JPH0129986B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an intake system for a V-type engine.

(Prior art) V in which one cylinder group and another cylinder group are arranged in a V shape.
In the type engine, a surge tank defining an intake expansion chamber is provided in the space formed between the two cylinder groups, that is, the central space of the V bank, and an independent intake pipe is connected between the surge tank and each cylinder. There is a type in which each air intake passage is connected independently using independent intake passages (see Japanese Patent Application Laid-open No. 101055/1983). Since the independent intake pipe is generally located below the surge tank, the surge tank is often placed on and fixed to the independent intake pipe. Conventionally, the surge tank was placed on a connecting flange formed at the upper open end of the independent intake pipe, and a mounting bolt passing through this connecting flange was screwed into the bottom wall of the surge tank from below. Therefore, this surge tank was fixed to an independent intake pipe.

However, in the conventional surge tank installation method described above, the installation work using the mounting bolts must be done from below the surge tank within a relatively narrow V bank while avoiding the independent intake pipe, which is extremely inefficient. It had become a thing.

Incidentally, in recent years, in order to improve charging efficiency through inertial supercharging, the length of the independent intake pipe has been increased as much as possible. Therefore, it is desired that each cylinder group is divided into two chambers so that resonant supercharging can also be obtained (generally, the cylinders in each cylinder group are not lit in the same order). ). In order to increase the length of the independent intake pipe in order to obtain the above-mentioned inertial supercharging, it is not possible to extend the independent intake pipe vertically to the position of the surge tank. It is desirable to have an appearance that almost traverses the groups. However, in this case,
Since it is impossible to position the connecting flange of the independent intake pipe below the surge tank, some kind of measure is required to secure the surge tank.

(Objective of the Invention) The present invention was made in consideration of the above-mentioned circumstances. When the length of the independent intake pipe is increased to obtain inertial supercharging, that is, when the independent intake pipe passes under the surge tank, In such cases, an intake system for a V-type engine in which a surge tank with two intake expansion chambers for each cylinder group defined by a partition wall can be easily fixed to an independent intake pipe is provided. The purpose is to provide.

(Structure of the Invention) In order to achieve the above-mentioned object, the present invention basically includes a surge tank placed on the side wall (pipe wall) of the independent intake pipe, and The surge tank is fixed.

Specifically, the partition wall that divides the intake expansion chamber into two chambers is extended in the vertical direction, and a boss part that extends in the vertical direction is formed on this partition wall, and a mounting bolt is inserted through the boss part. , the surge tank is fixed to the side wall.

With this configuration, the surge tank can be installed from above the surge tank, which has a wide working space, without being obstructed by the independent intake pipe, using the mounting bolts, making the work easier. The quality will be extremely good.

(Example) Examples of the present invention will be described below based on the attached drawings.

In FIG. 1, 1 is one cylinder group, 2 is another cylinder group, and both cylinder groups 1 and 2 form a V-shape with each other, and each has three cylinders arranged in series in a direction perpendicular to the plane of the paper. It is a component of a V-type 6-cylinder engine. The firing orders of the cylinders in one cylinder group 1 are not adjacent to each other, and accordingly, the firing orders of the cylinders in the other cylinder group 2 are also non-adjacent. In other words, the ignition order is one cylinder in cylinder group 1, one cylinder in cylinder group 2, one cylinder in cylinder group 1, etc.
It is set like this.

The space A, that is, V between these two cylinder groups 1 and 2
A surge tank 3 is disposed in the central bank space and extends in the cylinder arrangement direction of the cylinder groups 1 and 2 (direction perpendicular to the plane of the paper in FIG. 1). The interior of the surge tank 3 is an intake expansion chamber B, and three connection ports 4 and 5 are opened in series in the direction perpendicular to the plane of the paper on the left and right sides of the surge tank 3, respectively, as shown in FIG. ing. As shown in FIGS. 2 and 3, the intake expansion chamber B is divided between the right ventricle _B1 and the left ventricle _B2 by a partition wall 3a extending vertically within the surge tank 3. A connection port 4 defined in the chamber and opened to this right chamber _B1 is for one cylinder group 1,
Each of the cylinders of this one cylinder group 1 is connected to an intake port 6 provided individually through a branch pipe 7 as an independent intake pipe. In addition, the connection port 5 opened to the left chamber B ₂ is for the other cylinder group 2, and the intake port 8 provided individually for each cylinder of the other cylinder group 2 is
They are connected via branch pipes 9, each serving as an independent intake pipe. Of course, the closed circuit from the connection ports 4 and 5 to the intake ports 6 and 8 via the branch pipes 7 and 9 is
This constitutes an independent intake passage.

The intake ports 6 and 8 in both cylinder groups 1 and 2 are
Each of the branch pipes 7 and 9 is opened toward the other cylinder group, that is, toward the V-bank central space A, while the branch pipes 7 and 9 are once extended away from the side of the surge tank 3 and then bent back approximately 180 degrees. , after that passing below the surge tank 3, that is, V
It is inclined so as to cross the bank central space A from side to side, and is connected to the intake port 6 or 8. By doing so, the length of the branch pipes 7 and 9 can be made sufficiently long. This provides an inertial supercharging effect.

Further, in the embodiment, the branch pipe 7 includes a first branch pipe 7a having a substantially U-shape that connects to the connection port 4 of the surge tank 3, and a gently curved first branch pipe 7a that connects the first branch pipe 7a and the intake port 6. a second branch pipe 7b;
This second branch pipe 7b is located below the surge tank 3. In addition, branch pipe 9
Similarly to the branch pipe 7, the first branch pipe 9 is approximately U-shaped.
a, and a gently curved second branch pipe 9b that connects the first branch pipe 9a and the intake port 8, and the second branch pipe 9b is located below the surge tank 3. . That is, the two second branch pipes 7b and 9b are crossed with each other below the surge tank 3, and the two second branch pipes 7b and 9b, which are crossed in this way, are integrally molded by casting or the like. It is said to be X. That is,
Three second branch pipes 7b and three second branch pipes 9b
and are integrally molded. Also, 3
The first branch pipes 7a and the three first branch pipes 9a are also integrally molded, as shown in FIG. 2.

The upper surface of the integrally molded product X, that is, the branch pipe 7b
Alternatively, in the portion corresponding to the side wall portion of 9b, a third
As shown in the figure, two pedestal parts are spaced apart in the cylinder arrangement direction of one cylinder group 1 (other cylinder group 2).
It is assumed that X ₁ and X ₂ are integrated. Both of the pedestals X ₁ and X ₂ have flat upper surfaces,
The left and right center portions of the bottom wall of the surge tank 3 are placed on top of this. In the embodiment, one pedestal X ₁ is longer than the other pedestal X ₂ (see FIG. 3), and is placed near the intake pipe 10 (described later) disposed upstream of the surge tank 3. It is located.

On the other hand, a pedestal is provided on the bulkhead 3a of the surge tank 3.
By making the diameter slightly larger corresponding to the position _of It is formed. This bolt insertion hole 11 has a large diameter portion 11a at its upper end and is opened on the top surface of the surge tank 3, while its lower end is opened at the bottom surface of the surge tank and is inserted into this bolt insertion hole 11 for installation. The bolt 12 is inserted into the screw hole 1 formed in the pedestal X ₁ and X ₂ .
3, the surge tank 3 is fixed to the integrally molded product X. In this fixed state, the neck portion 12a of the mounting bolt 12 is located within the large diameter portion 11a of the bolt insertion hole 11, and the neck portion 12a connects the surge tank 13 to the pedestal X ₁ ,
It is pushing towards X ₂ . In addition, the surge tank 3 is not only placed and fixed on the pedestals X ₁ and X ₂ but also connected to the first branch pipes 7a and 9a with their left and right sides sandwiched between them. In the end, the surge tank 3 is supported from three directions: left, right, and below.
Sufficient mounting strength is ensured.

The surge tank 3 has an intake inlet 14 that opens into the right ventricle _B1 on the right end surface in FIG.
The intake inlet port 15 that opens into the left ventricle _B2 is opened,
The intake pipe 10 connected to an air cleaner (not shown) is connected to this right end surface. This intake pipe 10 is defined by a partition wall 10a into intake passages 10b and 10c, which are independent from each other.In this way, the left ventricle _B1 and the right ventricle _B2 of the intake expansion chamber B are separated from each other. By introducing intake air from the intake passages 10b and 10c, so-called resonance supercharging can also be obtained.

Intake ports 6 and 8 are provided near the connection portions of the second branch pipes 7b and 9b to the cylinder groups 1 and 2, respectively.
A fuel injection port 1 that extends almost vertically and opens at
6, 17 are formed, and these fuel injection ports 16, 17
The lower end portions of the fuel injection valves 18 and 19, that is, the fuel injection nozzle portions are fitted and connected to the respective fuel injection valves 18 and 19, respectively. In this way, the three fuel injection valves 18 for one cylinder group 1 and the three fuel injection valves 19 for the other cylinder group 2 are located at positions widely separated laterally within the V-bank central space A. A fuel destroyer 20 is provided for the three fuel injection valves 18, and a fuel destroyer 20 is provided for the three fuel injection valves 19.
1 is connected. Thereby, fuel is distributed and supplied from the fuel distributors 20 and 21 to the fuel injection valves 18 and 19.

In the above embodiment, the mounting bolt 12 is inserted from above the surge tank, but the mounting bolt 12 having a threaded portion at the upper end is attached to the pedestal portions X ₁ and X _{2 .}
The surge tank 3 may be fixed by protruding upwardly and screwing a nut into the threaded portion of the mounting bolt at the large diameter portion 11a of the bolt insertion hole 11.

(Effects of the Invention) As is clear from the above, the present invention has the following advantages:
Even if the independent intake pipe passes below the surge tank, the surge tank can be easily attached to the independent intake pipe.

Of course, since the boss portion through which the mounting bolt is inserted is integrally formed with the bulkhead of the surge tank, sufficient rigidity, especially the rigidity of the bottom surface of the mounting bolt, can be ensured without interfering with the flow of intake air. Installation reliability can be ensured. Furthermore, since the boss portion is located at the center of the left and right sides of the surge tank, there is good balance when tightening the mounting bolts, and together with the above, the mounting reliability can be further improved.

[Brief explanation of drawings]

FIG. 1 is a partially sectional front view showing an embodiment of the present invention. FIG. 2 is a plan view of the surge tank portion of FIG. 1. Figure 3 is a sectional view taken along the line shown in Figure 2. A: V bank central space, B: intake expansion chamber,
B ₁ : Right ventricle, B ₂ : Left ventricle, X ₁ , X ₂ : Pedestal, 1: One cylinder group, 2: Other cylinder group, 3: Surge tank,
3a: partition, 3b: boss, 7: branch pipe (independent intake pipe), 9: branch pipe (independent intake pipe), 11: bolt insertion hole, 13: screw hole, 12: mounting bolt.

Claims (1)

[Scope of Claims] 1. A surge tank disposed in a central space of a V bank between one cylinder group and another cylinder group forming a V shape and defining an intake expansion chamber; an independent intake pipe that is connected to the surge tank individually and passes below the surge tank; Each group is defined into two chambers, and a boss portion extending in the vertical direction is formed on the partition wall, and the surge tank is placed on a side wall portion of the independent intake pipe and is inserted through the boss portion. An intake system for a V-type engine, characterized in that the intake system is fixed to a side wall of the independent intake pipe with a mounting bolt.