JP3403948B2 - Variable intake device for V-type multi-cylinder internal combustion engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [0001] [0001] The present invention relates to a low-pressure internal combustion engine.
Wide rotation speed range from rotation speed range to high rotation speed range
The intake characteristics so that high volume efficiency can be obtained
To a variable intake device for a V-type multi-cylinder internal combustion engine. [0002] 2. Description of the Related Art Improving fuel efficiency of an internal combustion engine for a vehicle or the like during operation.
Reduction of internal combustion engine speed is required to reduce engine vibration
However, for that purpose, it is necessary to improve the torque during low-speed rotation.
In order to improve the torque during low-speed rotation,
The volumetric efficiency of the gas must be improved. [0003] Generally, the length and volume of the intake pipe of an internal combustion engine
Is changed according to the speed of the internal combustion engine to achieve inertia supercharging
Combined use of fruit and resonance (pulsation) supercharging effects
From the low speed range to the high speed range.
Therefore, high volume efficiency is maintained. [0004] Even in a V-type multi-cylinder internal combustion engine, the rotational speed is low.
The intake manifold length of the intake manifold in the temperature range
A structure is desired. Also, generally, the intake manifold is
In the case of having a long switching structure,
In many cases, such a high speed
Structure that has little adverse effect on the inertial supercharging effect in the speed range
desired. Further, the length of the intake pipe from the intake sound source is unequal.
In order to reduce the rumbling noise caused by
It is desired that the pipe length of the intake pipe including the ditank be made equal. I
However, especially in the case of a V-type multi-cylinder internal combustion engine,
Clear between hood and hood
The structure must be able to secure a lance, and the shape of the intake pipe
There are few degrees of freedom. It is possible to satisfy the various demands as described above.
Variable intake system for V-type multi-cylinder internal combustion engine
As described in Japanese Patent Application Laid-Open No.
There is something. The one described in this publication is opposed to a V-shape.
Branch intake pipes communicating with the cylinders of the left and right banks
Cross each surge tank with a predetermined volume
Located above the pipes and connect each branch intake pipe to the surge tank.
With a J-shaped cross-section
Branch short-circuit path that short-circuits to each surge tank
And open each branch short-circuit path according to the operating conditions.
It has a branch control valve that opens and closes. In addition, each service
In the tank-to-tank communication passage that communicates the
It has a tank control valve that opens and closes according to the turning conditions. The one described in the above publication is constructed as described above.
The engine height is kept low, and each intake pipe length and
While ensuring sufficient tank capacity, the branch control valve and
And the tank control valve open and close appropriately according to the operating conditions of the engine
Controlling, supercharging effect based on inertia and resonance
A wide range from low to high engine speeds
High volume efficiency is maintained over the rotation speed range. Also, a variable for switching the intake characteristic of the intake valve.
Valve timing switching means is provided, and the intake passage is sucked.
Internal combustion engine provided with intake passage switching means capable of switching air characteristics
Seki is also disclosed in JP-A-1-262317.
As such, it has existed conventionally. [0010] The invention of the present application is based on the public
Compared with those described in the report
Cuts intake characteristics over a wide rotation speed range up to the rotation speed range.
Higher volumetric efficiency and higher output torque
Variable intake system of a V-type multi-cylinder internal combustion engine
It is an object to provide a device. [0011] Means and Effects for Solving the Problems The present invention
Is a V-type multi-cylinder internal combustion engine that has solved the above-mentioned problems.
The invention described in claim 1 relates to a variable intake device.
Is the ignition timing at which the left and right banks explode alternately and at equal intervals
And operating characteristics of the intake valves of each cylinder of the left and right banks.
Low-speed mode and high-speed mode by changing the intake characteristics
A variable valve timing switching mechanism for switching between
The intake characteristics of the intake passage are changed between low speed mode, medium speed mode and high speed mode.
And an intake passage switching mechanism that switches between
Variable valve timing switching mechanism and intake passage switching machine
The structure can be switched according to the engine speed.
In a variable intake device of a V-type multi-cylinder internal combustion engine,
Fully symmetrical intake manifolds are located between the right banks
The intake manifold is a pair of left and right throttle bodies.
A pair of left and right first chambers to which
The right pair of first chambers is connected to each cylinder of the right and left banks.
A first pair of left and right pairs directly communicating with the respective intake ports
And the left and right pair of first chambers
Left and right chambers via a pair of first communication paths
Communicators are always in communication, almost in the valley between the left and right banks
A pair of left and right second chambers located in the center,
The left and right pairs of second chambers are
1 is connected to the base end of the intake passage,
These chambers around the entire circumference of the second chamber of the pair
The winding direction formed in a spiral with the
A plurality of pairs of second intake passages;
The pair of second intake passages is a plurality of left and right pairs of first intake passages.
Upstream of the point where each is connected to the base end of the
In the left and right plural pairs of first intake passages, these first intake passages are provided.
The intake passages are respectively connected to the pair of left and right first chambers.
Communication from the low-speed mode to the medium-speed mode.
A first on-off valve for switching between the left and right modes.
In a second communication path for communicating between the pair of first communication paths,
The communication between these first communication paths is cut off, and the intake
Second, the air quality is switched from the medium speed mode to the high speed mode.
An on-off valve is provided, and suction by switching of the second on-off valve is provided.
After switching the air characteristics, the variable valve timing switching mechanism
Switch from low-speed mode to high-speed mode
V-shaped airflow characterized by being able to
1 is a variable intake device for a cylinder internal combustion engine. The invention described in claim 1 is as described above.
The left and right vans of a V-type multi-cylinder internal combustion engine
Have an ignition timing that explodes alternately and at regular intervals, and
The variable valve timing switching mechanism depends on the engine speed.
Change the operating characteristics of the intake valves for each cylinder in the left and right banks.
With this, the intake characteristics of the low-speed mode and high-speed mode
The intake passage switching mechanism changes the engine speed
Depending on the intake characteristics of the intake passage, low-speed mode and medium-speed mode
Switch between high-speed mode. [0013] The left and right banks are arranged completely symmetrically.
A pair of left and right first chambers of an intake manifold to be installed
And a pair of left and right second chambers, and a pair of left and right first chambers.
The left and right chambers are always connected via the communication passage.
Left and right pair of first chambers
Directly communicate with the intake port of each cylinder in the bank
A plurality of left and right first intake passages are provided, and a pair of left and right first intake passages are provided.
2 chambers at the base end of the first pair of left and right intake passages
And a pair of spiral right and left windings
2 intake passages cover the entire circumference of the pair of left and right second chambers.
Around these chambers and form a spiral
You. [0014] Then, a plurality of pairs of second intake passages of right and left windings are provided.
The roads are respectively connected to the base end portions of the left and right plural pairs of the first intake passages.
Left and right pairs of first intakes upstream of the point where they are connected
In the passage, a pair of left and right first intake passages is formed.
Of the air intake passage
First on-off valve for switching the valve from low-speed mode to medium-speed mode
Is disposed, and a second communication path between the pair of left and right first communication passages is provided.
The communication between the first communication paths is blocked in the two communication paths.
To change the intake characteristics of the intake passage from the medium speed mode to the high speed mode.
A second on-off valve is provided for switching to. [0015] Further, intake air by switching the second on-off valve.
After switching the characteristics, the variable valve timing switching mechanism
Switching from low-speed mode to high-speed mode with intake characteristics
It is made to do. As a result, the engine is operated at a low speed including an extremely low rotational speed.
When in the low speed mode that is the rotation speed range, the first opening and closing
The valve is closed and the left and right pair of the left and right plural pairs of the first intake passages
Direct communication with the first chamber
On the left and right sides.
, The intake passage is divided into a first intake passage and a second intake passage.
And can be made extremely long using
The road length can be made extremely long,
Second, the second on-off valve is opened, and the second communication passage is opened.
As a result, the left and right first communication passages are communicated with each other,
The first intake passage and the second intake passage are a pair of left and right.
All of the first chamber and the pair of left and right second chambers
Communication with all chambers for a single large volume inertia
A chamber can be formed. these
High inertia supercharging effect adapted to the low speed mode of the engine
And high volumetric efficiency can be obtained,
Output torque in speed mode can be improved
You. Furthermore, it is supplied to the intake port of each cylinder, respectively.
Interference of intake air can be prevented. Further, the first on-off valve increases the engine speed.
It is released when it reaches the medium speed mode where
At this time, a plurality of left and right first intake passages are
Left and right are directly connected to the left and right first chambers, respectively.
The intake passage uses a plurality of pairs of left and right first intake passages.
And the intake passage length is minimized,
High intake efficiency by suppressing the flow resistance of intake air flowing through the intake passage
To the medium speed mode of the engine.
Suitable high inertia supercharging effect and high volumetric efficiency
Obtainable. Further, the engine speed further increases and becomes higher.
When reaching the high-speed mode in the rotation speed range, the second on-off valve
Is closed, the second communication path is closed, and a pair of left and right
Left and right chambers through the first communication path
A pair of left and right first chambers that are always in communication
And the pair of left and right second chambers are completely
Independent, the intake stroke (ignition timing) does not overlap
The left and right chamber system is configured. The left and right chamber system is composed of left and right
Several pairs of first intake passages and multiple pairs of right and left-handed second pairs
Via the intake passage to the intake port of each cylinder in the right and left banks
The left chamber system is connected to the right bank
For the intake port of each cylinder,
Indicates the intake port for each cylinder in the left bank.
It functions as a resonance chamber as the atmospheric pressure equivalent part of the air passage
During the intake stroke in each of the left and right banks
Has a resonance (pulsation) effect on other cylinders,
High resonance efficiency and high volumetric efficiency
Wear. Furthermore, the engine speed continues to increase.
Variable valve timing switching mechanism
Mode to high-speed mode, so the intake valve
Improved operating characteristics and can take in a large amount of intake air
Become so. Note that the first on-off valve remains open.
And the second on-off valve is still closed,
Increased suction efficiency by suppressing the flow resistance of intake air flowing through the passage
And the intake stroke in each of the left and right banks
The resonance (pulsation) effect that propagates to other cylinders in the
As a result, high volume efficiency can be obtained. By these
Higher resonance supercharging effect and higher body
Product efficiency can be obtained. [0021] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG.
One embodiment of the invention described in claim 1 of the present application
Will be described. FIG. 1 shows a variable intake device according to the present embodiment.
Schematic plan view of a V-type multi-cylinder internal combustion engine to which the arrangement is applied, FIG.
Is a cross-sectional view taken along line II-II in FIG. 1, and FIG.
FIG. 4 is a sectional view taken along the line II-III of FIG.
FIG. 5 is a cross-sectional view taken along the line arrow, and FIG.
FIG. 6 is an exploded perspective view of the manifold, and FIG. 6 is a left view of the intake manifold.
Schematic of the connection configuration of the half chamber and intake passage
FIG. 7 is an explanatory view showing the variable state of the intake manifold.
FIG. 8 is an explanatory view showing one operation state of the intake mechanism, and FIG.
FIG. 9 is an explanatory view showing an operation state, and FIG.
FIG. 10 is a characteristic diagram of the variable intake device of FIG.
is there. FIGS. 2 and 3 show the vehicle traveling direction.
Because it is a cross-sectional view drawn from the front to the rear,
The left and right in the row direction are opposite in these figures.
To be. Therefore, for example, left and right banks 4
l and 4r are respectively shown on the right and left of the figure in these figures.
Is drawn. Hereinafter, unless otherwise specified, "Left
“Right” means left and right as viewed in the vehicle traveling direction. FIGS. 1 to 4 show the present embodiment.
V-cylinder internal combustion engine 1 to which a variable intake device is applied
Is a vertical V-type 8-cylinder internal combustion engine,
Mounted on the front part, inside the V-shaped cylinder block 5
Is a flat crank (not shown) (180-degree crank).
Rank) is accommodated, and the vehicle travels in the cylinder block 5
Left and right cylinder heads 6l, 6r,
Left and right cylinder head covers 7l, 7r
 An oil pan 8 is provided below the cylinder block 5.
The left and right banks 4l, 4r are attached together.
Main body 2 of a V-type 8-cylinder internal combustion engine
You. Left and right banks 4l, 4r explode alternately and at equal intervals
Between the two banks 4l and 4r
Is provided with the intake manifold 3 accommodated therein. The intake manifold 3 is independent on each of the left and right
Left and right intake systems 3l, 3r, as described later,
Four separate parts are assembled together and are completely symmetrical
(However, the phase is slightly shifted in the vehicle traveling direction.
You. ). The left and right intake systems 3 constituting the intake manifold 3
l and 3r are the intake ports of each cylinder of the right and left banks 4r and 4l.
To 11r and 11l (see FIG. 2; 11l is not shown).
Each supplies intake air. The intake manifold 3 will be described later
As shown in the figure, variable intake (tube length switching, resonance switching) means
ing. Although not shown, the left and right exhaust manifolds are not shown.
The field is also completely symmetrical. The left and right intake systems 3l, 3r of the intake manifold 3
And the right and left banks 4l, 4r are shown in FIGS.
Is drawn on the same side as left and right, but left and right intake systems 3l, 3
r each intake air flowing in the right and left banks 4r
 Flow into the intake ports 11r and 11l of each 4l cylinder.
Enter. The left and right intake systems 3l and 3r will be described in detail later.
However, FIGS. 6 and 7 schematically show
Have been. In FIG. 6, 3r is not shown.
No, but has the same configuration as 3l. The upstream ends of the left and right intake systems 31 and 3r are provided with surges.
Left and right chambers functioning as tanks (first chamber
-) It is 40l and 40r. 40l of the first chamber
 , 40r are each airtight with two casing blocks
Are connected to each other by bolts.
One of the casing blocks
The inner halves 41l and 41r are intake manifolds to be described later.
The door case 20 is formed integrally with the door case 20 by casting.
Outer half (throttle base) 42 l
 , 42r are slots provided at the center in the longitudinal direction.
Together with the body mounting flanges 43l and 43r
Left and right which are integrally formed to constitute the intake manifold 3
It is a pair of independent components. In addition, 10l, 10r
Is the throttle body, 13l and 13r are the throttle body 10.
l, Throttle valve installed inside 10r. First intake passage portions of left and right intake systems 31 and 3r
The four pairs of left and right branch intake pipes 21l and 21r
5, the left and right branch intake pipes as better illustrated
21l and 21r are arranged so that they alternate one by one
And the respective inner halves 41l, 41 of the second chambers 40l, 40r
r together with the intake manifold
Form the intake manifold upper 20 that forms the upper part of C3
are doing. The intake manifold upper 20 is also provided below it.
The left and right formed in the intake manifold drawer 30 described later
The pair of chambers (second chamber) 31l and 31r
They communicate with each other and surround them in a spiral shape.
Winding) Arcs that form part of the four pairs of spiral pipes 32l and 32r
32l₁, 32r₁And terminal part 32l_Three, 32r_ThreeAnd have together
(See FIG. 2. 32r, 32r₁, 32r_ThreeIs illustrated
Not. ). The left and right four pairs of spiral pipes 32l, 32r are
A second intake passage of the intake systems 3l, 3r is formed. The left and right spiral pipes 32l and 32r are the left spirals.
The winding direction of the winding pipe 32l is right-handed,
The winding direction of Ip32r is left-handed, and the winding directions are
In the opposite direction, cross each other one by one
Four pairs are formed and their ends 32l_Three, 32r_ThreeIs left
At the base end of the right four pairs of branch intake pipes 21l and 21r respectively
They are tangentially connected. Left and right spiral pipe 32l
 32l, central part 32l_Two, 32r_TwoIs a pair of left and right second
The members 31l and 31r are surrounded in a substantially U-shape.
(See FIG. 2. 32r_TwoIs not shown. ). The end portions 32l of the spiral pipes 32l, 32r_Three, 32
r_ThreeIs connected to the base end of the left and right branch intake pipes 21l and 21r.
Left and right branch intake pipes 21l, 21r on the upstream side
Inside, as shown in FIG.
1 open / close valve) 27l and 27r are provided on the left and right, respectively.
(27r not shown), the pipe length switching valves 27l, 27r
By opening and closing the first chambers 40l, 40r
The left and right branch intake pipes 21l and 21r communicate with each other and disconnect
Is done. The pipe length switching valves 27l and 27r are
Common valve shafts 44l, 44 according to operating conditions (rotational speed, vehicle speed, etc.)
r and a pair of diaphragms 28l via a link mechanism,
Opening / closing is controlled by 28r (see FIG. 1). This pair of
The ear flams 28l and 28r have one common negative pressure chamber.
One-piece diaphragm, right of the last row in the vehicle traveling direction
Attached to the center of the rear wall of the branch intake pipe 21r
I have. Four pairs of left and right branches of the intake manifold upper 20
End faces of lower opening of intake pipes 21l and 21r, spiral pipe
32l, 32r arc-shaped base end 32l₁, 32r₁And terminal part 32l_Three, 32
r_ThreeThe lower open end faces of the internal combustion engine are flush with each other.
Left and right cylinder heads 6l, 6r of body 2 and intake manifold
A mounting surface A to the hold drawer 30 is formed. But
Therefore, the intake manifold 3 can be moved to the left
It is placed and fixed on the right cylinder heads 6l and 6r,
It is disposed between the left and right banks 4l, 4r. Below the intake manifold upper 20, there is an intake
Intake manifold drawer 30 that forms the lower part of manifold 3
Are airtightly and integrally attached by bolts. Sucking
The air manifold drawer 30 is inverted as shown in FIG.
It consists of a casting block with a contour of a square shape.
In the center of the part, as shown in FIGS.
Left and right pair of chambers (second chamber) 31l, 31r
Are formed so as to communicate in the length direction (in FIG. 4,
31r is not shown). In the second chambers 31l and 31r, the ceiling
Left and right four pairs of upper openings 33l, 33r alternate in the length direction on the well surface
The upper openings 33l, 33r are formed in the second channel.
Four pairs of vortices surrounding the chambers 31l and 31r in a spiral
Arc-shaped base end 32l of wound pipe 32l, 32r₁, 32r₁Into it
Each is connected for communication. Therefore, a pair of left and right second chambers
31l, 31r are four pairs of left and right upper openings 33l, 33r and left
Four pairs of right and left pairs via the right four pairs of spiral pipes 32l and 32r
Are connected to the base ends of the intake pipes 21l and 21r, respectively.
(See arrows in FIGS. 2 and 5. In FIG. 2, 32r
 , 21r are not shown. ). A pair of left and right first chambers 40l, 40r
Are their lengths as illustrated in FIGS. 3 and 5.
The central part of the direction communicates via the communication path (second communication path) 22
Connected as possible. The communication path 22 includes a resonance switching bar.
A lube (second on-off valve) 24 is provided,
By opening and closing the valve 24, the communication path 22 is connected and disconnected.
Passed through. The communication passage 22 is provided in each of the left and right banks 4l and 4r.
It is formed so as to be located at the center in the arrangement direction of the tubes.
I have. The resonance switching valve 24 is connected to the engine operating state (rotational
Speed, vehicle speed, etc.) via the link mechanism 25.
Opening / closing is controlled by the ram 26 (see FIG. 1). This resonance cut
The exchange valve 24 is provided as shown in FIGS.
And the communication passage of the intake manifold upper 20
From the opening formed in the upper vessel wall where the 22 is formed
The valve shaft is inserted into the passage 22 and the tip of the valve shaft is connected to the intake manifold.
It is mounted on the bearing of the inner wall of the door
Have been. The diaphragm 26 includes diaphragms 28l, 28
r close to r
Diaphragms 26, 28l, 28r with intake manifold 3
They are arranged on the rear wall in both traveling directions. A pair of left and right second chambers 31l, 31r
Are located at the center in the longitudinal direction through communication passages 23l and 23r.
And the left half portion 22l of the resonance switching valve 24 of the communication passage 22
And the right half portion 22r.
Through the left half 22l and the right half 22r of passage 22
And a pair of left and right first chambers 40l and 40r, respectively.
Communication is established. Therefore, a pair of left and right second chambers
31l, 31r and a pair of left and right first chambers 40l, 40r
These communication passages (the communication passage 23l and the left half 22 of the communication passage 22)
l, left and right through the communication passage 23r and the right half 22r of the communication passage 22
Each chamber is always in communication.
The communication passages 23l and 23r are also provided for the cylinders of the left and right banks 4l and 4r.
It is formed so as to be located at the center in the arrangement direction.
The intake manifold upper 20 and the intake manifold
A. The communication passage 23l and the left half 22l of the communication passage 22 communicate with each other.
A pair of left and right combined passages of the road 23r and the right half 22r of the communication passage 22
Constitute a pair of left and right first communication paths. Second run
As described above, the communication path 22 forming the path is a pair of left and right
Connect the first chambers 40l and 40r so that they can communicate with each other.
However, at the same time, communication between the pair of left and right first communication passages is also possible.
And connect the engine to low and medium speed modes as described below.
When the resonance switching valve 24 is opened in
First chambers 40l, 40r and a pair of left and right second chambers
A total of four chambers 40l with left and right with members 31l and 31r,
Can communicate between all of 40r, 31l, 31r
You. In this manner, a total of four chambers on the left and right sides
-Communication between all 40l, 40r, 31l, 31r
Sometimes these chambers are in left and right banks 41, 4
The right and left intake systems for the intake ports 11l and 11r of each cylinder of r
3r, 3l via the first intake passage and the second intake passage
Function as a single large-volume inertial chamber
It is possible to improve the volumetric efficiency based on the sexual supercharging effect. Ma
The intake ports 11l of each cylinder of the left and right banks 4l, 4r,
Prevent interference of intake air supplied to 11r. A pair of left and right first chambers 40l,
40r and a pair of left and right second chambers 31l and 31r
As described, the left and right through the pair of left and right first communication passages
Each chamber is always in communication,
These left and right chamber comrades are described later.
In the high-speed mode of the engine, the resonance switching valve 24 is closed.
And the communication passage 22 is cut off (disconnected).
The left and right chamber systems are completely independent. This
The left and right chamber systems are right and left banks 4r, 4l cylinders
Independent intake stroke weight for each bank
Resonant supercharging effect by functioning as a resonance chamber
To improve volumetric efficiency. The left and right intake systems 3l, 3r
In the bar system, the first intake passage section (four pairs of left and right branch intake pie
21l, 21r) and the second intake passage (4 pairs of left and right spirals)
Pipes 32l, 32r) are connected and connected.
(See FIGS. 2 and 6). The V-type multi-cylinder internal combustion engine 1 in the present embodiment
Although not shown in detail in FIG.
Variable valve timing switching mechanism 12l
 , 12r (see FIG. 2). The variable valve timing mechanisms 12l, 12r
Is changed by changing the operating characteristics of the intake valve.
To low speed mode L_OAnd high-speed mode H_iCut in two steps between
(See FIG. 10), which will be described later.
As described above, the high-speed motor
Low speed mode L_OTo high-speed mode H_iCut into pieces
To increase the lift of the intake valve, and
And the valve closing time is delayed. Next, the V-type multi-cylinder internal combustion engine in this embodiment
The operation and effect of the variable intake device of the engine 1 will be described.
First, the intake manifold 3 is used for pipe length switching and resonance switching.
It has a variable intake function based on Now, the rotational speed N of the internal combustion engine 1_eIs the prescribed low
Speed N₁In low-speed mode, which is a lower low-speed range
If there is (N_e<N₁), Shown in FIGS. 7 and 10
So that the pipe length switching valves 27l and 27r are closed,
When the resonance switching valve 24 is opened, the first pair of left and right
Members 40l, 40r and four pairs of left and right branch intake pipes 21l, 21
The direct communication with r is cut off. The communication passage 22 and the left and right communication
Passages 23l, 23r, a pair of left and right second chambers 31l, 31
r, left and right (right and left winding) four pairs of spiral pipes 32l, 32r
6 (see channel B in FIG. 6 and FIG. 7).
Air cleaner, not shown, left and right throttle bodies
10l, 10r, a pair of left and right first chambers 40l,
The intake air taken into the 40r
The cylinders of the right and left banks 4r and 4l (# 1
♯8) are supplied to the intake ports 11r and 11l, respectively.
You. Therefore, in this state, the left and right
To the intake ports 11l, 11r of the cylinders 4l, 4r
The intake passage length (intake pipe length) of the right and left intake systems 3r and 3l is sufficient.
Min., Including the extremely low engine speed range
High inertia supercharging effect suitable for the low speed mode of the engine
And high volumetric efficiency can be obtained (the inertia of FIG. 10).
region). As a result, the output torque in the low speed mode of the engine
Luke can be improved. Moreover, a pair of left and right first chambers 40l
 , 40r and a pair of left and right second chambers 31l, 31r
Means that all four chambers are in communication
Since the bar capacity is secured, a standard air intake system
Or larger chamber volume than the base engine
Chamber volume, a single large volume
Function as an inertial chamber for
And further improve volumetric efficiency. Also,
Prevents reduction in volumetric efficiency in low-speed mode caused by interference
Stop. Next, the rotational speed N of the internal combustion engine_eIs medium rotation speed
When the speed reaches the medium speed mode (N₁<N_e<
N_Two), As shown in FIG. 8 and FIG.
The exchange valves 27l and 27r are opened, and a pair of left and right first chambers is opened.
Members 40l, 40r and four pairs of left and right branch intake pipes 21l, 21
r is short-circuited, and the intake passage length is minimized (see FIG. 6).
Flow path C, see FIG. 8), high suitable for the medium speed mode of the engine
Inertia supercharging effect is obtained and high volume efficiency can be obtained.
(Inertial region of FIG. 10). During this time, resonance switching
The valve 24 is kept open. The rotational speed N of the internal combustion engine_eBut higher rotation speed
When the high speed mode is reached (N _Two<N_e), Fig. 9
As shown in FIG. 10 and FIG.
And the pipe length switching valves 27l and 27r remain open.
The left and right banks 4l and 4r are completely
Will have separate right and left intake systems 3r and 3l
The intake ports 11l of each cylinder of the left and right banks 4l, 4r,
A pair of right and left first chambers 40r and 40 communicating with 11r
l and the pair of right and left second chambers 31r and 31l
Demonstrating the function of independent resonance chambers, right and left
Four pairs of branch intake pipes 21r, 21l and four pairs of right and left spirals
Left and right banks 4l, 4l through both pipes 32r, 32l
r to the other cylinders during the intake stroke in each bank
Has a resonance (pulsation) effect, and has a high overall resonance supercharging effect
Fruit and high volumetric efficiency can be obtained (Fig. 1
0 resonance region). Next, the variable valve timing mechanisms 12l, 12
r exhibits additional variable intake characteristics as follows:
You. Revolution N of internal combustion engine_eContinued to rise
High speed mode (N_Two<N_Three
<N_e) Is reached, as shown in FIG.
The switching valves 27l and 27r and the resonance switching valve 24 are in the previous state.
Is maintained, but the variable valve timing mechanisms 12l and 12r
Is low speed mode L_OTo high-speed mode H_iSwitched to
The lift of the intake valve is raised and the valve opening timing is advanced
At the same time as the exhaust valve is opened.
The overlap with the period is increased so that the intake valve
Operating characteristics are improved. As a result, the intake characteristic of the intake passage is changed to the high speed mode.
To take in more air than the air intake volume
Will be able to Moreover, the intake air flowing through the intake passage
Inhalation efficiency can be increased by suppressing flow resistance,
Other during the intake stroke in each bank 4l, 4r
High overall due to resonance (pulsation) effect that propagates to the cylinder
A good intake characteristic (volume efficiency) can be obtained. To these
Higher resonance supercharging effect, higher
Volume efficiency can be obtained (resonance region in FIG. 10). As described above, the V-shaped multiple according to the present embodiment is
The variable intake device of the cylinder internal combustion engine 1 has an intake manifold 3
Three-stage intake characteristics by pipe length switching and resonance switching
Change, and variable valve timing switching mechanism 12l,
By changing the intake characteristics in two stages by switching 12r, the intake
The inertia caused by the inertia shown by the flow of the air column in the air passage
Supercharging effect, the positive pressure generated at the intake port when the intake valve closes
A pressure wave is generated between the intake port and the side of the intake passage that corresponds to the atmospheric pressure.
Is generated by returning as a positive pressure wave after going back and forth between
The resonance (pulsation) supercharging effect and the operating characteristics of the intake valve
By properly combining and using the supercharging effects of
The engine speed range from extremely low to extremely high.
Cuts intake characteristics into four stages over a wide range of rotational speeds.
Instead, high volume efficiency and high output torque can be obtained.
it can. Further, a pair of left and right first chambers 40l,
The center of the length of 40r is communicated through the communication passage 22 and
The central part in the longitudinal direction of the pair of right second chambers 31l and 31r
Is the left half 22l of the communication passage 22 via the communication passages 23l and 23r, right
The left half 22l and the right half are connected to the half 22r.
A pair of left and right first chambers 40l, 40r via the part 22r
Each is communicated. Moreover, these communication points
Is located at the center of the left and right banks 4l and 4r in the cylinder arrangement direction.
Therefore, in the entire engine speed range,
Intake ports 11l, 11r for each cylinder of left and right banks 4l, 4r
The distribution of intake air to the
The intake passage length of the
Can be reduced. Further, the intake manifold drawer 30 is formed.
32l, the end of the spiral pipe 32l, 32r_Three, 32r_ThreeIs the intake
A branch intake pipe 21l formed in the manifold upper 20;
21r is tangentially connected to the base end of the
The pipes 21l, 21r are connected via pipe length switching valves 27l, 27r.
Since it directly faces the first chambers 40l and 40r,
Low speed mode of the intake passage, which is the low, medium, and high rotation speed range of Seki
The shape of the intake passage in each operating state of the high-speed mode from
The shape can be made smooth and reasonable, and the intake passage
The drag is reduced, and the engine output can be improved. Further, the pipe length switching valves 27l, 27r,
The resonance switching valves 24 and their operating mechanisms are connected to the intake manifold.
Since it can be assembled and assembled on the rudder upper 20,
The intake manifold 3 can be made compact,
The amount of overhang of the internal combustion engine body 2 in the upward direction is small.
Can be suppressed. With this, the left and right banks 4l,
Efficient use of the space between 4r and variable intake function
Intake manifold 3 to the V-type multi-cylinder internal combustion engine 1
Can be mounted while holding down. In this embodiment, a V-type multi-cylinder internal combustion engine
1 is a V-type 8-cylinder internal combustion engine, but is not limited to this.
However, it is not applicable to other V-type multi-cylinder internal combustion engines such as V-type six cylinders.
Can be.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic plan view of a V-type multi-cylinder internal combustion engine to which a variable intake device according to an embodiment of the invention described in claim 1 of the present application is applied. 2 is a sectional view taken along the line II-II of FIG. 1; FIG. 3 is a sectional view taken along the line III-III of FIG. 1; FIG. 4 is a sectional view taken along line IV-IV of FIG. 1; 5 is an exploded perspective view of the intake manifold in the embodiment of FIG. FIG. 6 is an explanatory diagram schematically showing a connection configuration between an intake chamber and an intake passage on a left half side of the intake manifold. FIG. 7 is a schematic diagram showing one operation state of a variable intake device provided in the intake manifold. FIG. 8 is a schematic view showing another operation state. FIG. 9 is a schematic view showing still another operation state. FIG. 10 is a characteristic diagram of the variable intake device of FIG. 1; [Description of Signs] 1. Vertical V-type 8-cylinder internal combustion engine, 2. Internal combustion engine main body,
3 ... intake manifold, 3l, 3r ... left and right intake system, 4l,
4r: Left and right banks, 5: Cylinder block, 6l, 6r
... left and right cylinder heads, 7l, 7r ... left and right cylinder head covers, 8 ... oil pans, 10l, 10r ... left and right throttle bodies, 11l, 11r ... left and right intake ports, 12l, 12r ...
Left and right variable valve timing mechanism, 13l, 13r ... throttle valve, 14l, 14r ... left and right injector, 15l, 15r
... left and right blow-by gas passages, 20 ... intake manifold uppers, 21l, 21r ... left and right branch intake pipes (first intake passage), 22 ... communication passages (second communication passages), 22l, 22r ... left and right communication passages , 23l, 23r ... left and right communication passage (first communication passage portion), 24 ... resonance switching valve (second on-off valve), 25 ... link mechanism, 26 ... diaphragm, 27l, 27r ... left and right pipe length switching valve (first 28l, 28r: left and right diaphragms, 29l, 29r: left and right injector housing cylinders, 30: intake manifold drawers, 31l, 31r: left and right chambers (second chambers), 32l, 32r: spiral pipes (second pipes) 32l ₁ , 32r ₁ ... left and right circular base end, 32l ₂ , 32r ₂ ...
Left and right central part, 32l ₃ , 32r ₃ ... right and left end part, 33l, 33r ... left and right upper opening, 40l, 40r ... left and right chamber (first chamber), 41l, 41r ... left and right inner half, 42l, 42r ... left and right Outer half body (throttle base), 43l, 43r ... Left and right throttle body mounting flanges, 44l, 44r ..., A ... Mounting surface, B ..., C ... intake passage.

──────────────────────────────────────────────────続 き Continuation of front page (51) Int.Cl. ⁷ identification code FI F02M 35/104 F02M 35/10 102Y (58) Investigated field (Int.Cl. ⁷ , DB name) F02B 27/02 F01L 13 / 00 301 F02D 13/02 F02D 41/04 320 F02D 43/00 301 F02M 35/104

Claims (1)

(57) [Claim 1] Left and right banks have ignition timings that explode alternately and at equal intervals, and intake characteristics are changed by changing operation characteristics of intake valves of respective cylinders of the left and right banks. A variable valve timing switching mechanism for switching between a low speed mode and a high speed mode, and an intake passage switching mechanism for switching an intake characteristic of an intake passage between a low speed mode, a medium speed mode, and a high speed mode. In a variable intake device for a V-type multi-cylinder internal combustion engine in which a switching mechanism and the intake passage switching mechanism can be switched according to an engine speed, an intake manifold that is completely symmetrical between the left and right banks is disposed between the left and right banks. A pair of left and right first chambers to which a pair of left and right throttle bodies are connected; and a pair of right and left first chambers. A plurality of left and right pairs of first intake passages directly communicating with the intake ports of the respective cylinders of the ink tank; and the left and right chambers are always connected to the left and right pair of first chambers via the left and right pair of first communication passages. A pair of left and right second chambers which are communicated with each other and are located at a substantially central portion between valleys of the left and right banks; and a base end of the left and right plural pairs of the first intake passages. And a plurality of pairs of second intake passages formed in a spiral shape integrally with these chambers around the entire periphery of the pair of left and right second chambers, the winding directions being right and left winding. A plurality of pairs of left and right-handed second intake passages are respectively connected to the base ends of the first pair of left and right intake passages. , These first A first opening / closing valve is provided for communicating an intake passage with the pair of left and right first chambers and switching an intake characteristic of the intake passage from a low speed mode to a medium speed mode. A second opening / closing valve is disposed in the second communication passage for communicating between the first communication passage and the second opening / closing valve for shutting off communication between the first communication passages and switching the intake characteristic of the intake passage from the medium speed mode to the high speed mode; After switching the intake characteristic by switching the second on-off valve,
A variable intake device for a V-type multi-cylinder internal combustion engine, characterized in that the intake characteristic can be switched from a low speed mode to a high speed mode by the variable valve timing switching mechanism.