JPH0455228Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial field of application] This invention, for example, in a multi-cylinder internal combustion engine, is equipped with an on-off valve that opens and shuts off the communication between the volumes that communicate with each of the two cylinder groups. , relates to an intake path control device for an internal combustion engine that improves intake efficiency using inertial supercharging.

[Prior art]

Generally, this type of intake path control device has, for example, 6
The cylinder engine has the following configuration. In other words, two cylinder groups are formed by dividing the cylinders whose intake strokes are not consecutive into three groups, and the two volume parts provided independently for these two cylinder groups are each provided with two independent resonant passages. It is connected to the surge tank. Further, each of the volume parts is connected to each other by a communication passage, and the communication passage is provided with an on-off valve for controlling opening and closing of the communication passage.

As shown in FIG.
The opening/closing drive of No. 1 is performed by a step motor 105.

With this configuration, in a low speed region where the engine speed is below a predetermined value, by closing the on-off valve, the natural frequency of the intake system of each independent cylinder group resonates with the intake pressure pulsation in the engine's low speed region. In addition, in high-speed ranges where the engine speed exceeds a predetermined value, opening the on-off valve allows each volume part to communicate with each other, changing the natural frequency of the intake system, so that it resonates with the intake pressure pulsations in the engine high-speed range. Become. This is intended to achieve a good inertial supercharging effect over the entire speed range of the engine. (Refer to Japanese Utility Model Application Publication No. 178421/1983) [Problems to be solved by the invention] However, in such a conventional intake path control device, the valve body 101 of the on-off valve is connected to the communication path 10.
3, the gap between the valve body 101 and the inner wall of the communication passage 103 when the valve is closed must be managed to ensure the dimensional accuracy of the valve body 101 and the communication passage 103, as well as the mutual assembly accuracy. Furthermore, considering the need to prevent the valve body 101 from sticking due to oil or the like adhering to the valve body 101, it is difficult to make the gap small, and it is necessary to make it large in order to have a margin. As a result, even if the on-off valve is closed, a large amount of intake air leaks, and a sufficient inertial supercharging effect cannot be obtained in a low speed region, resulting in a decrease in intake efficiency.

This idea was created by focusing on these conventional problems, and it is possible to minimize the gap between the valve body and the inner wall of the communication passage, thereby preventing a drop in intake efficiency in low speed ranges. The purpose is to provide an air intake path control device.

[Means for solving problems]

In order to achieve the above object, this invention forms multiple cylinder groups by combining cylinders whose intake strokes are not consecutive, and connects the independently provided volume parts of each cylinder group to adjacent output shafts. a linear portion that is shifted in the direction to form a space at the outer end of the volume portion, and that connects the volume portions with each other, and is separated by a partition wall and has a distal end communicating with each volume portion; and a proximal end side of the straight portion. A U-shaped communication passage having a bent part connecting the two is provided, and the bent part of the U-shaped communication passage is aligned with the space, and at the bent part, substantially opposite sides in the flow direction of intake air in the communication passage are provided. an inner fitting part that is provided with an opening at each position, and that fits into the end of the partition wall on the center side of the bending part, and an inner wall outside the bending part opposite to the inner fitting part that extends a predetermined length along the bending part. a casing having an outer fitting portion that is fitted into the casing; a valve body that is rotatably provided within the casing and opens and closes the communication passage; and a valve body that operates to open and close the valve body depending on the operating state of the engine An on-off valve device integrated with a valve body driving means is configured to be able to be installed from the space.

〔Example〕

Hereinafter, one embodiment of this invention will be described in detail based on FIGS. 1 to 8.

Figures 1 and 2 show a V-type six-cylinder internal combustion engine, in which a first cylinder group 1 is a combination of three cylinders on the left side, a second cylinder group 3 is a combination of three cylinders on the right side, and a second cylinder group 3 is a combination of three cylinders on the right side. In this case, the intake strokes of the cylinders in each cylinder group 1 and 3 are not continuous.

The combustion chamber 5 of the first cylinder group 1 is connected to a first intake collector (volume part) 9 via an intake manifold 7, and similarly, the fuel chamber (not shown) of the second cylinder group 3 is connected via an intake manifold 11. and communicates with the second intake collector (volume section) 13. The first and second intake collectors 9 and 13 are arranged adjacent to each other and shifted in the direction of a crankshaft (not shown) that is an output shaft (extended in the vertical direction in FIG. 1). In the figure, there is a space 1 between the upper end of the first intake collector 9 and the upper end side of the second collector 13.
4 is formed. The first and second intake collectors 9, 13 communicate with a first resonance passage 15 on the lower side and a second resonance passage 17 on the upper side in FIG. It communicates with the surge tank 19 on the upstream side.

The upper parts of the first and second intake collectors 9 and 13 in FIG. A communication passage 25 is provided that allows communication with the second intake collector 13. This communication passage 25 has a substantially inverted U shape by providing a partition wall 27 from between the communication hole 21 and the communication hole 23 upward in FIG. Straight portion 25 communicating with each communication hole 21, 23
b, 25c, and a bent portion 25a that interconnects the proximal ends of the straight portions 25b, 25c and partially aligns with the space 14.

The bent portion 25a of the communication path 25 having such a shape
An on-off valve device 29 that controls opening and closing of the communication passage 25 is installed near the downstream end of the first intake collector 9 . As shown in FIG. 4, the on-off valve device 29 includes a valve casing 31, a valve body 33 housed in the casing 31, and a step motor serving as a valve body driving means for rotating the valve body 33 via a valve shaft 35. 37, which are integrated and can be installed from the space 14 outside the communication path 25.

The casing 31 is fitted into the communication passage 25 and has a cylindrical cup shape with its left side open in FIG. Further, the cylindrical circumferential portion of the valve casing 31 is provided with openings 39 and 4 on opposite sides in the flow direction of the intake air, as shown in FIG.
1 is formed, and the gap α between the valve body 33 and the inner wall 43 of the cylindrical circumferential portion remaining due to the formation of the openings 39 and 41
(shown in FIG. 4) is kept extremely small when the valve body 33 and valve casing 31 are assembled.

The smaller the openings 39 and 41 are, the better in order to maintain high rigidity of the valve casing 31, while the larger the openings are, the better in order to increase the intake air filling efficiency when the valve is opened. Therefore, in this embodiment, the cylindrical circumferential portion is formed into a short inner fitting portion 31a on the side of the partition wall 27, while a predetermined length is formed along the bent portion 25a on the inner wall side outside the bent portion 25a opposite to the inner fitting portion 31a. By forming the outer fitting part 31b which is extended and long, that is, by forming it in a fan shape centered near the tip of the partition wall 27, the passage cross-sectional area of the communication passage 25 does not decrease due to the provision of the valve casing 31. The rigidity of the valve casing 31 is also increased as much as possible.

In FIG. 8, the cross-sectional area of the gap α between the valve body 33 and the inner wall surface 43 of the cylindrical circumferential portion when the valve body 33 is closed is assumed to be circular, and the horizontal axis shows the diameter equivalent, and the vertical axis shows the passage area when the valve body 33 is closed. The ratio of the intake efficiency η _v1 when the gap α is completely absent, that is, the intake efficiency η _v when the valve body 33 is installed and the communication passage 25 is closed:
(η _v1 /η _v )×100%, and in this embodiment, considering the operability of the valve body 33 and the intake efficiency, the cross-sectional area of the gap α is equivalent to the cross-sectional area of a hole with a diameter of 10 mm. It is a thing.

Note that the passage cross-sectional area of the communication passage 25, excluding the valve stem, is
It is ^18cm2 . As a result, an intake efficiency of approximately 95% can be obtained compared to when the gap α is completely reduced to 0.

As shown in FIG. 4, an intermediate member 44 is fitted into the left open portion of the valve casing 31, and a motor casing 45 is attached to the left side of the intermediate member 44 by tightening the intermediate member 44 and bolts 46 together. When the bolt 46 is fastened, the on-off valve device 29 itself is attached to the intake collector section. A step motor (valve drive means) 37 is housed within the motor casing 45 and is operated in response to signals from a control unit (not shown) depending on the engine operating state. The step motor 37 rotates the valve body 33 via the valve shaft 35 to control opening and closing of the communication passage 25.

In such a configuration, the step motor 37
is activated upon receiving a valve open or valve close signal from the engine control unit, and the valve body 33 rotates within the operating angle θ range shown in FIG. 7 to control the opening and closing of the communication passage 25. In this figure, the solid line shows the valve body 33 in the closed position, and the broken line shows the valve open position.

The gap α between the valve body 33 and the cylindrical peripheral inner wall 43 when the valve body 33 is in the closed state can be adjusted in advance by manufacturing the valve body 33 and the valve casing 31 as an on-off valve device 29 that is integrated with the valve body 33 and the valve casing 31. When manufacturing the casing 31 and assembling each other, the casing 31 is kept as small as possible without making it unnecessarily large, taking into account the stickiness of the valve body 33 due to oil adhesion, and furthermore, the casing 31 is kept as small as possible without making it unnecessarily large. The gap α remains stable even when installed.
Therefore, the leakage of intake air from the gap α in the low engine speed region where the valve body 33 is closed is reduced compared to the conventional system, and inertial supercharging is effectively performed in this operating region, improving intake efficiency. .

In addition, the inner fitting part 31 of the valve casing 31
a fits into the end of the partition wall 27, and the outer fitting part 31b fits into the inner wall of the bent part 25a, and the fitting area is made sufficiently large without impairing the opening area of the communication path 25. Leakage of intake air from these fitting parts can be minimized, and the valve body 33
This prevents a decrease in intake efficiency when the valve is closed.

Furthermore, since the above-mentioned mating area is sufficient,
The supporting rigidity of the valve body 33 and the rigidity of the valve casing 31 are extremely high, so that the valve casing 31 does not tilt when the on-off valve device 29 is assembled.
3, step motor 37, etc. are integrated, it becomes possible to mount the device reliably, and the assembling work efficiency is improved.

Furthermore, since the on-off valve device 29 is arranged using the space 14 formed by mutually shifting the first and second intake collectors 9 and 13 in the crankshaft direction, the entire intake device can be made more compact. is achieved.

Note that a step motor 3 is used as the valve body driving means.
7 may be replaced with a negative pressure actuator or the like.

[Effects of the invention] As described above, according to this invention, openings are provided at substantially opposite positions on the side in the flow direction of intake air,
and a fitting portion consisting of a short inner fitting portion on the center side of the bending portion, and a long outer fitting portion extending a predetermined length along the bending portion on the inner wall side outside the bending portion opposite to the inner fitting portion. An on-off valve that integrates a casing, a valve body that is rotatably provided in the casing and opens and closes a communication passage, and a valve body driving means that operates the valve body to open and close the valve body according to the operating state of the engine. Since the device is arranged in such a way that the gap between the valve body and the casing can be made as small as possible, the area of the fitting part is sufficient, and leakage of intake air between the valve body and the casing and from the fitting part is minimized. This makes it possible to prevent a decrease in intake efficiency when the valve body is closed.

Furthermore, since the fitting area is large enough, the supporting rigidity of the valve body and the rigidity of the casing are extremely high, and the casing does not tilt when assembling the on-off valve device. Combined with the fact that the driving means is integrated, it is possible to install it securely, improving the ease of assembly.

In addition, the volume parts provided independently for each cylinder group are adjacent to each other and shifted in the direction of the output shaft to form a space at the end of the volume part, and the curved part is aligned with this space. Since the on-off valve device can be attached from the intake device, the entire intake device can be made more compact.

[Brief explanation of drawings]

Figures 1 to 8 relate to one embodiment of this invention; Figure 1 is a plan sectional view of a V-type six-cylinder internal combustion engine, Figure 2 is a partial longitudinal sectional view of the same, and Figure 3 is a partial longitudinal sectional view of a V-type six-cylinder internal combustion engine. Figure 4 is an enlarged sectional view of the main parts of the figure, Figure 4 is a - sectional view of Figure 1, Figure 5 is a front view of the on-off valve device, Figure 6 is
5 is a plan view of FIG. 5, FIG. 7 is a cross-sectional view of FIG. 5, and FIG. 8 is an explanatory diagram showing the relationship between the gap area between the valve body and the inner wall of the communication passage and the intake efficiency when the valve is closed. FIG. 9 is a sectional view showing how the on-off valve is installed in a conventional communication path. 1...First cylinder group, 3...Second cylinder group, 9...
First intake collector (volume part), 13... Second intake collector (volume part), 25... Communication path, 29...
Opening/closing valve device, 31... Valve casing, 33...
... Valve body, 37... Step motor (valve body driving means), 39, 41... Opening, 14... Space,
25a...Bent part, 25b, 25c...Straight part, 27...Partition wall, 31a...Inner fitting part, 31
b...Outside fitting part.

Claims (1)

[Scope of utility model registration request] A plurality of cylinder groups are formed by combining cylinders whose intake strokes are not continuous, and the volume parts provided independently for each cylinder group are adjacent to each other and shifted in the direction of the output shaft to create a space at the outer end of the volume part. A U-shaped connection that connects the volume parts with each other and has a straight part that is separated by a partition wall and whose distal end communicates with each volume part, and a curved part that connects the base end of the straight part. A passage is provided, a bent part of the U-shaped communicating passage is aligned with the space, and openings are provided at substantially opposite positions in the intake air flow direction in the communicating passage at the bent part, and the bent part A casing having an inner fitting part that fits into the end of the partition wall on the center side, and an outer fitting part that extends a predetermined length along the bending part and fits into the inner wall outside the bending part opposite to the inner fitting part. and an on-off valve that integrates a valve body that is rotatably provided in the casing and opens and closes the communication passage, and a valve body driving means that operates to open and close the valve body according to the operating state of the engine. An intake path control device for an internal combustion engine, characterized in that the device is installed in the space.