JP2006177222A - Intake collector for v-shape internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an intake collector suitable for an internal combustion engine controlling intake air quantity by variable control of valve lift characteristics of an intake valve and to reduce ventilation resistance. <P>SOLUTION: The intake collector for a V-shape 6-cylinder internal combustion engine is constructed in a flat disk shape by a collector body 1 and a collector cover, and includes an annular flow passage composed of a first collector part 4, a communication passage 6, a second collector 5 in an outer peripheral portion. Intake air main flow flowing-in from an intake air inlet 8 provided in a tangential direction turns in the annular flow passage and is introduced to each cylinder from each collector part 4, 5 via branch parts 11 to 16 at an inner circumference part .Open ends of the branch parts 11 to 16 get in right front of the intake air main flow as the cylinder goes to more downstream side of the intake air main flow. Since intake air main flow does not branch to two collector part in the intake collector as conventional one, ventilation resistance is reduced. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention is suitable for an intake collector of a V-type internal combustion engine, and more particularly, an intake air suitable for a V-type internal combustion engine in which the amount of intake air is controlled by variably controlling the valve lift characteristics of the intake valve using a variable valve mechanism. Regarding the collector.

  For example, Patent Document 1 discloses an example of an intake collector of a V-type 6-cylinder internal combustion engine. In this intake collector, a pair of collector portions are provided in a central portion that is located between V banks of the internal combustion engine. The intake air is diverted from the throttle chamber behind the engine to each collector part, and the intake air flows from each collector part to each cylinder of the left and right banks.

Further, Patent Document 2 discloses an example of an intake control device that controls the intake air amount of an internal combustion engine and thus the load by variably controlling the valve lift characteristic of the intake valve without depending on the throttle valve. ing.
JP-A-8-105360 JP 2002-256905 A

  The above-mentioned patent document 1 is based on the premise that the intake air amount is controlled by a throttle valve. From the viewpoint of responsiveness to changes in throttle valve opening and distribution to each cylinder, as described above, The intake air is divided into two collector sections in parallel downstream of the throttle chamber disposed in the section. Therefore, a layout in which the intake duct toward the throttle chamber bends with a small radius of curvature tends to occur, and coupled with the diversion to the two collector parts, the pressure loss in the intake collector is large.

  In the load control based on the valve lift characteristic disclosed in Patent Document 2 and the like, the intake air amount is adjusted by changing the valve lift characteristic in accordance with the change in the accelerator opening, so that the response at the intake collector etc. upstream of the intake valve There is no problem with the distribution and cylinder distribution.

  Therefore, an object of the present invention is to provide an intake collector suitable for a V-type internal combustion engine that controls the intake air amount by such variable control of valve lift characteristics.

  The present invention includes a variable valve mechanism that can continuously change the valve lift characteristic of the intake valve as in claim 1 and controls the valve lift characteristic in accordance with engine operating conditions to thereby perform intake of the internal combustion engine. An intake collector of a V-type internal combustion engine that controls the amount of air, wherein the intake collector includes first and second left and right sides, respectively, so as to form an annular flow path in which an intake main flow swirls along an outer peripheral portion. In addition to the second collector portion, one end portions of the two are integrally connected by a communication passage, and an intake inlet is provided at the other end portion of the first collector portion along the swirling direction of the intake main flow. An intake outlet of each cylinder connected to the cylinder heads of the left and right banks via the lower manifold is disposed at the center of the bottom surface of the intake collector. Then, from the intake outlet, a plurality of cylinders in one bank are distributed to the first collector portion, and the cylinders in the other bank are directed to the second collector portion, and each tip opens toward each collector portion. The plurality of branch portions are arranged on the inner peripheral side of the annular flow path.

  Therefore, in this configuration, the main flow of the intake air flowing into the intake collector from the intake inlet flows in the order of the first collector portion, the communication path, and the second collector portion along the outer peripheral portion of the intake collector. Then, it flows from the first collector portion to each cylinder of one bank, and flows from the second collector portion to each cylinder of the other bank. Therefore, the intake mainstream does not branch to the two collector portions, and no airflow resistance is caused by the branch.

  In one desirable mode of the present invention, the angle of the open end of the branch portion of each cylinder with respect to the main intake air flowing through the outer peripheral portion is different for each cylinder. As described above, the intake main flow sequentially flows through the two collector portions, so that the passage lengths of the cylinders are relatively different, and as it is, the intake amount tends to decrease toward the downstream side of the intake main flow. On the other hand, the influence of the passage length can be offset by appropriately setting the degree of confrontation of the open end of the branch part with respect to the main intake air flow. In general, the downstream cylinder is configured to open to the intake mainstream.

  For the same reason, in a desirable one aspect of the present invention, the substantial channel cross-sectional area of the annular channel composed of the first collector part, the communication path, and the second collector part is downstream from the intake inlet. It is configured to gradually shrink as it goes. With this configuration, it is possible to suppress a decrease in the flow velocity on the downstream side of the main intake air flow, and to equalize the intake air amount of each cylinder.

  In one aspect of the present invention, the first collector portion, the communication path, and the second collector portion that form an annular flow path are continuous in a substantially U shape. In another aspect, the other end of the second collector portion which is the most downstream of the intake main flow is the other end of the first collector portion so that the annular flow path is continuous with the entire circumference of the intake collector. It communicates with the department.

  In a specific aspect of the present invention, the intake collector includes a flat collector body with an upper surface opening having a plurality of branch portions on an inner peripheral portion, and a collector cover that covers the upper surface opening of the collector body. Is done. In this case, the inside of the collector body covered with the collector cover becomes one space, and the first and second collector parts communicate with each other through the space around the branch part. This greatly simplifies the configuration.

  Preferably, the collector cover includes a reinforcing rib whose tip abuts on the collector body side at an inner peripheral portion that does not overlap the annular flow path. By arranging the reinforcing ribs in this way, the flat intake collector can be reinforced, and the main intake air flowing through the annular channel on the outer peripheral portion is not hindered.

  According to the present invention, since the main intake air flowing in from the intake inlet flows through the two collector portions in order without branching to the two collector portions, the ventilation resistance is reduced and the output of the engine can be improved.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

  1 to 5 show an embodiment in which the present invention is applied to an intake collector of a V-type 6-cylinder internal combustion engine. The internal combustion engine in which this intake collector is used is, for example, a first one that simultaneously and continuously enlarges / reduces the lift / operating angle of the intake valve, similar to the intake device disclosed in Patent Document 2 described above. A variable valve mechanism comprising a combination of a variable valve mechanism and a second variable valve mechanism that continuously delays the central angle of the operating angle is provided, and a combination of lift / operating angle and central angle is provided. The intake air amount is controlled by the variable control of the valve lift characteristic of the intake valve realized by the above. In addition, instead of a general throttle valve, a negative pressure generating valve having the same form as an electronically controlled throttle valve may be provided for the purpose of generating a slight negative pressure for blowby gas processing or the like. .

  The intake collector of this embodiment is disposed above the banks of the left and right banks. As shown in FIGS. 1 and 2, the collector body 1 having a flat upper surface opening and the upper surface of the collector body 1 are provided. The plate-shaped collector cover 2 that covers the opening is generally configured. The collector body 1 and the collector cover 2 are both made of synthetic resin, and the outer peripheral flange portions are joined to each other by appropriate means such as a plurality of bolts and an adhesive (not shown), and It is sealed.

  FIG. 5 shows only the collector body 1 from which the collector cover 2 has been removed. The collector body 1 has a generally circular shape on the plan view, and has an inner periphery of the # 1 cylinder to the # 6 cylinder. Six branch portions 11 to 16 corresponding to each other are arranged. A first collector portion 4, a second collector portion 5, and a communication passage 6 that connects one end portions of the branch portions 11 to 16 to each other are provided so as to surround the outer peripheral sides of the branch portions 11 to 16. An annular flow path through which the main flow flows is configured. An intake inlet 8 having a mounting flange 7 is provided on the other end of the first collector portion 4, that is, on the side opposite to the communication path 6, and the intake inlet 8 guides intake air along the tangential direction of the annular flow path. Thus, the direction is set, and the portion immediately downstream of the intake inlet 8 is a linear introduction path 9 that also serves as a part of the first collector portion 4. Further, in this embodiment, the end 5a of the second collector part 5 and the end 4a of the first collector part 4 on the opposite side of the communication path 6 are narrower in the cross-sectional area than the communication path 6. Communicating with each other without being blocked. Accordingly, the main intake air flow that flows from the intake inlet 8 follows the outer periphery of the intake collector in the order of the first collector portion 4, the communication path 6, and the second collector portion 5, as indicated by arrows S1 and S2 in FIG. And the flow returns from the second collector unit 5 to the first collector unit 4. That is, it turns along the outer periphery over the entire circumference.

  Here, as shown in FIGS. 3 and 4, the intake collector has its vertical thickness dimension gradually changed in the cylinder row direction, and is the highest on the # 1 cylinder side which is the front of the vehicle when mounted on the vehicle. Narrow and widest up and down on the # 6 cylinder side at the rear of the vehicle. The communication path 6 is on the # 6 cylinder side.

  In the central portion of the bottom surface of the collector body 1, six intake outlets 18 are arranged in a line so as to protrude downward in a cylindrical shape. These intake outlets 18 are connected to the intake ports of the cylinder heads of the left and right banks via a lower manifold (not shown).

  The branch portions 11 to 16 connect the intake outlet 18 arranged in the center of the collector body 1 to the left and right first and second collector portions 4 and 5, and as shown in FIGS. The branch portions 11, 13, and 15 for the # 1, # 3, and # 5 cylinders of the banks of the banks extend from the intake outlet 18 along the bottom of the collector body 1 while curving toward the second collector portion 5 and respectively. Tips 11 a, 13 a, and 15 a are open toward the second collector portion 5. Similarly, the branch portions 12, 14, and 16 for the # 2, # 4, and # 6 cylinders of the other bank are curved toward the first collector portion 4 from the intake outlet 18 along the bottom of the collector body 1. Each tip 12 a, 14 a, 16 a extends and opens toward the first collector portion 4. That is, in this embodiment, the six branch portions 11 to 16 are alternately distributed to the left and right. Note that, in relation to a cylinder head (not shown), each of the branch portions 11 to 16 has a so-called turn flow type structure that flows so as to make a U-turn, and a cylinder in a bank located below the first collector portion 4. Are connected to the first collector portion 4 side and the cylinders of the banks located below the second collector portion 5 are connected to the second collector portion 5 side, respectively, but the present invention is not limited to this, and one collector A so-called cross-flow type configuration in which the cylinders in the bank located below the part communicate with the collector part on the opposite side may be employed.

  Even when the collector cover 2 is attached, a slight gap remains above the branch portions 11 to 16 of the collector body 1 and is not particularly sealed from the collector cover 2. Therefore, the first collector part 4 and the second collector part 5 are actually connected integrally as one space, and there is no clear boundary between the collector parts 4 and 5. In other words, there are six branch portions 11 to 16 in the center portion of one flat space composed of the collector body 1 and the collector cover 2, and the remaining portion of the outer periphery thereof is an annular flow path (that is, the first flow path). The collector part 4, the second collector part 5, and the communication path 6) are provided. However, since the intake main flow tends to swivel around the outer periphery of the intake collector by centrifugal force, there is almost no flow crossing the space above the branch portions 11 to 16.

  The six branch portions 11 to 16 basically extend along the direction orthogonal to the cylinder row from the intake port 18 in the central portion, but each specific shape is different. The angles of the open ends 11a to 16a of the branch portions 11 to 16 with respect to the intake main flow are set in consideration of the inter-cylinder distribution performance. Specifically, the # 2-cylinder branch portion 12 and the # 4-cylinder branch portion 14 close to the intake inlet 8 are opened substantially orthogonal to the intake main flow direction of the first collector portion 4. On the other hand, the # 1 cylinder branch portion 11 which is the most downstream of the intake main flow faces the intake main flow direction of the second collector portion 5 at an angle close to the front. Then, in order of the intake main flow, the # 6 cylinder branch unit 16, the # 5 cylinder branch unit 15, and the # 3 cylinder branch unit 13 gradually approach the front from a state orthogonal to the intake main flow. The direction is different. With this configuration, variations in the intake air amount for each cylinder between the upstream side and the downstream side of the intake main flow are suppressed.

  For the same reason, the annular flow path formed in the outer peripheral parts of the six branch parts 11 to 16 has a substantial flow path cross-sectional area from the upstream side (near the intake inlet 8) to the downstream side (first). 2 It is desirable to gradually decrease toward the end portion 5a) of the collector portion 5. In this way, the flow velocity of the intake main flow in the annular flow path becomes more constant.

  In forming the collector body 1, the whole including the branch portions 11 to 16 may be integrally formed using a core, or the branch portions 11 to 16 may be formed in order to avoid complication of molding. The upper surface portion may be formed as a separate component from the bottom wall portion of the collector body 1, and these two components may be integrated by welding or bonding.

  On the other hand, the collector cover 2 having a thin plate shape is provided with four embossed reinforcing ribs 21 in order to increase its rigidity. These reinforcing ribs 21 are positioned so as not to overlap the annular flow path (the first collector part 4, the second collector part 5, and the communication path 6) so as not to hinder the main intake air flow swirling around the outer periphery, that is, the intake collector. Located on the inner periphery. Specifically, they are respectively arranged between the branch portions 11 to 16 that are arranged three by one on each side. These reinforcing ribs 21 have an elongated shape along the direction of the adjacent branch portions 11 to 16 and function as guide vanes for guiding the flow of intake air from the main intake air flow toward the branch portions 11 to 16. The reinforcing rib 21 comes into contact with the bottom portion on the collector body 1 side, more specifically, the boss portion 22 (see FIG. 5) that is slightly raised upward.

  In the above configuration, as described above, the intake air introduced into the intake inlet 8 via the intake duct (not shown) swirls in the annular flow path on the outer peripheral portion of the intake collector by centrifugal force, and each collector portion 4 and 5 are introduced into the branch portions 11 to 16 of the respective cylinders. Since the intake air amount is controlled by the intake valve downstream of the intake port, the inside of the intake collector is always maintained at almost atmospheric pressure (even if the above-described negative pressure control valve is provided). It is not necessary to consider the response of the pressure change to the accelerator opening change. Accordingly, since the main intake air does not branch into two collector portions in the intake collector, the ventilation resistance is small, which is advantageous in improving the output. Further, in the above configuration, the intake inlet 8 is provided in a tangential direction at the side of the disk-shaped intake collector, so that, for example, a V-type 6-cylinder internal combustion engine is mounted in a so-called vertical configuration in the engine room at the front of the vehicle. In this case, the intake duct can be laid out in a straight line from the air cleaner located at the front end of the vehicle body to the intake inlet 8, and the airflow resistance is minimized also from this point.

  Next, FIG. 6 schematically shows a second embodiment of the intake collector according to the present invention. In this embodiment, the first collector portion 4 and the second collector portion 5 are connected by the communication path 6, and an annular flow path is configured in a substantially U shape. That is, in this embodiment, the other end portion of the second collector portion 5 which is the most downstream of the annular flow path is not continuous with the other end portion of the first collector portion 4, and the intake main flow flowing from the intake inlet 8 As shown by the arrow S, the first collector part 4, the communication path 6, and the second collector part 5 turn in this order, but do not turn over the entire circumference. The structure of the branch parts 11-16 of an inner peripheral part is the same as that of the Example mentioned above.

1 is a perspective view of an intake collector according to the present invention. The disassembled perspective view of a collector body and a collector cover. The side view of this intake collector. Sectional drawing along the AA line of FIG. 5 of this intake collector. The top view which shows only a collector body. The top view which shows the 2nd Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Collector body 2 ... Collector cover 4 ... 1st collector part 5 ... 2nd collector part 6 ... Communication path 8 ... Intake inlet 11-16 ... Branch part 18 ... Intake outlet 21 ... Reinforcement rib

Claims (6)

A V-type internal combustion engine having a variable valve mechanism capable of continuously changing the valve lift characteristic of the intake valve, and controlling the valve lift characteristic according to engine operating conditions to control the intake air amount of the internal combustion engine An intake collector for the engine,
The intake collector is provided with first and second collector portions on both the left and right sides so as to form an annular flow path in which the intake main flow swirls along the outer peripheral portion, and one end of both is integrally connected by a communication path And the other end of the first collector part is provided with an intake inlet along the swirling direction of the intake mainstream,
In the central portion of the bottom surface of the intake collector, an intake outlet of each cylinder connected to the cylinder heads of the left and right banks via the lower manifold is disposed.
From the intake outlet, a plurality of branches are distributed so that the cylinders of one bank are directed to the first collector part, the cylinders of the other bank are directed to the second collector part, and the tips are opened toward the respective collector parts. And an intake collector for a V-type internal combustion engine, wherein the plurality of branch portions are disposed on an inner peripheral side of the annular flow path.   2. The intake collector of a V-type internal combustion engine according to claim 1, wherein an angle of an opening end of a branch portion of each cylinder with respect to an intake main flow flowing through the outer peripheral portion is different for each cylinder.   The substantial flow path cross-sectional area of the annular flow path composed of the first collector section, the communication path, and the second collector section is gradually reduced from the intake inlet toward the downstream. An intake collector for the V-type internal combustion engine according to 1.   The other end portion of the second collector portion, which is the most downstream of the intake main flow, communicates with the other end portion of the first collector portion so that the annular flow path is continuous with the entire circumference of the intake collector. An intake collector for a V-type internal combustion engine according to any one of claims 1 to 3.   The intake collector includes a flat collector body having an upper surface opening having a plurality of branch portions on an inner peripheral portion, and a collector cover that covers the upper surface opening of the collector body, and the first and second collector portions are The intake collector of a V-type internal combustion engine according to any one of claims 1 to 4, wherein the intake collector is in communication with each other by a space around the branch portion. The intake collector for a V-type internal combustion engine according to claim 5, wherein the collector cover includes a reinforcing rib whose tip is in contact with the collector body side at an inner peripheral portion that does not overlap the annular flow path.

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