JPH11294172A - Variable intake system of v-type internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the output in a high-speed region where a communicating port is open. SOLUTION: The inside of a collector 11 is partitioned into a pair of upper and lower volumetric chambers 13, 14, and branch parts 8 of the respective banks are connected thereto. The partition wall is provided with a pair of rectangular communication ports 21, 22, and the respective ports are opened or closed by open/close valves 23, 24. In the open/close valves 23, 24, each one end of valve element 23a or 24a is fixed to a common valve shaft 25, and is opened toward the base plate 18 with the turning of the valve shaft 25. In the open position, the valve elements 23a, 24a are fitted inside a recessed part 29 along the inside wall surface of the base plate 18, so that they are not projected inside the volumetric chamber 13. Then, the ventilation resistance is not caused, and a sufficiently large open area can be secured to enhance the output in a high-speed region.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intake device for a V-type internal combustion engine, and more particularly, to an independent volume chamber for each bank.
Also, the present invention relates to an improvement of a variable intake device that can switch between two separated chambers and a communication state according to engine operating conditions.

[0002]

2. Description of the Related Art For example, in a V-type six-cylinder internal combustion engine,
Since the intake strokes of the # 1, # 3, and # 5 cylinders of one bank and the # 2, # 4, and # 6 cylinders of the other bank do not overlap with each other, the intake systems of both banks are separated to reduce the intake stroke. A large intake dynamic effect can be obtained in the medium speed range. In the high-speed, high-load region, the left and right bank volume chambers are communicated with each other so as to shorten the substantial intake pipe length.
It is known that the filling efficiency is improved.

[0003] Therefore, for example, Japanese Patent Application Laid-Open No. 7-324658.
As described in Japanese Unexamined Patent Publication (Kokai) Publication No. H07-214, the interior of the collector is partitioned into a pair of volume chambers by partition walls, and each volume chamber is connected to each of the intake ports of the left and right banks,
Conventionally, various variable intake devices have been proposed in which a communication port is formed in a partition wall between the two chambers so that the communication port can be opened and closed by an on-off valve. Specifically, in the device described in the above publication, the inside of the collector in the shape of an elongated box is divided into upper and lower volume chambers by a partition wall at the center, and three branches are provided on one side surface of the collector. And a communication port is formed at one end of the partition wall, and a butterfly valve type opening / closing valve is provided here. The on-off valve closes the communication port in a low-to-medium-speed region of the engine, and opens in a high-speed region to communicate the volume chambers of each bank with each other.

[0004]

In the conventional structure as described above, the valve body of the on-off valve is located substantially along the wall surface of the partition wall in the closed state. Nevertheless, in the open state, since it is located away from the partition wall and intersects the partition wall at an angle of, for example, about 90 °, a large ventilation resistance is generated in the collector. In particular, in the high-speed range where the on-off valve opens, the flow rate of intake air is large, and the intake air flows at high speed in the collector.If the on-off valve rises in the middle part of the collector, the ventilation resistance becomes even greater and the high-speed range In this case, there is a problem that the output is reduced.

In addition, since the valve body tends to have a ventilation resistance in the open position as described above, it is difficult to arrange the on-off valve near the branch opening in the collector. For example, in the device described in the above publication, the on-off valve is disposed at the end of the collector, and the distance from the opening of the branch portion of each cylinder, particularly the opening of the cylinder located at the end on the opposite side of the collector, is reduced. The communication effect at the time of opening decreases accordingly. In other words, from the viewpoint of engine performance when the communication port is open,
It is desirable that the position of the communication port is located at the center of the collector and near the branch opening, but if the communication port is provided at such a position, the valve body of the on-off valve becomes a ventilation resistance,
This leads to a further large decrease in output. Similarly, since the valve body tends to have ventilation resistance at the open position, the size of the valve body of the on-off valve is restricted, and it is difficult to sufficiently secure the opening area of the communication port. Therefore, an optimal intake dynamic effect cannot be obtained at a high speed, and the output in a high speed region cannot be sufficiently increased.

[0006]

SUMMARY OF THE INVENTION Therefore, according to the present invention, the inside of the collector is divided into two volume chambers by partition walls, and the branch portions of each bank are connected to each volume chamber, respectively. In a variable intake device for a V-type internal combustion engine, a communication port communicating with the volume chamber is formed with an opening, and an opening and closing valve for opening and closing the communication port according to engine operating conditions is provided. Is provided with a valve shaft at one end thereof, and is configured to rotate around the valve shaft and to be in a state of being close to the inside of the collector along the inner wall surface of the collector at an open position where the communication port is opened. It is characterized by:

[0007] The open / close valve is controlled to be closed in a low to medium speed range, and closes the communication port. As a result, the intake system of each bank is separated and independent, and the torque is improved by the intake dynamic effect in the low to medium speed range. In the high-speed range, the communication port is opened, and the two volume chambers are in a communication state. As a result, the volume efficiency in the high speed range is improved.

Here, in the above configuration, the valve body is mounted on the valve shaft in a so-called cantilever manner.
This valve element is in a state of being close to the inner wall surface along the inner wall surface of the collector.

In other words, the valve element is in a state close to a state in which the valve element is attached to the inner wall surface of the collector. Therefore, the flow resistance of the valve body against the intake air flowing through the collector toward the branch opening becomes very small, and the output does not decrease in the high-speed region.

A second aspect of the present invention, which further embodies the first aspect of the present invention, is characterized in that the valve body is close to the same inner wall surface as the inner wall surface of the collector where the intake port opens.

[0011] Intake air enters the collector through an intake inlet opening on one inner wall surface, and flows out to the opening of each branch. That is, it flows mainly from the intake port to the branch opening in the collector. Therefore, if the valve element approaches the inner wall surface on the intake inlet side when the on-off valve is opened, the main flow of the intake air does not collide with the valve element, and the ventilation resistance is further reduced.

Further, the invention according to claim 3 is characterized in that a pair of the communication port and the on-off valve are provided, and the intake port is disposed at an intermediate portion between the pair of on-off valves.

According to the fourth aspect of the present invention, a pair of valve bodies are attached to the same valve shaft arranged along the partition wall.

By providing a pair of communication ports in this manner, a very large total opening area when opened is ensured.

Further, in the invention according to claim 5, the openings of the plurality of branches are arranged side by side in the longitudinal direction of the volume chamber, so that the openings do not project in the longitudinal direction of the volume chamber from the openings at both ends. , The communication port is disposed.

That is, the communication port is provided at a position relatively close to the opening of each branch and near the center of the collector. As a result, the pressure in the communicating state is more reliably balanced, and the output in the high-speed range is improved.

In the invention according to claim 6, a concave portion in which the valve element is fitted is formed on the inner wall surface of the collector where the valve element approaches. Therefore, when the valve element is opened, the valve element enters the concave portion of the inner wall surface of the collector, so that the ventilation resistance is further reduced.

[0018]

According to the variable intake device for a V-type internal combustion engine according to the present invention, when the on-off valve opens the communication port, the valve element of the on-off valve does not protrude into the collector, so that ventilation resistance is obtained. Therefore, it is possible to avoid a decrease in output in a high-speed region due to the airflow resistance. Further, the degree of freedom of the formation position and the opening area of the communication port is increased, and it is possible to secure a sufficiently large communication port near the opening of the branch portion, for example.

According to the second aspect of the present invention, since the valve element opens on the side that does not interfere with the main flow of intake air, the airflow resistance can be further reduced.

According to the third or fourth aspect of the present invention, the total opening area of the communication port can be further increased, which is more advantageous in the performance in a high speed range where the on-off valve opens.

Further, according to the sixth aspect of the present invention, the valve body is fitted in the recess, so that the airflow resistance is further reduced.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows the overall structure of a V-type six-cylinder internal combustion engine provided with a variable intake device according to the present invention. This internal combustion engine has 6 cylinders arranged in a V-shape on a cylinder block 1.
Each of the left and right banks has a cylinder head 4 mounted on each of the left and right banks. The cylinder head 4 has an intake port 5 on the side inside the bank and an exhaust port (not shown) on the outside of the bank. In the figure, 6 is an intake valve, and 7 is a fuel injection valve.

The intake port 5 is connected to one end of an independent branch portion 8 for each cylinder, and the other end of each branch portion 8 is connected to one side surface of a box-shaped collector 11. I have. The collector 11 is divided into a pair of upper and lower volume chambers 13 and 14 by a partition wall 12 provided in the center in a substantially horizontal direction. The three branch portions 8 of the bank on the left side of the figure are connected to the lower volume chamber 14. The branch portion 8 of the collector 11
The resonance pipes 15 and 16 which serve as intake passages connected to the respective volume chambers 13 and 14 are connected to the side surfaces on the opposite side from the above. The pair of resonance tubes 15 and 16 are gathered in a single passage on the upstream side, have a throttle valve 20 (see FIGS. 2 and 3) on the upstream side, and have an air flow meter and an air cleaner (not shown). Is arranged on the upstream side.

FIG. 2 and FIG. 3 show details of the collector 11. The collector 11 comprises a box-shaped body 17 having one side opened and a base plate 18 attached to the opening of the body 17. The body 17 is integrally formed with six branch portions 8. And the resonance tube 1 is mounted on the base plate 18.
5 and 16 are connected. These members are cast, for example, from an aluminum alloy or the like. Note that, as shown in FIG. 1, the downstream portion of each branch portion 8 may be configured as a separate member.

The partition wall 12 is formed integrally with the base plate 18 and abuts against the inner wall surface of the body 17 via a seal member 19 attached to a peripheral edge thereof. As shown in FIG. 3, the partition wall 12 has an elongated and substantially rectangular shape in a plan view.
At both ends, substantially rectangular communication ports 21 and 22 are formed respectively. In addition, as shown in FIG. 3, each of the communication ports 21 and 22 has an opening of the two branch portions 8 located at both ends of the six branch portions 8 connected to the upper and lower volume chambers 13 and 14. It is located at a position substantially corresponding to the portion 8a. In order to open and close the communication ports 21 and 22 according to the engine operating conditions, on-off valves 23 and 24 are provided respectively. The on-off valves 23 and 24 include a valve shaft 25 rotatably supported by the base plate 18 and a substantially rectangular plate-like valve body 23 a and 24 attached to the valve shaft 25.
a. That is, in this embodiment, the pair of on-off valves 23 and 2 are
4 are configured. Here, the valve shaft 25
Is the base of partition wall 12, that is, base plate 1
8 is arranged along the longitudinal direction of the partition wall 12 at a portion intersecting with the bottom wall of the valve shaft 25.
One end of each of the valve bodies 23a and 24a is fixed by a screw 26 so as to form a so-called cantilever. As shown in FIG. 4, a diaphragm type negative pressure actuator 27 on the side of the base plate 18 is linked to one end of the valve shaft 25. With the operation of the negative pressure actuator 27, the valve shaft 25 It is designed to make a strong 90 ° rotation. The valve bodies 23a and 24a rotate as shown in FIG. 2 with the rotation of the valve shaft 25, but close the communication ports 21 and 22 at a position along the partition wall 12 and separate from the partition wall 12. Base plate 18
The communication ports 21 and 22 are opened at a position along the side wall of. The opening edges of the communication ports 21 and 22 are provided with valve bodies 23a and 24, respectively.
At the closed position a, there are provided step portions 28 which come into contact with the peripheral edges of the valve bodies 23a and 24a. The side walls of the base plate 18 are provided with recesses 29 corresponding to the valve bodies 23a and 24a, respectively. When the valve bodies 23a and 24a rotate to the open position as shown in FIG. It fits in the recess 29.

The resonance tubes 15 and 16 are connected to the base plate 18 as described above.
The intake ports 30 and 31 to which the ports 5 and 16 are connected are located at the longitudinal center of the collector 11 between the pair of on-off valves 23 and 24. Specifically, as shown in FIG. 4, in the upper volume chamber 13, between the pair of recesses 29 corresponding to the valve bodies 23 a and 24 a, an oval-shaped intake inlet 30 is formed, and the lower volume is formed. In the chamber 14, the intake inlet 3 is formed so as to be symmetrical with the partition wall 12 therebetween.
1 is formed.

In the above configuration, the intake air flows from the pair of resonance tubes 15 and 16 to the respective volume chambers 13 and 1 in the collector 11.
4 and is supplied to each cylinder via each branch portion 8. In a low-to-medium speed range of the engine, for example, in a range of 4000 rpm or less, the pair of on-off valves 23 and 24 is controlled to be closed,
Both volume chambers 13 and 14 become independent. That is, the intake systems of the left and right banks are separated and independent, and the torque in the low and middle speed ranges is improved by the intake dynamic effect. In a high-speed region of the engine, for example, in a region of 4000 rpm or more, the pair of on-off valves 23 and 24 are controlled to open positions, and
3 and 14 are in a state of communicating with each other integrally through the communication ports 21 and 22. As a result, the pressures in the two chambers 13 and 14 become uniform, and the volume efficiency in the high-speed region is improved.

At this time, in the above configuration, the valve bodies 23a, 23
Reference numeral 4a denotes a state in which it adheres to the side wall surface of the base plate 18 in the collector 11, particularly a state in which it is fitted in the recess 29, and hardly projects into the volume chamber 13. Therefore, there is no airflow resistance to the intake airflow flowing in the collector 11. In particular, in the above configuration, since the valve bodies 23a and 24a open along the inner wall surfaces of the intake ports 30 and 31, the intake air flowing from the intake ports 30 and 31 toward the branch portion 8 and the valve bodies 23a and 24a Is more reliably avoided.

In the above embodiment, the communication ports 21 and 22
Are provided, and the total opening area thereof is sufficiently large, so that the pressure balancing action via the communication ports 21 and 22 is further improved. In particular, the distance from the opening 8a of each branch portion 8 to the communication ports 21 and 22 is very short, as compared with the case where the communication port is biased to one end as in the related art, and the valve bodies 23a and 24a The output in the high speed region is improved in combination with the reduction in the ventilation resistance.

FIG. 5 is a characteristic diagram showing the torque characteristics of the internal combustion engine using the intake device of the present embodiment in comparison with those of the conventional intake device. Torque reduction can be suppressed. In the illustrated example,
At 4000 rpm, the communication port is switched from closed to open.

[Brief description of the drawings]

FIG. 1 is a sectional view of an entire V-type internal combustion engine including an intake device according to the present invention.

FIG. 2 is an enlarged sectional view showing a collector portion.

FIG. 3 is a sectional view taken along the line AA of FIG. 2;

FIG. 4 is a sectional view taken along line BB of FIG. 2 showing only a base plate.

FIG. 5 is a characteristic diagram showing torque characteristics of an internal combustion engine provided with the intake device according to the present invention in comparison with the case of a conventional intake device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 8 ... Branch part 11 ... Collector 12 ... Partition wall 13,14 ... Volume chamber 21,22 ... Communication port 23,24 ... On-off valve 23a, 24a ... Valve 25 ... Valve shaft 29 ... Concave part 30,31 ... Suction inlet

Claims (6)

[Claims] 1. The interior of a collector is divided into two volume chambers by partition walls, branch portions of each bank are connected to each volume chamber, and a communication port for communicating both volume chambers to the partition wall is formed. And, in the variable intake device of the V-type internal combustion engine provided with an on-off valve for opening and closing the communication port according to the engine operating condition, the on-off valve has a valve shaft at one end of a plate-shaped valve body. A V-type internal combustion engine, characterized in that the valve body is configured to rotate around a valve shaft and to be in a state of being close to the inner wall surface of the collector at an open position where the communication port is opened. Variable intake device. 2. The variable intake device for a V-type internal combustion engine according to claim 1, wherein said valve element is located close to the same inner wall surface as the collector inner wall surface where the intake inlet is open. 3. The variable intake device for a V-type internal combustion engine according to claim 2, wherein the communication port and the on-off valve are provided in a pair, and the intake port is disposed at an intermediate portion between the pair of on-off valves. . 4. The variable intake device for a V-type internal combustion engine according to claim 3, wherein a pair of valve bodies are attached to the same valve shaft arranged along the partition wall. 5. The opening of a plurality of branches is arranged in the longitudinal direction of the volume chamber, and the communication port is arranged in a range not protruding in the longitudinal direction of the volume chamber from the openings at both ends thereof. The variable intake device for a V-type internal combustion engine according to any one of claims 1 to 4, wherein: 6. The inner wall surface of the collector in which the valve element is adjacent,
The variable intake device for a V-type internal combustion engine according to any one of claims 1 to 5, wherein a concave portion in which the valve body fits is formed.