JPH0730911Y2 - Intake device for V-type internal combustion engine - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention is a V that utilizes the inertia supercharging effect and the resonance supercharging effect.
Type internal combustion engine intake device.

<Prior Art> Some internal combustion engines employ an intake air supply system that utilizes an inertial supercharging effect and a resonance supercharging effect to improve intake charging efficiency.

In inertial supercharging, in each cylinder, a negative pressure wave generated near the intake port at the start of intake propagates at the sonic velocity to the intake pipe end, and becomes a positive pressure wave, causing intake pressure oscillation that is returned toward the intake port. I'm taking advantage of that.

That is, by matching the cycle of the intake pressure oscillation and the opening / closing cycle of the intake valve so that the positive pressure wave is transmitted to the intake valve just before the intake valve is closed, the air in which the positive pressure wave is generated is generated. It is designed to be pushed into the cylinder by inertia.

Resonance supercharging is resonance when the engine speed is tuned to the resonance frequency of the entire intake system by vibrating the intake air in the two cylinder groups through the resonance pipe in two cylinder groups that do not cause intake interference with each other. It is a supercharging system that causes a phenomenon and supercharges by increasing the pressure.

As the above-mentioned intake device, for example, the one described in JP-B-60-14169 is known. This intake device is applied to an in-line 6-cylinder engine, and controls an on-off valve provided in a collecting chamber in accordance with the level of engine rotation to achieve a resonance supercharging effect in a low speed range and an inertia supercharging in a high speed range. The effect is obtained to improve the intake charging efficiency.

On the other hand, as an intake device for a V-type internal combustion engine, for example, one shown in FIG. 8 is known (Mitsubishi Heavy Industries Technical Report vol.23, No.5,
p4 to p6, especially Figures 11 and 12).

The intake system of this V-type internal combustion engine is connected to a two-story manifold 102 with a two-story structure in which two resonance pipes 101 separated from an intake port are arranged at the rear of the engine, and from there, two intake pipes of both banks are connected. It has a structure in which two cylinder groups that do not interfere with each other are connected, and a resonance supercharging effect is obtained in the entire intake system.

<Problems to be Solved by the Invention> In order to obtain the same effect by providing the V-type internal combustion engine with the opening / closing valve described in the above Japanese Patent Publication No. 60-14169, the same effect as shown in FIG. Two-story manifold with a floor structure 10
1 is provided with a passage 103 that communicates with each other, and an opening / closing valve 104 provided in the middle of the passage 103 is opened and closed. In this case, since the intake systems of both banks are asymmetric, the passages reach each cylinder. Since the length of the intake passage differs for each cylinder, the effect of inertial supercharging differs for each cylinder, resulting in an unbalanced output.

Therefore, in view of the above conventional problems, the present invention selectively obtains the resonance supercharging effect and the inertia supercharging effect based on the engine operating state in the V-type internal combustion engine to increase the engine output and improve the fuel consumption. In addition, the objective is to sufficiently secure the inertia supercharging effect for each cylinder and to make them substantially equal.

<Means for Solving the Problems> Therefore, according to the present invention, a pair of intake manifolds communicating with each cylinder are provided in the left and right banks of a V-type internal combustion engine through resonance tubes having substantially equal resonance frequencies. Are connected to a pair of air cleaners via separate upstream resonance pipes, respectively, and both intake manifolds are communicated with each other through a communication pipe, and an on-off valve driven by a drive means is interposed in the communication pipe. Based on the load detection means for detecting the load, the rotation speed detection means for detecting the engine speed, and the detection signals output from the load detection means and the rotation speed detection means, respectively, the opening / closing valve at low speed and high load And a control means for controlling the driving means so as to open the open / close valve at high speed / high load and low speed / low load.

<Operation> In such a configuration, when the intake manifolds are made not to communicate with each other by closing the opening / closing valve at the time of low speed / high load, each intake manifold functions as a resonance container. Therefore, the intake air oscillates between the intake manifolds through the intake manifolds and the upstream resonance pipe, and when the engine speed is tuned to the resonance frequency of the intake system as a whole, a resonance phenomenon occurs and a supercharging action occurs. A large resonance supercharging effect can be obtained.

As a result, volume efficiency is increased.

Further, for example, when the intake manifolds are communicated with each other by opening the opening / closing valve at high speed and high load, the intake manifolds function as a surge tank.

Therefore, intake vibration occurs between the intake manifold and each cylinder, and when the engine speed is tuned to the resonance frequency in the vibration system, an inertia supercharging effect having a large supercharging effect is produced.

Further, for example, by opening the on-off valve at low speed and low load, an inertia supercharging effect is produced as in the case of high speed and high load, but the supercharging action is small, its volume efficiency is low, and pumping loss Fuel consumption can be improved by the reduction.

When the above inertial supercharging effect is applied, the intake systems of both banks can be configured symmetrically, so that the length of the resonance pipe can be made substantially equal for each cylinder, and there is no difference in the inertial supercharging effect between cylinders. , It is possible to eliminate the imbalance of the output for each cylinder.

<Embodiment> An embodiment of the present invention will be described below with reference to the drawings.

1 and 2 show a V-type 8-cylinder diesel engine which is an embodiment of the present invention, and FIG. 3 shows a schematic configuration diagram thereof.

In these figures, the cylinder on the right side of the crankcase 1
_{R 1, R 2, R 3} , R 4 are, cylinders _{L 1, L 2, L 3} , L 4 is disposed on the left side.

The intake air in the cylinder group X including the cylinders L ₁ , L ₄ , R ₂ , and R ₃ and the intake air in the cylinder group Y including the cylinders R ₁ , R ₄ , L ₂ , and L ₃ interfere with each other. It is designed not to cause.

The ignition order of each cylinder is R ₁ → L ₁ → R _{4 as} shown in FIG.
→ L ₄ → L ₃ → R ₂ → L ₂ → R ₃

A pair of banks 2 and 3 are attached to the left and right of the crankcase 1 in a substantially V shape on the front. An intake port 4 and an exhaust port 5 are formed in the banks 2 and 3. The exhaust port 5 communicates with the exhaust manifold 6.

The intake manifolds 7, 8 are located above the pair of banks 2, 3.
And a pair of chambers 9 and 10 are formed in the intake manifolds 7 and 8.

The air cleaners 11A and 11B are provided separately for the left and right banks 2 and 3, and the intake ducts respectively led from the air cleaners 11A and 11B, that is, the upstream resonance pipes 12 and 13 are respectively provided in a pair of intake manifolds. Are connected to the rear ends of the chambers 9 and 10 via an intake heater 14, respectively. The chambers 9 and 10 are communicated with each other via a communication pipe 15, and an opening / closing valve 16 is interposed in the communication pipe 15.

The two cylinders L ₁ , L ₄ and R ₁ , R ₄ in both cylinder groups X and Y are located at the front and rear end positions of the left and right banks 2 and 3, respectively, and the other two cylinders R in both cylinder groups X and Y, respectively. ₃ , R ₂ and L ₃ , L ₂ are 2 respectively
The cylinders L ₁ , L ₄ and R ₁ , R ₄ are arranged at intermediate positions at the front and rear ends of the banks 2 and 3 opposite to the banks 2 and 3, respectively. The built-in resonance pipes 17 and 18 connected to the cylinders L ₁ and R ₁ located at the front ends of the banks 2 and 3 are located at the rear end positions in the chambers 9 and 10 and the cylinder L ₄ located at the rear end. , R ₄ are connected to the front end positions in the chambers 9 and 10, respectively. Further, the communication resonance tubes 2 connected to the cylinders L ₃ , L ₂ and R ₃ , R ₂ located in the middle of the front and rear ends of the banks 2, 3 respectively.
3, 24 and 32, 33 are communicated with chambers 10, 9 provided corresponding to banks 3, 2 on the opposite side.

The upstream resonance tubes 12 and 13 are formed to have substantially equal lengths and are set so that resonance supercharging matching the low speed range is performed.

Further, the built-in resonance tubes 17-20 and the communication resonance tubes 23, 24, 32, 33 are
Each of them is formed to have substantially the same length, and is set so that inertia supercharging matching the high speed range is performed.

Here, the built-in resonance tubes 17, 19 and 18, 20 are composed of chambers formed by partitions in the intake manifolds 7, 8. The front end opening of this chamber communicates with the inside of the chambers 9 and 10 in the intake manifolds 7 and 8, and the rear end opening thereof is the intake manifolds 7 and 8.
It is opened at the lower surface and is connected to the cylinders L ₁ , L ₄ and R ₁ , R ₄ .

The communication resonance tubes 23, 32 and 24, 33 are intake manifolds 7, 8
It consists of intake ducts 26 and 36 connected above.

One end of each of the intake ducts 26 and 36 is an intake manifold
The other end opening is communicated with the cylinder through a chamber formed in 7,8, and the other end opening is opened in the upper wall of the front and rear end intermediate portions of the intake manifolds 7,8 to communicate with the chambers 9,10. Connected to.

On the other hand, an air cylinder 27 is provided as an actuator as a drive means for driving the opening / closing valve 16, and an air supply pipe 28 of the air cylinder 27 is connected to an air tank 29. An electromagnetic three-way valve 31 that controls air to the air cylinder 27 is interposed in the air supply pipe 28. The electromagnetic three-way valve 31 is controlled by an output signal from the control unit 30. This control unit 30 receives a load sensor as an engine load detecting means, and an output signal from a rotation speed sensor as an engine speed detecting means,
The control unit 30 has a function of control means for controlling the electromagnetic three-way valve 31 according to the engine load and the rotation speed. Specifically, the open / close valve 16 is operated at low speed / high load and high speed / low load.
Closed to open / close the valve 16 at high speed / high load and low speed / low load.
Control to open.

Next, the operation of this structure will be described with reference to FIGS.

At low speed and high load in the region A shown in FIG. 5, the on-off valve 16 is closed and the chambers 9 and 10 function as a resonance container.
Therefore, the intake air oscillates between the two cylinder groups X and Y through the chambers 9 and 10 and the upstream resonance pipes 12 and 13, and the engine speed is tuned to the resonance frequency of the intake system as a whole. When the resonance phenomenon occurs, a supercharging effect of large supercharging effect is obtained. As a result, volume efficiency is increased.

At high speed and low load in the region B, the on-off valve 16 is closed and the chambers 9 and 10 in each intake manifold function as a resonance container, but the engine speed deviates from the resonance frequency of the intake system as a whole. The feeding effect is small and the volumetric efficiency is low.

Therefore, the density of the air filled in the cylinder is reduced.

At high speed and high load in the region C, the on-off valve 16 is opened, and the chambers 9 and 10 function as surge tanks. Therefore, intake vibration occurs between the chambers 9 and 10 and the cylinders L ₁ , L ₄ , R ₂ and R ₃ and the cylinders R ₁ , R ₄ , L ₂ and L _3, and the engine rotation speed is at the resonance frequency in the vibration system. When the numbers are synchronized, a large supercharging effect is produced.

As a result, volume efficiency is increased.

At low speed and low load in the region D, the on-off valve 16 is opened, and as in the case of high speed and high load, the effect of inertial supercharging occurs but the supercharging effect is small, and its volume efficiency is at low speed and high load. Is lower than.

According to the above configuration, at low speed and high load, the volumetric efficiency becomes high due to the resonance supercharging effect, so that the fuel consumption, smoke and torque can be improved.

At high speed and high load, the volumetric efficiency becomes high due to the effect of inertial supercharging, but the built-in resonance tubes 17 and 18 connected to the cylinders L ₁ and R ₁ located at the front ends of the banks 2 and 3 are installed in the chambers 9 and 10, respectively. Since the internal resonance pipes 19 and 20 connected to the cylinders L ₄ and R ₄ located at the rear ends are communicated with the front end positions inside the chambers 9 and 10, respectively, the resonance pipes 17 to The length of 20 can be made longer than before. Therefore, the inertia supercharging effect can be increased. Further, the intake manifolds 7 and 8 are connected to the pair of air cleaners 11A and 11B via separate upstream resonance pipes 12 and 13, respectively, and are located in the middle of the front and rear ends of the built-in resonance pipes 17 to 20 and the banks 2 and 3. Cylinder L
₂ , L ₃ and communicating resonance tubes 23, 24 connected to R ₂ , R _{3 respectively}
Since 32 and 33 are formed to have substantially the same length, the intake systems of the left and right banks 2 and 3 are symmetrical, and it is possible to eliminate the output imbalance between the cylinders. As a result, output improvement, fuel improvement, smoke improvement, and exhaust gas temperature reduction can be obtained.

At low speed and low load, the effect of inertial supercharging occurs as at high speed and high load, and while the dense intake air is agitated, it is sucked into the cylinder and the combustion is improved by improving the mixing of the air and the air. It is thin and reduces pumping loss to improve fuel efficiency.

Further, according to this configuration, the intake manifolds 7, 8 are provided close to the banks 2, 3 and the intake manifolds 7, 8 are provided.
The chambers 9 and 10 and the built-in resonance pipes 17 to 20 are integrally formed with each other, and the communication resonance pipes 23, 32 and 24, 33 are integrated with the intake ducts 26, 36, respectively. Can be configured.

In this embodiment, as an example of the V-type internal combustion engine, V
Although the type 8-cylinder diesel engine is cited, the invention is not limited to this, and can be applied to, for example, a 6- or 10-cylinder diesel engine or a gasoline engine.

<Effect of the Invention> As described above, according to the intake device for the V-type internal combustion engine of the present invention, for example, at the time of low speed and high load, a resonance supercharging effect having a large supercharging effect is obtained and the volumetric efficiency is improved. When the speed is high and the load is high, the inertial supercharging effect has a large supercharging effect and the output and smoke can be improved, and at the time of low speed and low load. In addition to reducing fuel consumption by reducing pumping loss, a pair of intake manifolds communicating with each cylinder are provided in the left and right banks of the V-type internal combustion engine through resonance tubes having substantially equal resonance frequencies. Since the intake manifolds are connected to the pair of air cleaners via separate upstream resonance pipes, the intake systems of the left and right banks can be configured symmetrically and the resonance pipes can be formed to have substantially the same length. Effect of effect At the same time, since the intake systems of both banks can be configured symmetrically, the length of the resonance pipe can be made approximately equal for each cylinder, the difference in inertia supercharging effect can be eliminated from cylinder to cylinder, and the output imbalance between cylinders can be eliminated. Can be eliminated.

In addition, the intake device can be made compact, which is a great practical effect.

[Brief description of drawings]

FIG. 1 is a horizontal sectional view showing an embodiment of an intake device for a V-type internal combustion engine according to the present invention, FIG. 2 is a sectional view taken along the line XX in FIG. 1, and FIG. FIG. 4 is a configuration diagram, FIG. 4 is an explanatory diagram of an ignition sequence, FIG. 5 is a map showing a relationship between an operating state and an open / close state of an opening / closing valve, FIG. 6 is a graph showing a relationship between engine speed and volume efficiency, FIG. 1 is a schematic configuration diagram of a conventional V-type internal combustion engine intake device. 2,3 ... bank, 7,8 ... intake manifold, 9,10 ... chamber, 12,13 ... upstream side resonance tube, 17,18,19,20 ... internal resonance tube,
23,24,32,33, R ₁ , R ₂ , R ₃ , R ₄ , L ₁ , L ₂ , L ₃ , L ₄ … Cylinder

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor, written by Kitamura, 1-chome, Ii-chome, Ageo-shi, Saitama, Nissan Diesel Industry Co., Ltd. (72) Keiichi Niimura, 1-chome, Io-chome, Ageo, Saitama Prefecture Incorporated (72) Inventor Shuichi Nakamura 1-chome, Ichichome, Ageo City, Saitama Prefecture Nissan Diesel Industry Co., Ltd. (56) References: 58-165219 (JP, U) 1-19832 JP , U) Actual development Sho 59-21029 (JP, U)

Claims (1)

[Scope of utility model registration request] 1. A pair of intake manifolds communicating with respective cylinders through resonance pipes having substantially equal resonance frequencies are provided in the left and right banks of a V-type internal combustion engine, and each intake manifold is provided with separate upstream resonance pipes. While being connected to a pair of air cleaners, both intake manifolds are communicated with each other via a communication pipe, and an on-off valve driven by a drive means is interposed in the communication pipe,
Based on load detection means for detecting the engine load, rotation speed detection means for detecting the engine speed, and detection signals output from the load detection means and the rotation speed detection means, respectively.
Control means for controlling the drive means so as to close the opening / closing valve at high load and high speed / low load and open the opening / closing valve at high speed / high load and low speed / low load. An intake device for a V-type internal combustion engine.