JP2017180392A - Intake air distribution device of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve cooling efficiency by an intercooler in an intake air distribution device in which the intercooler and an intake manifold are integrated.SOLUTION: An intake air distribution device 4 is composed of an intercooler 11 and an intake manifold 12. The intercooler 11 is disposed in a state of vertically arranging cooling fins 15. An intake air introduction port 20 is disposed on an upper end of the intercooler 11. The intake air is blown out downward to an inlet space 18, and then turned to be directed to a cooling portion 17. Thus the intake air is widely diffused right and left in the inlet space 18. As a result, the intake air can be uniformly cooled by using the whole cooling portion 17. By disposing a mountain-shaped diffusion member 27, the uniform dispersibility is further improved.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an intake air distribution device in which an intake manifold and an intercooler are integrated.

  The integration of the intake manifold and the intercooler is disclosed in Patent Document 1, for example. In the case of a plate type (fin type) intercooler, plate-like cooling fins through which cooling water passes are arranged in multiple stages, and one side across the group of cooling fins forms an inlet space. The other side forms an exit space, and the intake air passes through the ventilation space between adjacent cooling fins, whereby heat is exchanged from the intake air to the cooling fins, thereby cooling the intake air.

  And in patent document 1, the inlet port is located on the line which connects inlet space and outlet space.

Japanese Patent No. 5283627

  Now, while the flow of intake air is straight, the opening area of the intake air inlet is much smaller than the area of the inlet space in the intercooler. Therefore, when the intake inlet is located on a line connecting the inlet space and the outlet space as in Patent Document 1, the intake air discharged from the intake inlet has a tendency to go straight to the outlet space with straightness. Because of this, there is concern about poor cooling performance. In other words, in Patent Document 1, only a part of the cooling unit composed of a group of cooling fins is used for cooling, and the intake air does not contact the cooling unit evenly, so that the function of the intercooler cannot be sufficiently extracted. .

  The present invention has been made in view of such a current situation, and it is intended to improve the cooling performance by sufficiently extracting the performance of the intercooler, and also to facilitate the intake of EGR gas and the countermeasure against condensed water. is there.

The present invention relates to an intake air distribution device in which the intercooler and the intake manifold are integrated.
“It has an intercooler that cools the intake air, and an intake manifold that distributes the intake air cooled by the intercooler to each intake port of the cylinder head,
The intercooler includes a cooling unit in which ventilation gaps and cooling fins are alternately arranged, and an inlet space located on one side across the cooling unit is an outlet located on the other side across the cooling unit And the inlet space and the outlet space are in communication with the group of the ventilation gaps,
In the intercooler, an intake inlet for taking intake air into the inlet space is opened in the direction in which the ventilation gap and the cooling fin are arranged, while the outlet space communicates with the intake manifold,
An EGR gas distribution passage is provided in the intake manifold or the outlet space. "
It is the composition.

  Although this invention has various aspects, as a suitable aspect, the spreading | diffusion member which spreads inhalation | air-intake in the inlet direction of a cooling part can be provided in entrance space. Further, as another aspect related to the EGR gas intake means, an EGR gas distribution passage is formed in the intake manifold, or an EGR gas distribution passage is formed by a pipe and disposed in the outlet space of the intercooler. it can.

  In the present invention, the intake air is introduced into the inlet space in the direction in which the cooling fins are arranged, changes direction, passes through the ventilation gap between the adjacent cooling fins, and moves toward the outlet space. When the direction is changed in the inlet space, the air flow is diffused in both the front direction and the height direction of the cooling unit composed of a group of cooling fins. To be high. As a result, the cooling performance can be improved and the filling efficiency can be improved.

  In other words, in the present invention, the inlet space can be effectively used as a buffer space in which the intake air diffuses, and the intake air can be spread as evenly as possible over the entire front surface (entire front surface) of the cooling unit made up of a group of cooling fins. . Providing the diffusing member as described above is particularly suitable because it becomes more certain that the diffusion member is evenly spread over the entire front surface of the cooling unit.

  Now, recirculation of EGR gas to the intake system is widely performed, and EGR gas is introduced into a surge tank or distributed and introduced into each branch pipe of the intake manifold. In the present invention, since the EGR gas outlet is provided in the intake manifold or the outlet space, the cooling fins can be prevented from being contaminated with the EGR gas.

  If the distribution passage is provided in the intake manifold, the recirculation amount of the EGR gas to each intake port can be equalized as much as possible. Similarly, even if an EGR gas distribution passage is formed by a pipe and is disposed in the outlet space of the intercooler, the EGR gas can be evenly distributed to each intake port by being placed on the flow of intake air.

1 is a schematic plan view of an internal combustion engine. It is a rough isolation | separation perspective view of an air intake distribution apparatus. FIG. 3 is a sectional view taken along line III-III in FIG. 1. FIG. 4 is a sectional view taken along line IV-IV in FIG. 1. (A) is a longitudinal cross-sectional front view of the principal part of 2nd Embodiment, (B) is a BB view plane sectional view of (A). FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. It is an important section plane sectional view of a 3rd embodiment. FIG. 8 is a sectional view taken along the line VIII-VIII in FIG. 7. It is a principal part plane sectional view of a 4th embodiment.

(1). First Embodiment Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows an outline of an internal combustion engine. In the following description, the terms “front / rear”, “left / right”, and “up / down” are used to specify the direction, but the front / rear direction is the crank axis direction, and the left / right direction is the direction orthogonal to the crank axis and cylinder bore axis. The direction is the cylinder bore axis direction. As a precaution, the front-rear and left-right directions are clearly shown in FIG. In the case of FIG. 1A, the vertical direction is a direction perpendicular to the paper surface.

  The internal combustion engine has a cylinder block (not shown) having a cylinder bore 1 and a cylinder head 2 fixed to the upper surface of the cylinder block as components of the engine body. The internal combustion engine of the present embodiment has three cylinders, and three cylinder bores 1 are arranged in the direction of the crank axis 3 (front-rear direction).

  The intake air distribution device 4 is fixed to the intake side surface 2 a of the cylinder head 2, while the exhaust manifold 5 is fixed to the exhaust side surface 2 a, and the exhaust turbocharger 6 is fixed to the collecting portion of the exhaust manifold 5. Thus, the catalyst case 7 is arranged on the downstream side of the exhaust turbocharger 6. The internal combustion engine of this embodiment also has an EGR device, and the upstream end of the EGR pipe 8 is connected to an appropriate part such as the upstream side or the downstream side of the catalyst case 7.

  The intake air distribution device 4 includes an intercooler 11 and an intake manifold 12 that are arranged side by side on the left and right. Both are made of resin, but aluminum can also be used. The intake manifold 12 forms a spacer, and is interposed between the intercooler 11 and the cylinder head 2. In the intake manifold 12, three pairs of intake holes 14 are formed corresponding to the intake ports 13 of the cylinder head 2. As can be easily understood from the arrows in FIG. 2, the intercooler 11 and the intake manifold 12 are fastened to the cylinder head 2 by bolts (stud bolts) and nuts.

  The intercooler 11 is provided with a rectangular case (housing), in which a large number of cooling fins (cooling plates) 15 through which cooling water passes are opened with a certain amount of air gaps 16 above and below them. They are stacked in multiple stages. That is, the cooling fins 15 and the ventilation gaps 16 are alternately arranged vertically. The group of cooling fins 15 constitute a cooling unit 17 that cools the intake air.

  Further, in the interior of the intercooler 11, the part opposite to the cylinder head 2 across the cooling unit 17 is an inlet space 18, and the cylinder head 2 side is an outlet space 19. As shown in FIG. 2, the outlet space 19 is partitioned into three front and rear chambers by a partition wall 19 a, and each chamber communicates with a pair of intake holes 14 in the intake manifold 12. A portion of the intercooler 11 that overlaps the intake manifold 12 is a wide portion 11 a that has a larger front-rear width than the cooling portion 17. An inlet port 17a and an outlet port 17b for the cooling water are provided at the front and rear end portions of the upper surface of the intercooler 11.

  In the intercooler 11, an intake inlet 20 for introducing intake air is opened downward at the front and rear intermediate portions of the upper end of the inlet space 18. Therefore, the intake air inlet 20 opens toward the direction in which the cooling fins 15 are arranged. A throttle valve (not shown) is fixed to the intake inlet 20. As can be understood from FIG. 1, the throttle valve and the exhaust turbocharger 6 are connected by a supercharging passage 21. An intake pipe 23 starting from an air cleaner 22 is connected to the entrance of the exhaust turbocharger 6. When the exhaust turbocharger 6 is not provided, the intake pipe 23 is connected to the throttle valve.

  An EGR distribution main passage 24 that is long in the front-rear direction is formed in the intake manifold 12. As shown in FIG. 4, the EGR distribution main passage 24 and each intake hole 14 communicate with each other through the distribution hole 25. A downstream end of the EGR pipe 8 is connected to the inlet port of the EGR distribution main passage 24. In FIG. 2, the surface of the intake manifold 12 that faces the cylinder head 2 is simply displayed in a flat state. However, actually, as shown in FIG. 4, the surface is uneven. Yes.

As shown in FIG. 1, the portion of the intake manifold 12 where the inlet port of the EGR distribution main passage 24 is provided protrudes outside the intercooler 11, and this protruding portion 12a.
Is provided with an EGR valve (not shown).

  In the above configuration, the intake air that has reached the intercooler 11 from the supercharging passage 21 flows downward from the intake inlet 20 toward the inlet space 18, and then enters the cooling unit 17 by changing the direction to the left-right direction. To go. In this way, by changing the direction to a right angle, the intake air that flows downward with straightness is diffused widely in the left-right direction. For this reason, it is possible to spread the intake air as evenly as possible over the entire opening of the cooling unit 17 and improve the cooling efficiency.

  Further, since the EGR gas is distributed to the intake holes 14 from the distribution passages 24 and 25 provided in the intake manifold 12, the combustion in each cylinder can be equalized. As a result, it is possible to contribute to the stable operation of the engine and the improvement of exhaust gas purification performance.

(2). Other Embodiments Next, other embodiments shown in FIG. In the second embodiment shown in FIGS. 5 to 7, a diffusion portion 27 for dispersing the intake air in the front-rear direction and the vertical direction is integrally formed in the inlet space 18 of the intercooler 11. The diffusing portion 27 has a mountain shape in a side view as viewed from the left-right direction, and the left-right thickness decreases toward the top. Therefore, the intake air can be guided so as to spread in the front-rear direction and the up-down direction, and the intake air can be evenly distributed over the entire opening surface of the cooling unit 17.

  Therefore, in this embodiment, since the intake air can be more evenly distributed with respect to the front surface of the cooling unit 17, the performance of the intercooler 11 can be fully drawn and the cooling efficiency can be further improved. In this embodiment, the diffusing portion 27 is integrally formed with the intercooler 11, but the diffusing portion 27 is manufactured as a separate member from the intercooler 11, and the intercooler 11 is manufactured by appropriate means such as welding or screwing. It is also possible to fix to.

  In the third embodiment shown in FIGS. 7 and 8, the EGR gas distribution pipe 28 is arranged in the outlet space 19. The EGR gas distribution pipe 28 has a horizontal posture that is long in the front-rear direction, and both ends thereof are held by the intercooler 11 so as not to be detached. Of the two ends of the EGR gas distribution pipe 28, at least the inlet 28a is exposed to the outside of the intercooler 11, and the downstream end of the EGR pipe 8 is connected to the inlet 28a.

  The EGR gas distribution pipe 28 is disposed at a position slightly higher than the group of the intake holes 14, and discharge holes 29 are formed corresponding to the intake holes 14. The discharge hole 29 opens obliquely downward so as to face the intake manifold 12. Accordingly, the EGR gas is guided to the intake holes 14 along the flow of intake air.

  More specifically, the EGR gas has a positive pressure and has straight advanceability and is ejected from the discharge hole 29 toward the intake hole 14, but the directionality of the EGR gas flow coincides with the direction of the intake air flow. The EGR gas flows from the specific discharge hole 29 to the specific intake hole 14, whereby an even distribution of the EGR gas can be realized. In this embodiment, the EGR gas distribution pipe 28 need only be inserted into the intercooler 11 and fixed, and thus the structure is simple.

  In addition, a phenomenon in which EGR gas is sucked out from the EGR gas distribution pipe 28 appears due to the negative pressure effect caused by the flow of intake air, so that the intake of EGR gas is also smooth. Therefore, it is possible to make the control response of the EGR gas excellent. Furthermore, even if condensed water accumulates inside the EGR gas distribution pipe 28, it can be quickly eliminated by the suction action by the intake air. Therefore, it is possible to prevent a problem that the condensed water accumulated is frozen and obstructs the passage of EGR gas.

  In FIG. 9, a left and right EGR passage 30 is formed at one end of the cylinder head 2, and the EGR gas distribution pipe 28 is fitted into the intake manifold 12. That is, the EGR gas distribution pipe 28 has a U-shape in plan view in which one end and the other end are inserted into the intake manifold 12, and the inlet 28 a at one end is fitted into the communication hole 31 provided in the intake manifold 12. Yes. In this example, the EGR valve 32 is provided on one end face of the intake manifold 12.

  The embodiment of the present invention has been described above, but the present invention can be embodied in various ways. For example, the cooling fins can be arranged in the front-rear direction. In this case, the intake inlet also opens in the front-rear direction. Alternatively, the cooling fins can be arranged in the left-right direction, and in this case, the intake inlet is opened in the left-right direction.

  The present invention can actually be embodied in an intake air distribution device for an internal combustion engine. Therefore, it can be used industrially.

2 Cylinder Head 2a Intake Side 4 Intake Distributor 5 Exhaust Manifold 9 EGR Passage with Built-in Cylinder Head 10 EGR Passage Exit 11 Intercooler 12 Intake Manifold 13 Cylinder Head Intake Port 14 Intake Hole 15 Cooling Fin 16 Ventilation Gap 17 Cooling Section 18 Inlet space 19 Outlet space 20 Inlet inlet 24 EGR distribution main passage 25 Distribution hole 27 Diffusion member 28 EGR gas distribution pipe

Claims (1)

An intercooler that cools the intake air, and an intake manifold that distributes the intake air cooled by the intercooler to each intake port of the cylinder head,
The intercooler includes a cooling unit in which ventilation gaps and cooling fins are alternately arranged, and an inlet space located on one side across the cooling unit is an outlet located on the other side across the cooling unit And the inlet space and the outlet space are in communication with the group of the ventilation gaps,
In the intercooler, an intake inlet for taking intake air into the inlet space is opened in the direction in which the ventilation gap and the cooling fin are arranged, while the outlet space communicates with the intake manifold,
An EGR gas distribution passage is provided in the intake manifold or the outlet space.
Intake distribution device for an internal combustion engine.

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