JPH041298Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) This invention relates to the intake pipe structure of a V-type engine, and in particular the connection of independent intake passages that connect the surge tank and intake port provided above between the left and right banks. Concerning improved structure.

(Prior art) In V-type engines, in order to downsize the engine and ensure the length of the intake pipe, the intake ports of each bank are opened on the opposing inner surfaces of both the left and right banks, and the intake ports are opened above between the two banks. A surge tank is provided with a plurality of intake passages extending from a side of the surge tank and extending from the opposite side of the surge tank below the surge tank and intersecting with each other and connected to each intake port of the opposite bank. It is common to provide an independent intake passage.

By the way, since each independent intake passage has a complicated curved shape, it is difficult to cast it as an integral part.
an independent intake pipe that is split and connected to the intake port;
In many cases, a structure is adopted in which this independent intake pipe is connected to a curved connecting pipe that connects the surge tank.

In order to shorten the process cycle when assembling the engine, the multiple independent intake pipes of each bank are integrated into the intake pipe block by welding or integral casting, and when assembling the engine, both banks are equipped with intake pipe blocks and surge tanks. are assembled one after another, and the connecting pipe is assembled last.

Conventionally, a flange connection structure has generally been adopted for the connection part structure of the intake pipe of a cast product, such as the connection part between the independent intake pipe and the connection pipe described above (for example, Japanese Patent Application Laid-Open No. 60-209623 reference).

On the other hand, the applicant filed the earlier application
No. 59829) proposed a connection structure in which a fitting flange is formed at the upper end of the independent intake pipe, and the lower end of the connecting pipe is internally connected to the fitting flange via a sealing material. .

(Problems to be solved by the invention) FIG. 2 shows the above-mentioned intake pipe blocks 100a, 10.
0b is assembled to the cylinder heads of the left and right banks 101a and 101b, and the upper end of each independent intake pipe 102 has a connecting flange 1.
03, and the three independent intake pipes 102 attached to each bank are integrally formed through the mounting flanges at their lower ends, and when assembled as shown in the figure, the left and right banks 101a, 101b
The independent intake pipes 102 of the vehicle are arranged in such a manner that they alternately approach each other and intersect with each other at their upper portions, and the independent intake pipes 102 are formed into a three-dimensionally curved shape. Therefore, the left and right banks 101a, 101
When assembling the intake pipe blocks 100a, 100b, one of the intake pipe blocks 100a, while adjusting the position and posture of both intake pipe blocks 100a, 100b outside the engine body,
The three independent intake pipes 102 of the other intake pipe block 100b are simultaneously and alternately inserted between the three independent intake pipes 102 at a position below the flange 103 of the three independent intake pipes 102 of the two intake pipes. Independent intake pipes 102 of blocks 100a and 100b
The intake pipe blocks 100a and 100b are then positioned and assembled in the corresponding banks 101a and 101b of the engine.

During the above assembly, the other intake pipe block 100
There is a problem in that the flange 103 of the independent intake pipe 102 shown in FIG.

The intake pipe connection structure proposed in the above-mentioned earlier application also has the same drawback in terms of assemblability because a fitting flange is formed at the upper end of the independent intake pipe.

In addition, in a structure in which an independent intake pipe and a connecting pipe are connected by a flange, there is a gap between the bolt hole of the flange and the bolt.
In many cases, the independent intake pipe and the connecting pipe are connected to each other in an eccentric manner, and in this case, the cross-sectional area of the intake passage decreases, resulting in a reduction in intake performance.

(Means for solving the problem) The intake pipe structure of the V-type engine according to the present invention is as follows:
An intake port of each cylinder of each bank is opened on the opposing inner surfaces of a pair of banks each having a plurality of cylinders, a surge tank is disposed above between the two banks, and a surge tank is disposed on the side of the surge tank. A plurality of independent intake passages connected at their upper ends and extending below the surge tank from the opposite side of the surge tank, intersecting in close proximity to each other and connected at their lower ends to each intake port of the opposite bank. In the intake pipe structure of a V-type engine equipped with an intake passage, each of the independent intake passages has an upper end connected to a surge tank and a connecting pipe curved downward of the surge tank, and an upper end connected to a lower end of the connecting pipe. and an independent intake pipe whose lower end is connected to an intake port, and the independent intake pipes connected to each intake port of opposite banks are arranged to intersect with each other below the surge tank. A plurality of independent intake pipes attached to the bank are integrally formed through mounting flanges at their lower ends, and the upper end of the independent intake pipe is fitted and connected to the lower end of the connecting pipe via a sealing material. It is something.

(Function) In the intake pipe structure of the V-type engine according to the present invention, intake air is supplied from the surge tank to each intake port of each bank via each independent intake passage, and each independent intake pipe is connected to the surge tank. It extends from the side of the surge tank, passes below the surge tank, and connects to the intake port of the opposite bank, resulting in an independent intake pipe passage with sufficient intake pipe length.

When assembling a plurality of independent intake pipes that are integrated into the left and right banks into a block shape via mounting flanges, the multiple independent intake pipes of one block shape must be fixed in advance outside the engine body. Then, the multiple independent intake pipes installed in the other bank are inserted into these multiple independent intake pipes so as to intersect with each other, and both are combined.Then, both are assembled into the left and right banks of the engine body, respectively. It turns out.

Here, since the upper end of the independent intake pipe is connected to the lower end of the connecting pipe through a sealing material, the diameter of the upper end of the independent intake pipe is not increased. When the plurality of block-shaped independent intake pipes of one block and the plurality of block-shaped independent intake pipes of the other block are combined in a crosswise manner, they can be smoothly combined. However, depending on the structure of the independent intake pipes and mounting flanges, it is possible to assemble one block-shaped plurality of independent intake pipes to one bank, and then attach the other block-shaped plurality of independent intake pipes to the other bank. It is not impossible to assemble it into

After assembling a plurality of block-shaped independent intake pipes to the left and right banks, a connecting pipe is connected to the upper end of each independent intake pipe. Since the independent intake pipe and the connecting pipe can be connected to each other concentrically and accurately, the independent intake pipe and the connecting pipe can be connected to each other in a concentric manner.

(Effect of the invention) According to the intake pipe structure of the V-type engine according to the invention, as explained above, the diameter of the upper end of the independent intake pipe does not increase, so the independent intake pipe can be assembled to the cylinder head of the left and right banks. Effects such as significantly improved assembling performance and the ability to connect the independent intake pipe and the connecting pipe without misalignment can be obtained.

(Example) Embodiments of the present invention will be described based on the drawings.

This embodiment is an example in which the V-type engine intake pipe structure according to the present invention is applied to a 6-cylinder V-type engine.

As shown in Figure 1, the V-type engine E has one left and one right
The pair of banks 1a and 1b form an opening angle of approximately 60° and
The cylinder blocks 2a, 2b of the left and right banks 1a, 1b are integrally arranged, and cylinder heads 3a, 3b are fixed to the upper ends of the left and right cylinder blocks 2a, 2b, respectively. 2b has three cylinder bores 4 each.
are formed, and the cylinder bores 4 of the left and right banks 1a, 1b are arranged alternately in the front-rear direction.

For each left and right bank 1a, 1b, a combustion chamber 6 is formed by the cylinder bore 4, the lower surface of the cylinder head 3a, 3b, and the upper surface of the piston 5.
An intake valve 8 is provided to open and close the downstream end of the intake port 7 connected to the intake port 7, and the intake valve 8 is driven to open and close by a valve mechanism. The intake port 7 opens on the inner side of the cylinder heads 3a, 3b.

The intake passages of the V-type engine E include a common intake passage extending from the air cleaner to the surge tank 9, the surge tank 9, and six independent intake passages 10a and 10b that independently connect the surge tank 9 and each intake port 7. An air flow meter, a supercharger, a throttle valve, etc. are installed in the common intake passage.

The surge tank 9 has left and right banks 1a and 1b.
Three independent intake passages 10a, which are arranged above the surge tank 9 and connected to the left side of the surge tank 9 at predetermined intervals in the front-rear direction, respectively curve downward from the left side and pass below the surge tank 9. Right bank 1
The surge tank 9 is connected to each intake port 7 of b.
3 connected at predetermined intervals in the front and back direction on the right side of the
Each of the independent intake passages 10b is curved downward from the right side, passes under the surge tank 9 in a crosswise manner close to the independent intake passage 10a, and is connected to each intake port 7 of the left bank 1a. .

The independent intake passages 10a and the independent intake passages 10b are arranged alternately in the front-rear direction.

Each of the independent intake passages 10a, 10b is composed of a connecting pipe 11 forming an upper half thereof, and an independent intake pipe 12 forming a lower half thereof.

The connecting pipe 11 has a curved shape with a large curvature.
The flange portion 11a at the upper end of the surge tank 9
A fitting flange portion 11b having a slightly larger diameter is formed at the lower end of the connecting pipe 11, and an independent intake pipe 12 is fastened to the peripheral portion of the side opening of the The upper end portions of the two are concentrically fitted and connected via a sealing material 14 such as an O-ring.

The upper end portion of the independent intake pipe 12 is formed to have approximately the same outer diameter as the other portions, and the sealing material 14 ensures airtightness of the fitting portion.

The independent intake pipe 12 is formed into a curved shape that gently curves toward the opposite side from the connecting pipe 11, and each bank 1
A common mounting flange 15 is integrated at the lower ends of the three independent intake pipes 12 connected to the cylinder heads 3a and 3b of cylinder heads 3a and 1b by welding or integral casting. Mounting flange part 1 on the inside of 3a and 3b
Cylinder head 3 to which three independent intake pipes 12 correspond by fastening to cylinder head 6 with four bolts 17
a, 3b, each independent intake passage 10a, 1
0b is communicatively connected to each intake port 7.

In addition, a surge tank 9 is installed in the six independent intake pipes 12.
In order to install the independent intake pipes 12 at the position corresponding to the center of the surge tank 9 in the width direction,
A boss-shaped mounting portion 18 is protruded from the upper side, and a fixing bolt 19 is inserted through the wall of the surge tank 9.
The surge tank 9 is fixed to the independent intake pipe 12 with six fixing bolts 19 by fastening them to each mounting portion 18.

Incidentally, an injector 20 for injecting fuel into each intake port 7 is attached to an upper portion near the lower end of each independent intake pipe 12, and pressurized fuel is supplied to these injectors 20 from a fuel supply pipe 21.

When assembling the six independent intake passages 10a, 10b and the surge tank 9, first the three independent intake pipes 12 on each side are assembled to the corresponding cylinder heads 3a, 3b, and then the surge tank 9 are assembled to six independent intake pipes 12, and finally six connecting pipes 11 are assembled.

Three independent intake pipes 1 for the above left bank 1a
2 and three independent intake pipes 12 for the right bank 1b
Since the diameter of the upper end of each independent intake pipe 12 is not increased when assembling the intake pipes in an alternating manner, the efficiency of assembly is greatly improved.

Since the upper end of each independent intake pipe 12 is internally connected to the fitting flange part 11b of each corresponding connecting pipe 11, the two can be connected concentrically without any displacement, so the independent intake passages 10a, 10b Not only does the cross-sectional area of the passageway not decrease, but also the connecting pipe 11 can be easily assembled.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of a main part of a V-type engine according to an embodiment of the present invention, and FIG. 2 is a plan view showing a conventional V-type engine with independent intake pipes installed in both banks. . 1a, 1b... Bank, 4... Cylinder bore,
7...Intake port, 9...Surge tank, 10
a, 10b...Independent intake passage, 11...Connecting pipe,
11b...Mating flange portion, 12...Independent intake pipe, 14...Sealing material, 15...Mounting flange.

Claims (1)

[Scope of Claim for Utility Model Registration] A pair of banks each having a plurality of cylinders has an intake port for each cylinder in each bank opened on the opposing inner surfaces thereof, and a surge tank is disposed above between the two banks. , whose upper end is connected to the side of the surge tank, intersects in close proximity with the intake passage extending from the opposite side of the surge tank below the surge tank, and whose lower end is connected to each intake passage of the opposite bank. V with multiple independent intake passages connected to ports
In the intake pipe structure of the type engine, each of the independent intake passages has an upper end connected to the surge tank and a connecting pipe curved downward from the surge tank, and an upper end connected to the lower end of the connecting pipe and a lower end connected to the intake pipe. The independent intake pipes connected to each intake port of opposite banks are arranged to intersect with each other below the surge tank, and the plurality of independent intake pipes connected to each bank are The independent intake pipes are integrally formed via mounting flanges at their lower ends, and the upper end of the independent intake pipe is internally connected to the lower end of the connecting pipe via a sealing material. V-type engine intake pipe structure.