JPH04350320A - Air intake device for engine - Google Patents

Abstract

PURPOSE:To suitably arrange air intake passages to miniaturize an engine by providing small sized collecting part for collecting independent intake passages of the same-length for respective cylinders, thereby effectively utilizing the dynamic effect of air intake over a wide range of engine speed by means of a relatively simple structure. CONSTITUTION:In a V type six-cylinder engine 1, the downstream ends of independent intake passages 7 of the same length are respectively connected to respective intake ports, and the upstream ends are collected and connected respectively to collectors 9f, 9r arranged above a bank Br at the rear as small- sized collecting parts for respective banks Bf, Br. The upstream ends of collecting passages 10f, 10r are collected and connected to a collecting part 11 on the upstream side. The center parts of the collectors 9f, 9r are connected to each other by an L-shaped connecting passage 12, and an opening and closing valve is installed to the connecting passage 12, depending on the engine speed. Thus, the dynamic effect of air intake is improved, and thereby the engine can be miniaturized.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intake system for a multi-cylinder engine, and more particularly to an intake system for an engine that has a plurality of cylinder rows and has a structure in which independent intake passages for each cylinder are gathered in a collection part for each cylinder row. Regarding.

0002

[Prior Art] Conventionally, in order to improve the output performance of an engine, various methods have been used to increase the filling efficiency of intake air.
Some systems supercharge intake air by utilizing dynamic effects such as the resonance effect or inertia effect of intake air. For example, Japanese Patent Application Laid-Open No. 101820/1982 has two cylinder rows, each cylinder row is provided with a chamber as an independent collecting section, and two long and short independent intake passages are provided in the chamber from each cylinder. At the same time, each of the above-mentioned chambers is arranged between the cylinder rows, and a communication passage is provided to communicate the chambers with each other, and an on-off valve for opening and closing each of the above-mentioned independent intake passages and the communication passage is provided, respectively. It is disclosed that the dynamic effect of intake air can be utilized over a wide engine speed range by appropriately opening and closing a valve.

[0003] Also, as an engine intake system, as disclosed in Japanese Utility Model Application Publication No. 60-88062, independent intake passages that communicate with each cylinder independently are bundled on the upstream side to form a small collective part. The independent intake passages are connected to have equal lengths and have equal lengths up to the resonance tuning point in the small gathering section, which improves the distribution of intake air to each cylinder and improves the dynamic effect on each cylinder. There are known devices designed to improve and make the quality uniform.

0004

[Problems to be Solved by the Invention] By the way, as described in the above-mentioned Japanese Patent Application Laid-Open No. 62-101820, in an engine having a plurality of cylinder rows,
When applying the equal-length independent intake passages as described in Publication No. 2, it is generally necessary to provide a small gathering section for each cylinder row because the number of cylinders increases. In this case, if a small collecting section for each cylinder row is arranged between the cylinder rows, each cylinder and the small collecting section become closer to each other, and the independent intake passage length for each cylinder becomes shorter. However, since it is necessary to ensure a predetermined intake flow rate in each cylinder, the passage diameter of the independent intake passage cannot be reduced, so if the length of the independent intake passage is shortened, the engine becomes a tuning point where intake resonance effect or inertia effect is obtained. The rotation speed range shifts to the high rotation side and may exceed the practical rotation speed range of general passenger car engines. Therefore, it is necessary to secure a certain length for the independent intake passage, but in the case where the small gathering section is arranged between the cylinder rows as described above, it is necessary to move the small gathering section upward due to the layout. Become,
There is a problem in that the overall height of the engine becomes high, making it impossible to make the engine more compact. On the other hand, if the small collecting section for each cylinder row is placed on one side of each cylinder row, the above problem will be solved, but the collecting passage, which is the intake passage upstream of the small collecting section, will be long due to the layout. This makes it difficult to make the intake system more compact, which in turn hinders making the engine more compact.

[0005] The present invention has been made in view of the above points, and an object of the present invention is to provide a small gathering section constituting independent intake passages of equal length in an intake system for an engine having a plurality of cylinder rows. The present invention aims to make the engine more compact by appropriately arranging the intake system passages while making it possible to effectively utilize the dynamic effect of intake air over a wide engine speed range with a relatively simple structure.

[0006]

[Means for Solving the Problem] In order to achieve the above object, the solving means taken by the invention of claim 1 has a plurality of cylinder rows, and each cylinder row communicates with each cylinder independently. The present invention is based on an engine intake system in which independent intake passages are grouped together to form a collection passage, and furthermore, the collection passages for each cylinder row are collected on the upstream side. Each of the independent intake passages is set to have the same length up to the resonance tuning point of the small-volume small collecting parts gathered in the collecting passage, and all of the small collecting parts are arranged on the side of one cylinder row. , a communication passage that communicates the centers of these small gathering parts with each other is provided, and the communication passage is provided with an on-off valve that is opened and closed according to the engine speed.

Furthermore, in the invention of claim 2, in the invention of claim 1, the engine is a V-shaped engine formed in a V-shape with two banks each having a cylinder row, and the crankshaft is connected to the vehicle body. Mounted horizontally across the vehicle width,
The small clusters from the cylinder rows of both banks are arranged on the rear bank side, with the small clusters of the cylinder rows of the rear bank on the bottom and the small clusters of the cylinder rows of the front bank on the top. They are arranged one above the other, and a communication path that communicates both the small gathering parts is formed in an L-shape.

In the invention of claim 3, in addition to the structure of the invention of claim 2, the vicinity of the connection part between the small collecting part of the cylinder row of the rear bank and the communication passage and the upstream part of the collecting passage are connected to the engine body. The structure supports this.

[0009]

[Operation] With the above configuration, in the invention of claim 1, each small gathering portion is arranged on the side of one cylinder row, so the overall height of the engine is suppressed while ensuring a certain length of each independent intake passage. Furthermore, since the collecting passages upstream of each of the small collecting parts are close to each other, the upstream intake passage does not become long, and the intake system passage is also made more compact, thereby effectively making the engine more compact. .

[0010] Furthermore, a communication passage is provided that communicates the centers of the small gathering parts with each other, and the communication passage is equipped with an on-off valve that opens and closes depending on the engine speed. By closing the above-mentioned on-off valve to prevent communication between the communication passages in the low and medium engine speed ranges, the intake air has a resonance effect in which the collection passage at the upstream end of the collection passage becomes a pressure reversal area and the collection passage becomes a resonant space. supercharged by On the other hand, in the high engine speed range, by opening the on-off valve and communicating the communication passage, the intake air is controlled by a resonance effect in which the opening of the small gathering part to the communication passage becomes a pressure reversal part and the communication passage becomes a resonance space. In addition, the intake air is also supercharged by an inertial effect using the opening to the communication passage as a pressure reversal part, so that effective supercharging is achieved by the dynamic effect of the intake air.

[0011] In the invention of claim 2, the engine is a V-type engine mounted transversely to the vehicle body, and each small collection part from the cylinder rows of both banks is arranged on the rear bank side, and the above-mentioned They are arranged vertically, with the small cluster of cylinders in the rear bank on the bottom and the small cluster of cylinders in the front bank on the top, so the dead space above the rear bank in the engine room is saved. Through effective use, the overall height of the engine can be suppressed along the bonnet line while ensuring a certain length of each independent intake passage. Furthermore, since the communication path that communicates the two small-sized gathering parts is formed in an L-shape, ease of assembly when connecting the communication path to both the small-sized gathering parts is improved.

Furthermore, in the invention as claimed in claim 3, since the vicinity of the connection between the small collecting part of the cylinder row of the rear bank and the communication passage and the upstream part of the collecting passage are supported on the engine body, the cylinder row of the front bank The small gathering part of the is supported via the communication passage, and if a heavy object such as a throttle body is installed at the connecting part that gathers into one common intake passage at the upstream part of the gathering passage, its weight will be reduced. It is possible to support objects without having to support them separately, and it is possible to reduce the number of supporting parts for the entire intake system passage.

[0013]

Embodiments Hereinafter, embodiments of the present invention will be explained based on the drawings.

FIGS. 1 and 2 show the overall structure of an engine intake system according to an embodiment of the present invention. Reference numeral 1 indicates a crankshaft (not shown) connected to the vehicle body in the vehicle width direction (vertical direction in FIG. 2). This engine 1 is a V-type six-cylinder engine mounted horizontally in a vehicle.The engine 1 has a pair of front banks Bf and rear banks Br that face each other in the longitudinal direction of the vehicle. The engine 1 includes a cylinder block 2 having a substantially V-shaped cross section, a pair of front and rear cylinder heads 3f, 3r assembled on the upper surface of the cylinder block 2, each cylinder head 3f,
Cylinder head cover 4f assembled on the top surface of 3r
, 4r. The front bank Bf has the second and fourth banks.
and the sixth three cylinders 52, 54, 56, and the rear bank Br has the first, third and fifth three cylinders 51,
53 and 55 are arranged and formed in series in the bank length direction, respectively. The rear side of the front cylinder head 3f (
Three intake ports 6, 6, . . . whose downstream ends communicate with the respective cylinders 52, 54, 56 of the front bank Bf are formed on the side surface of the side between the banks Bf and Br. On the other hand, similarly, the front side of the rear cylinder head 3r (the side between banks Bf and Br)
On the side, each cylinder 51, 53, 55 of the rear bank Br is shown.
Three intake ports 6, 6, .

[0015] The downstream ends of independent intake passages 7, 7, . Each of the independent intake passages 7 is assembled and connected to each other, and the pipe lengths of the independent intake passages 7 are equal to each other. Each of the collectors 9f and 9r has a collective passageway 10f.
, 10r are connected, and these collective passages 1
The upstream ends of Of and 10r are collected and connected to an upstream gathering portion 11. An intake manifold 8 is configured from each of the independent intake passages 7 to the upstream gathering portion 11. This intake manifold 8 is arranged above the engine 1 and between the engine 1 and the bonnet line L indicating the underside of the hood of the vehicle body, and the collectors 9f and 9r for each bank Bf and Br are both located in the rear bank Br. placed above. Specifically, the collector 9f of the front bank Bf is arranged above the front end of the cylinder head cover 4r of the rear bank Br, and the collector 9r of the rear bank Br is arranged above the rear end of the cylinder head cover 4r of the rear bank Br and on the front side. The collectors 9f and 9r are arranged at a lower height than the collector 9f, and the collectors 9f and 9r are vertically arranged with their centers located between the third cylinder 53 and the fifth cylinder 55 of the rear bank Br. There is.

Further, as shown in FIGS. 3 and 4, the intake manifold 8 is divided into two intake manifolds 8f and 8r, which are connected to the banks Bf and Br, respectively, and one is connected to the front bank Bf. As shown in FIG. 3, the intake manifold 8f has independent intake passages 7 connected to the intake ports 6 of each cylinder of the front bank Bf.
, 7, ... and a collector 9f that collects and connects the upstream ends of these independent intake passages 7, 7, ...,
Each of the independent intake passages 7 and the collector 9f are integrally connected. Here, integrally connected means a case where the parts are integrally formed by casting or the like, or are connected in a way that cannot be disassembled by welding or the like. At the downstream end of each independent intake passage 7, there is a mounting flange 7 for connection to each intake port 6.
f is formed, and the flange 7f is provided with mounting screw holes 7a, 7a, . . . . Collector 9 above
f is provided with a connecting portion 91 for connecting to the collective passage 10f, which is an intake passage on the upstream side thereof, and the connecting surface thereof is formed slightly toward the rear of the vehicle body than the rear side of the cylinder row. Further, the collector 9f is formed with a communication passage connecting portion 92 that is open to communicate with the center of the collector 9f and whose opening direction is directed toward the rear of the vehicle body.

On the other hand, the intake manifold 8r connected to the rear bank Br is connected to the rear bank Br as shown in FIG.
It is composed of independent intake passages 7, 7, . The independent intake passage 7 and the collector 9r are integrally connected. A collection passage 10r, which is an intake passage on the upstream side, is integrally connected to the collector 9r.Furthermore, the upstream end of this collection passage 10r is integrally connected to an upstream collection part 11, Side gathering part 1
1 is also integrally connected to the upstream end of the collective passage 10f of the front bank Bf. A mounting flange 7r is formed at the downstream end of each of the independent intake passages 7 for connection to each of the intake ports 6, and the flange 7r is provided with mounting screw holes 7b, 7b, . . . There is. A connecting portion 94 that is connected to the connecting portion 91 of the collector 9f of the front bank Bf is formed at the downstream end of the collecting passage 10f, corresponding to the connecting portion 91 of the collector 9f. At portions 91 and 94, the intake manifolds 8f and 8r are connected to each other. Collector 9 above
A communication path connecting portion 93 is formed in r, and is open to communicate with the central portion of the collector 9r, and the opening direction thereof is directed upward. Further, each independent intake passage 7 connected from the intake port 6 of each cylinder of the rear bank Br to the collector 9r is arranged so as to avoid over the plug hole 13 of each cylinder and pass above between each plug hole 13. is formed. That is, in FIG. 2, the first and third cylinders 5
The independent intake passages 7, 7 connected to the first cylinder 5
1 plug hole 13 and plug hole 1 of the third cylinder 53
The independent intake passage 7, which is connected to the fifth cylinder, passes above between the plug hole 13 of the third cylinder 53 and the plug hole 13 of the fifth cylinder 55, and is connected to the fifth cylinder. It is connected to the collector 9r.

Each end of the L-shaped communication path 12 is connected to the communication path connection portions 92, 93 of each of the collectors 9f, 9r, and the center portions of the collectors 9f, 9r are connected to each other. It is now possible to communicate. Above communication path 1
At the end of No. 2 on the side connected to the collector 9r, there is a communication path 1.
An on-off valve 14 for opening and closing the on-off valve 2 is provided, and the opening and closing operation of the on-off valve 14 is performed by a negative pressure actuator connected to the valve shaft of the on-off valve 14 via a rod. That is, the above-mentioned on-off valve 1
Valve 4 is closed in the low and medium engine speed range, and opened in the high engine speed range.

The collecting passages 10f and 10r are formed so as to extend from the respective collectors 9f and 9r toward the rear of the cylinder row, and then curve obliquely toward the front of the vehicle body. They are collected in a section 11 and connected to each other. A support portion 11a is formed at the lower part of the upstream gathering portion 11, and this support portion 11a is fixed to a mounting boss 31 provided at the rear end of the cylinder row of the rear cylinder head 3r. Collector 9r of the above rear bank Br
A support boss 93a is formed extending downward in the lower part near the communication passage connecting portion 93, and as shown in FIG. It is fixed to a formed mounting boss 32.

Therefore, in the above embodiment, each collector 9f, 9r collectively connects the independent intake passages 7, 7, . are both placed above the rear bank Br, so the dead space above the rear bank Br and the bonnet can be effectively used. By making the intake passages 7 follow the bonnet line L, the overall height of the engine can be suppressed and the engine can be made more compact while ensuring a certain length of each independent intake passage 7. Furthermore, the centers of both collectors 9f and 9r are connected to the rear bank B.
r Third cylinder 53 and fifth cylinder 55, which are approximately at the center in the longitudinal direction
Since the intake manifold 8 does not protrude beyond the main body of the engine 1 in the direction of the output shaft (bank longitudinal direction), the collectors 9f and 9r are close to each other and the upstream side of the intake manifold 8 is Side gathering passage 10f,
10r is not too long, and the engine 1 can be made more compact in the output shaft direction. At this time, each independent intake passage 7 and each collector 9f, 9r avoids being above the plug hole 13 for each cylinder of the rear bank Br, so that plug serviceability can be ensured.

The collector 9r of the rear bank Br also has a support boss 93a provided at the lower part near the center thereof.
Since it is supported by the cylinder head 3r on the side of the engine 1 main body via the bracket 15, it is possible to effectively support the part of the intake manifold 8r of the rear bank Br that is away from the side where it is attached to the engine 1. With,
The intake manifold 8f of the front bank Bf can also be supported via the communication passage 12. Furthermore, the upstream collecting section 11
is supported by the cylinder head 3r on the main body side of the engine 1 by the lower support part 11a, so if a heavy object such as a throttle body is connected to the upstream end of the upstream gathering part 11 or the intake passage immediately upstream, In addition, the above-mentioned heavy objects can be supported without additional support.

Since the communicating passage 12 is formed in an L-shape, it is possible to easily connect the communicating passage connecting portions 92, 93 of the respective collectors 9f, 9r, thereby improving the ease of assembly. In addition, it is possible to secure a straight section for arranging the on-off valve 14, and to connect the collectors 9f and 9r with the shortest length without reducing the cross-sectional area of the passage.
When the communication path 12 is used as a resonance space, the resonance tuning rotation speed can be shifted to the high rotation side. In this case, each of the collectors 9f and 9r has its center located at the rear bank B.
Since it is located between the third cylinder 53 and the fifth cylinder 55 of the V-type engine, the distance between the collectors 9f and 9r is the shortest, despite the offset of the cylinder rows for each bank Bf and Br due to the V-type engine. Therefore, the length of the communicating path 12 can be more effectively shortened.

[0023] Also, in the engine low and medium speed range, the on-off valve 1
4 is closed, the intake air is supercharged by a resonance effect in which the upstream collecting section 11 is used as a pressure reversal section and the collecting passages 10f and 10r are respectively resonant spaces. In addition, in the engine high speed range, the on-off valve 14 opens and the communication passage 1
2 is opened, so the intake air is from each collector 9.
Supercharging is achieved by a resonance effect in which the opening of the connecting portion between f, 9r and the communication passage 12 is used as a pressure reversal part, and the communication passage 12 is used as a resonance space. Furthermore, the intake air is also supercharged by an inertial effect using the opening as a pressure reversal section. In addition, since each of the independent intake passages 7 is set to have the same length as each other and is collected into collectors 9f and 9r, which are small collection parts,
The distribution of intake air to each cylinder can be improved, and the above-mentioned dynamic effect of intake air can be obtained without variation among the cylinders. For these reasons, the dynamic effect of intake air can be effectively utilized over a wide range of engine speeds.

[0024]

As explained above, according to the engine intake system according to the invention of claim 1, the independent intake passages that independently communicate with each cylinder for each cylinder row are gathered in a small gathering part, Since each of the small gathering parts is arranged on the side of one cylinder row, the overall height of the engine can be suppressed while ensuring a certain length of each of the independent intake passages. Since the collective passages are close to each other, the upstream intake passage does not become long, and the intake system passage can also be made more compact, making it possible to effectively make the engine more compact. In addition, there is a communication path that communicates the centers of the small gathering parts with each other, and the communication path is equipped with an on-off valve that opens and closes according to the engine speed, so that the dynamic effect of intake air can be controlled over a wide engine speed range. Supercharging can be performed. Furthermore, since the intake passages are of equal length and are made into small gathering parts, the distribution of the intake air to each cylinder is improved, and the dynamic effect of the intake air can be achieved without variation among the cylinders. This can further enhance the effectiveness of the project.

In particular, in the invention of claim 2, when the engine is a V-type engine mounted horizontally with respect to the vehicle body, each small aggregate from the cylinder rows of both banks is arranged on the rear bank side. At the same time, the small clusters of the cylinder rows in the rear bank are placed on the bottom and the small clusters of the cylinder rows in the front bank are on the top. Make effective use of dead space
The overall height of the engine can be suppressed along the bonnet line while ensuring a certain length for each independent intake passage. Furthermore, since the communication path that communicates the two small-sized gathering parts is formed in an L-shape, it is possible to improve the ease of assembly when connecting the communication path to both the small-sized gathering parts.

Furthermore, in the invention as claimed in claim 3, since the vicinity of the connection between the small collecting part of the cylinder row of the rear bank and the communication passage and the upstream part of the collecting passage are supported on the engine body, the cylinder row of the front bank The small gathering part of the is supported via the communication passage, and if a heavy object such as a throttle body is installed at the connecting part that gathers into one common intake passage at the upstream part of the gathering passage, its weight will be reduced. Objects can be supported without having to be supported separately, and the number of supporting parts for the entire intake system passage can be reduced.

[Brief explanation of drawings]

FIG. 1 is a side view showing the overall configuration of an engine intake device according to an embodiment of the present invention.

FIG. 2 is a plan view showing the overall configuration of an engine intake device according to an embodiment of the present invention.

FIG. 3 is a plan view of the front bank intake manifold.

FIG. 4 is a plan view of the rear bank intake manifold.

FIG. 5 is a sectional view of essential parts.

[Explanation of symbols]

1 Engine 7 Independent intake passage 8 Intake manifold 9f, 9r Collector (small gathering part) 10f, 10
r Collective passage 12 Communication passage 14 On-off valves 51 to 56 1st to 6th cylinders Bf Front bank Br Rear bank

Claims (3)

[Claims] Claim 1: It has a plurality of cylinder rows, and for each cylinder row, independent intake passages that independently communicate with each cylinder are gathered together to form a collection passage, and further, the collection passage for each cylinder row is arranged on the upstream side. In the intake system of the engine, each of the independent intake passages is set to have the same length up to the resonance tuning point of the small volume collecting part gathered in each of the collecting passages, and each of the small collecting parts has the same length. They are all arranged on the side of one cylinder row, and are equipped with a communication passage that communicates the centers of these small clusters with each other, and the communication passage is provided with an on-off valve that opens and closes depending on the engine speed. An engine intake system characterized by: Claim 2: The engine is a V-shaped engine formed in a V-shape with two banks each having a cylinder row, and is mounted horizontally with its crankshaft oriented in the vehicle width direction with respect to the vehicle body. The small clusters from the cylinder rows of both banks are arranged on the rear bank side, and the small clusters of the cylinder rows of the rear bank are arranged below, and the small clusters of the cylinder rows of the front bank are arranged on the lower side. 2. An intake system for an engine according to claim 1, wherein said portions are arranged one above the other with said small gathering portions facing upward, and said communication passage connecting said small gathering portions is formed in an L-shape. 3. The intake system for an engine according to claim 2, wherein the vicinity of the connecting portion between the small gathering portion of the cylinder row of the rear bank and the communication passage and the upstream portion of the gathering passage are supported by the engine body.