanced.

An embodiment of an intake device for an internal combustion engine embodying the present invention will be described below with reference to FIGS.
As shown in FIG. 1, the primary and secondary cylinder blocks 12 and 13 having a plurality of cylinders 12a to 12d and 13a to 13d constituting the internal combustion engine 11 are integrally formed in a V shape as a whole. Primary and secondary cylinder heads 14 and 15 are mounted on the secondary cylinder blocks 12 and 13 so as to cover the cylinders 12a to 12d and 13a to 13d, thereby forming primary and secondary cylinder banks. ing. Fuel injection valves 16 to 16 are attached to the primary and secondary cylinder heads 14 in correspondence with the cylinders 12a to 12d, and fuel to the secondary cylinder head 15 in correspondence with the cylinders 13a to 13d. Injection valves 17 to 17 are attached. A primary side intake manifold 18 is connected to the primary side cylinder head 14, and a secondary side intake manifold 19 is connected to the secondary side cylinder head 15. The primary and secondary intake manifolds 18 and 19 are supplied with new air from the primary and secondary branch intake passages 21 and 22. A muffler 24 is connected to the upstream side of the primary and secondary branch intake passages 21 and 22 via a basic intake passage 23. In the middle of the primary and secondary branch intake passages 21 and 22, the intake air having heat superposed by the compressor units 40 and 42 of the primary and secondary superchargers 37 and 38 described later is cooled. Primary and secondary intercoolers 25 and 26 are interposed as cooling means for increasing the air density.

  Primary and secondary throttle valves 27 and 28 are interposed in the middle of the primary and secondary branch intake passages 21 and 22. The downstream ends of the primary and secondary branch intake passages 21 and 22 are connected to the upstream end of the merging intake passage 29, and the downstream end of the merging intake passage 29 is connected to the primary and secondary intake manifolds 18 by the branch passage 30. , 19.

  A primary exhaust manifold 31 is connected to the primary cylinder head 14, and a secondary exhaust manifold 32 is connected to the secondary cylinder head 15. A primary exhaust passage 33 is connected to the primary exhaust manifold 31, and a secondary exhaust passage 34 is connected to the secondary exhaust manifold 32. Mufflers 35 and 36 are connected to the primary and secondary exhaust passages 33 and 34. A turbine part 39 constituting a primary supercharger 37 is interposed in the middle of the primary side exhaust passage 33, and a compressor part 40 constituting the primary side supercharger 37 is placed in the middle of the primary side branch intake passage 21. Intervened. Similarly, a turbine part 41 constituting a secondary supercharger 38 is interposed in the middle of the secondary exhaust passage 34, and the compressor part 42 constituting the secondary supercharger 38 is connected to the secondary side supercharger 38. It is interposed in the middle of the branch intake passage 22. The primary and secondary superchargers 37 and 38 are variable nozzle turbochargers that are actuated by exhaust flows flowing through the primary and secondary exhaust passages 33 and 34.

Next, the exhaust gas recirculation (EGR) device 43 will be described.
The upstream ends of the primary and secondary exhaust recirculation passages 44 and 45 constituting the exhaust recirculation device 43 are connected to the primary and secondary exhaust manifolds 31 and 32. Catalytic devices 46 and 47 for purifying NOx in the exhaust gas are connected in the middle of the primary and secondary exhaust recirculation passages 44 and 45, and as downstream and primary flow control valves. EGR valves 48 and 49 are connected. The downstream ends of the primary and secondary exhaust recirculation passages 44 and 45 are connected to the upstream end of the merged exhaust recirculation passage 50. The downstream end of the merged exhaust gas recirculation passage 50 is connected to the upstream end of the merged intake passage 29 of the intake system. A connection portion between the merged intake passage 29 and the merged exhaust gas recirculation passage 50 serves as a recirculation exhaust gas introduction port 51. An exhaust cooler 52 for cooling the high-temperature exhaust gas and promoting the reduction of NOx is attached to the connection portion between the primary and secondary exhaust recirculation passages 44 and 45 and the combined exhaust recirculation passage 50.

  The odd-numbered first, third, fifth, and seventh cylinders 12a to 12d of the primary-side cylinder block 12 and the even-numbered second, fourth, sixth, and eighth cylinders 13a of the secondary-side cylinder block 13 The ignition order of ˜13d is, for example, the first, second, seventh, third, fourth, fifth, sixth, in consideration of the balance of the motion system of the internal combustion engine as described in the background art section. The cylinders are set in the order of the eighth cylinder, and the secondary cylinder blocks 12 and 13 do not ignite at equal intervals. Therefore, unbalanced pulsations with a large fluctuation width due to continuous explosion in each cylinder are generated in the intake system and the exhaust system, respectively. The pulsation of the intake system is indicated by a two-dot chain line in the graph of FIG.

Next, a configuration for reducing the above-described unbalanced pulsation of the intake system will be described.
The primary side branch intake passage 21A between the primary side intercooler 25 and the primary side throttle valve 27, and the secondary side branch intake passage 22A between the secondary side intercooler 26 and the secondary side throttle valve 28 are provided according to the present invention. It communicates with the communication path 54 which is a principal part structure. The communication passage 54 eliminates unbalanced pulsation of the intake system generated in the primary and secondary branch intake passages 21A and 22A, the merged intake passage 29, and the branch passage 30.

Next, a control system that controls each part of the internal combustion engine 11 will be described.
Primary and secondary air flow meters 55 and 56 are provided on the downstream side of the compressor portions 40 and 42 in the primary and secondary branch intake passages 21 and 22, and the primary and secondary air flow meters 55 and 56 are provided. The detection signals of the air amounts in the primary and secondary intake passages 21 and 22 detected by the above are input to an electronic control unit (ECU) 57 having a computer.

  Although not shown, the electronic control unit 57 is connected to various sensors that detect the operating state of the internal combustion engine 11 and the traveling state of the vehicle. As this sensor, an accelerator sensor for detecting the accelerator opening of the accelerator pedal, a rotation speed sensor for the internal combustion engine 11, an engine coolant temperature sensor, a throttle sensor for detecting the opening degree of the primary and secondary throttle valves 27 and 28, a vehicle speed sensor and so on.

  The primary and secondary superchargers 37 and 38 are used to detect signals of air amounts in the primary and secondary intake passages 21 and 22 detected by the primary and secondary airflow meters 55 and 56 and other internal combustion engines. The vane opening degree of the turbine portions 39 and 41 is controlled by the control signal output from the electronic control unit 57 based on the detection signal of the engine operating state and the vehicle traveling state. Thereby, the optimum supercharging pressure is always obtained, and the torque in the low speed region and the starting performance are improved.

  Based on detection signals from various sensors that detect the operating state of the internal combustion engine 11 and the traveling state of the vehicle, the electronic control unit 57 performs an exhaust gas recirculation rate suitable for the current engine operating state (recycle with respect to the total intake air amount). Calculate the ratio of the circulating exhaust volume). Then, based on the exhaust gas recirculation rate, the opening degree drive command value concerning the opening degree of the primary and secondary side EGR valves 48 and 49 is calculated. Based on this opening degree drive command value, the opening degree of both EGR valves 48 and 49 is controlled, and exhaust gas recirculation suitable for the engine operating state is executed. For example, when the internal combustion engine 11 shifts to an idle operation state, the electronic control unit 57 controls the primary and secondary EGR valves 48 and 49 so as to be almost fully opened. As a result, the exhaust gas recirculation rate is set to be larger than that during high load operation, for example, and a large amount of exhaust gas is recirculated, so that an increase in engine combustion temperature is suppressed and NOx emission is suppressed.

According to the intake device for an internal combustion engine of the above embodiment, the following effects can be obtained.
(1) In the above embodiment, the primary side branch intake passage 21A between the primary side intercooler 25 and the primary side throttle valve 27, and the secondary side branch intake passage between the secondary side intercooler 26 and the secondary side throttle valve 28. 22A was communicated with the communication path 54. Therefore, unbalanced pulsation of the intake system generated in the primary and secondary intake manifolds 18 and 19 can be eliminated, and the pulsation is introduced from the merging exhaust gas recirculation passage 50 into the merging intake passage 29 via the introduction port 51. Further, the amount of blowback to the primary and secondary throttle valves 27, 28 can be suppressed. Therefore, the introduction port 51 can be brought close to the primary and secondary throttle valves 27 and 28, the length of the combined intake passage 29 is shortened, the weight of the intake system is reduced, and the installation space and cost are reduced. be able to.

  (2) In the above embodiment, since the amount of recirculation of the recirculated exhaust gas to the primary and secondary throttle valves 27 and 28 is suppressed, the amount of exhaust gas supplied can be controlled appropriately. The primary and secondary throttle valves 27 and 28 can be prevented from deteriorating due to the high heat of the recirculated exhaust gas, and the primary and secondary throttle valves 27 and 28 can be prevented from being contaminated by impurities contained in the exhaust gas. Can be increased.

  (3) In the above embodiment, the downstream end of the combined exhaust gas recirculation passage 50 of the exhaust gas recirculation device 43 communicates with the upstream end portion of the combined intake air passage 29. For this reason, the length dimension of the merging intake passage 29 can be set to the longest in a limited installation space, and the new air and the recirculated exhaust gas can be mixed efficiently and appropriately.

  (4) In the above embodiment, the downstream ends of the primary side and secondary side exhaust recirculation passages 44 and 45 are connected to the combined exhaust recirculation passage 50. For this reason, the primary and secondary side exhaust gas recirculation passages 44 and 45 are connected to each other by the merged exhaust gas recirculation passage 50, and the unbalanced pulsation of the exhaust system generated in the primary and secondary side exhaust manifolds 31 and 32 occurs. It will be resolved. Accordingly, the unbalanced pulsation acting on the recirculated exhaust gas supplied from the merged exhaust gas recirculation passage 50 to the merged intake air passage 29 through the inlet 51 is eliminated, and the primary and secondary sides of the recirculated exhaust gas in the merged intake air passage 29 are eliminated. The amount of blowback to the throttle valves 27 and 28 is reduced. Accordingly, the introduction port 51 can be further moved closer to the primary and secondary throttle valves 27 and 28, and the effect (1) described above can be enhanced.

In addition, you may change the said embodiment as follows.
As shown in FIG. 3, the primary and secondary branch intake passages 21 and 22 downstream of the primary and secondary throttle valves 27 and 28 are directly communicated with the primary and secondary intake manifolds 18 and 19, The primary and secondary side exhaust recirculation passages 44 and 45 may be communicated with the primary and secondary side branch intake passages 21 and 22 without joining. In this embodiment, a communication path that directly communicates the primary and secondary intake manifolds 18 and 19 may be provided.

A supercharger that uses the rotational motion of the internal combustion engine 11 may be used as the supercharger.
The placement position of the introduction port 51 is preferably provided at the upstream end of the merging intake passage 29, but may be set at an intermediate portion of the merging intake passage 29.

  The communication passage 54 may communicate with the primary and secondary branch intake passages 21A and 22A adjacent to the primary and secondary throttle valves 27 and 28. Further, the communication path 54 may be disposed at a plurality of locations.

The downstream ends of the primary and secondary side exhaust gas recirculation passages 44 and 45 may be separated from the merging intake passage 29 and communicate with each other.
In the above embodiment, the present invention is applied to the internal combustion engine 11 equipped with the variable capacity primary and secondary superchargers 37, 38, but the internal combustion engine 11 equipped with the primary and secondary superchargers that are not variable capacity. It can also be applied to.

O You may actualize to the internal combustion engine 11 which abbreviate | omitted any one of the primary and secondary side exhaust gas recirculation passages 44 and 45.
A primary manifold and a secondary side intake manifold 18, 19 may be integrated into an intake manifold.

  The primary and secondary intercoolers 25 and 26 as cooling means may be omitted. In this case, between the turbochargers 37 and 38 and the throttle valves 27 and 28, adjacent to the throttle valves 27 and 28, the primary side and secondary side branch intake passages 21A and 21B are provided. A communication path 54 that communicates is provided. This another example also has the same effect as described above.

1 is a schematic plan view showing an embodiment of an intake device for an internal combustion engine according to the present invention. The graph which shows the relationship between the crank angle of an internal combustion engine, and the pressure of an intake system. The partial approximate body top view which shows another embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Internal combustion engine, 14, 15 ... Secondary side cylinder head, 18, 19 ... Primary side and secondary side intake manifold, 21, 21A, 22, 22A ... Primary side and secondary side branch intake passage, 29 ... Confluence intake Passage, 30 ... branch passage, 31, 32 ... primary and secondary exhaust manifolds, 37, 38 ... primary and secondary superchargers, 43 ... exhaust recirculation device, 44, 45 ... primary and secondary sides Exhaust gas recirculation passage, 50 ... Merge exhaust gas recirculation passage, 52 ... Exhaust cooler, 54 ... Communication passage.

Claims (7)

Primary and secondary branch intake passages in an intake manifold of a V-type internal combustion engine having a primary and secondary cylinder bank constructed by mounting primary and secondary cylinder heads on a V-shaped cylinder block And a supercharger for supercharging intake air in the middle of the two branch intake passages, cooling means are provided in both branch intake passages downstream of the supercharger, and downstream of both cooling means. In the intake device for an internal combustion engine provided with an exhaust gas recirculation device for providing a throttle valve in each of the two branched intake passages on the side and returning a part of the exhaust gas to the intake passage on the downstream side of the two throttle valves,
An intake system for an internal combustion engine, characterized in that a primary side and a secondary side branched intake passage between the cooling means and the throttle valves are communicated by a communication passage. A primary side and a secondary side branch intake passage are connected to an intake manifold of a V-type internal combustion engine, and a supercharger for supercharging intake air is provided in the middle of both of the branch intake passages, downstream of the supercharger. In the intake device for an internal combustion engine provided with an exhaust gas recirculation device for providing a throttle valve in each of the two branched intake passages on the side and returning a part of the exhaust gas to the intake passage on the downstream side of the two throttle valves,
An intake system for an internal combustion engine, characterized in that a communication passage that communicates a primary side and a secondary side branch intake passage is provided between both the turbochargers and both throttle valves, adjacent to both the throttle valves. . 3. The downstream end of the primary side and secondary side branch intake passages is connected to a merged intake passage, and the downstream end of the merged intake passage is connected to the primary side and secondary side intake manifolds by the branch passages. An intake system for an internal combustion engine, wherein the downstream end of an exhaust gas recirculation passage of the exhaust gas recirculation device is connected to the combined intake air passage. The exhaust gas recirculation device according to any one of claims 1 to 3, wherein the exhaust gas recirculation devices are respectively disposed in a primary side and a secondary side exhaust gas recirculation passage connected to a primary side and a secondary side exhaust manifold of the internal combustion engine, and both the exhaust gas recirculation passages. An internal combustion engine comprising: primary and secondary flow control valves provided; and an exhaust cooler provided downstream of the flow control valves of the primary and secondary exhaust recirculation passages. Intake device. 5. The downstream end of the primary side and secondary side exhaust gas recirculation passages is connected to the upstream end of the merged exhaust gas recirculation passage inside the exhaust cooler, and the downstream end of the merged exhaust gas recirculation passage is connected to both throttles. An intake device for an internal combustion engine, wherein the intake device is connected to an intake passage downstream of the valve. 6. The intake system for an internal combustion engine according to claim 1, wherein the communication passage communicates with a primary side and a secondary side branch intake passage in the vicinity of the throttle valves. The intake device for an internal combustion engine according to any one of claims 1 to 6, wherein a downstream end of the exhaust gas recirculation passage is communicated with the intake passage in the vicinity of both throttle valves.

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