JPH057491Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field This invention relates to an intake manifold used in, for example, an automobile engine.

In this specification, the term "aluminum" includes not only pure aluminum but also aluminum alloys. Furthermore, the term "stretched material" refers to material formed by plastic working such as extrusion, impact extrusion, and forging.

BACKGROUND OF THE INVENTION For example, conventional intake manifolds used in automobile gasoline engines equipped with electronically controlled fuel injection systems have been manufactured entirely by casting.

Problems that the invention aims to solve However, since the surface of the cast product is rough, it is necessary to finish at least the inner surface to make it smooth in order to reduce air resistance in order to improve intake efficiency, which is a tedious task. There was a problem that. Moreover, it is impossible to finish the entire inner surface of the intake manifold due to its shape, and it has not been possible to sufficiently reduce air resistance to improve intake efficiency. Further, in the case of an intake manifold made of a cast product, there is a problem in that the thickness of the peripheral wall cannot be reduced beyond a certain limit due to the flowability of the metal during casting, resulting in an increase in weight. In addition, with conventional intake manifolds, when the engine starts, the temperature inside the air passages of the intake manifold drops, so the fuel is not vaporized or atomized uniformly, causing the problem that it does not burn properly in the cylinders. It was hot. Furthermore, even while the vehicle is driving, the vehicle may be cooled by air blown by a fan or the like, causing the same problem as described above. Furthermore, due to the above reasons, the temperature inside the air passage of the intake manifold may fall below the specified temperature, or the temperature inside the intake manifold may rise above the specified temperature due to abnormally high external temperatures, etc. As a result, the amount of air sent into the cylinders of the engine may become larger or smaller than a predetermined amount, and there is a risk that normal combustion may not occur.

The purpose of this invention is to provide an intake manifold that solves the above problems.

Means for Solving the Problems In order to achieve the above object, the intake manifold according to this invention has a main pipe made of a wrought aluminum material with one end open and the other end closed, and each end connected to the main pipe. The branch pipe consists of an inner wall, an outer wall, and a radial connecting wall connecting both walls, and a plurality of hollow parts are formed between the two walls, and the inner wall The inside is an air passage, and the hollow part is filled with heat-retaining insulation material.

The above-mentioned intake manifold is applied to an internal combustion engine such as an automobile engine equipped with a carburetor or an automobile engine equipped with an electronically controlled fuel injection device.

Function The intake manifold according to this invention consists of a main pipe made of wrought aluminum material with one end open and the other end closed, and a plurality of branch pipes made of wrought aluminum material each having one end connected to the main pipe. Therefore, its inner surface is smoother than the conventional intake manifold, which is entirely made of a cast product.

In addition, the branch pipe consists of an inner wall, an outer wall, and a radial connecting wall that connects both walls, and a plurality of hollow parts are formed between the two walls, and the inside of the inner wall is used as an air passage, and the inside of the hollow part is used for heat retention. Filled with insulation material, the temperature inside the intake manifold branch pipe can be maintained at an appropriate temperature.

Embodiments Hereinafter, embodiments of this invention will be described with reference to the drawings. The same parts and parts are denoted by the same reference numerals throughout the drawings.

1 to 3, the intake manifold includes a main pipe 10 made of a wrought aluminum material with one end open and the other end closed, and a plurality of extruded aluminum pipes each having one end connected to the main pipe 10. A branch pipe 30 is provided.

The main pipe 10 consists of an extruded aluminum pipe 11 and a lid 12 made of wrought aluminum material which is brazed to one end of the extruded pipe 11 to close the opening of the pipe 11. The extruded pipe 11 has a substantially U-shaped cross section 11a.
and a flat portion 11b that closes the opening of the U-shaped portion 11a. The U-shaped portion 11a has an inner and outer double structure, and integrally connects an inner wall 15, an outer wall 16, and both walls 15, 16 over the entire length, and divides the space between the two walls 15, 16 into four hollow portions 18. It consists of two connecting walls 17. A portion surrounded by the inner wall 15 and the flat portion 11b serves as an air passage 19, and the inner wall 15 serves as a partition wall separating the air passage 19 and the hollow portion 18. The hollow portion 18 is filled with a heat insulating material 20 made of urethane resin or the like. Moreover, four holes are bored in the flat part 11b of the extruded pipe 11, and an outwardly protruding cylindrical part 13 for connecting a branch pipe is integrally formed on the circumferential surface of each hole. An expanded cylindrical portion 14 is formed at the tip of the outwardly protruding cylindrical portion 13 . The outwardly projecting cylindrical portion 13 is formed as follows. That is, after bulging the flat part 11b to form a cylindrical bulge with a closed tip, a hole is made in the center of the cylindrical bulge, excluding the peripheral edge, in the tip closing wall. Then, by burring, the remaining portion of the tip closing wall around the hole is bent outward so as to be flush with the circumferential wall of the cylindrical bulging portion, thereby forming the bulging portion into an outwardly protruding cylindrical portion for connecting a branch pipe. . After that, the distal end of the outwardly protruding cylindrical portion 13 is enlarged, and the enlarged cylindrical portion 1 is
form 4. In this way, the main pipe 10 is made. The outwardly protruding cylindrical portion 13 is also formed by the following method. That is, first, a hole is made in the flat part 11b, and then the part around the hole is burred and bent outward to form the outwardly protruding cylindrical part 13 for connecting the branch pipe.
form. Thereafter, the expanded tube portion 14 is formed in the same manner as described above. Further, a throttle body mounting flange 21 made of an aluminum casting is fixed to the open end of the main pipe 10. A throttle body having a built-in throttle valve (not shown) is attached to the throttle body attachment flange 21, and an air supply pipe from an air cleaner is connected to the throttle body.

Each branch pipe 30 is formed by bending an extruded aluminum pipe with a double-walled structure. That is, the branch pipe 30 consists of an inner wall 31, an outer wall 32, and a radial connecting wall 33 that connects both walls 31 and 32, and a plurality of hollow parts 34 are formed between both walls 31 and 32. be. The inside of the inner wall 31 is made into an air passage 35, and the inner wall 31
serves as a partition wall that separates the air passage 35 and the hollow portion 34. The hollow portion 34 is filled with a heat-retaining heat insulating material 36 made of urethane resin or the like. One end of the branch pipe 30 is inserted into the expanded cylindrical portion 14 of the outwardly projecting cylindrical portion 13 and brazed. Also, 4
The tip of the main branch pipe 30 is connected to a mounting flange 37 for attachment to the cylinder head. The mounting flange is made of aluminum casting, has a horizontal rectangular shape, and has four holes (not shown).
, a curved protruding cylindrical portion 38 for connecting a branch pipe integrally provided around the hole, and an injector insertion port 3
9. An expanded cylindrical portion 40 is provided at the tip of the protruding cylindrical portion 38 . And each branch pipe 30
is connected to the cylinder head of the engine body via this flange 37.

FIG. 4 shows a modification of the main pipe in the intake manifold of this invention. In FIG. 4, the extruded pipe 41 constituting the main pipe is the air passage 4.
A hollow part 44 is provided only on the lower side of 2 through a partition wall 43.
is provided along the entire length. The hollow portion 44 is filled with a heat insulating material 45 such as urethane resin.

In the above-mentioned embodiment and the modification of the main pipe, the hollow parts 18 and 44 of the main pipe are formed, and the inside thereof is filled with the heat insulating materials 20 and 45, but it is not necessary to have such a structure. do not have.

Effects of the Invention According to the intake manifold of this invention, since its inner surface is smooth compared to conventional intake manifolds made entirely of cast parts, air resistance is reduced and intake efficiency is improved. Furthermore, since both the main pipe and the branch pipe are made of bent and stretched material, there is no need for finishing work as with conventional cast products. Furthermore, it becomes possible to achieve weight reduction compared to conventional cast products.

Furthermore, since the temperature inside the branch pipe of the intake manifold can be maintained at an appropriate temperature, it is possible to prevent the temperature inside the branch pipe from becoming too high or too low. Therefore, even if the outside temperature becomes too low, the temperature inside the air passage will not drop to an extreme level, and as a result, the fuel will be vaporized and atomized evenly, especially during startup, and the cylinder will continue to operate normally. combustion occurs. Moreover, the amount of air sent to the engine body does not become too large. Conversely, even if the outside temperature becomes too high, the temperature inside the air passage does not rise excessively, and as a result, the amount of air sent to the engine body does not become too small.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway plan view showing an embodiment of this invention, Fig. 2 is a sectional view taken along the - line in Fig. 1, and Fig. 3 is an enlarged sectional view taken along the - line in Fig. 1. FIG. 4 is a cross-sectional view showing a modification of the main pipe. 10... Main pipe, 30... Branch pipe, 31... Inner wall, 32... Outer wall, 33... Connecting wall, 34... Hollow part, 35... Air passage, 36... Heat insulation material.

Claims (1)

[Scope of utility model registration request] It consists of a main pipe 10 made of aluminum wrought material with one end open and the other end closed, and a plurality of branch pipes 30 made of aluminum wrought material each one end of which is connected to the main pipe 10. 31, an outer wall 32, and a radial connecting wall 33 connecting both walls 31, 32, and a plurality of hollow parts 34 are formed between both walls 31, 32,
The intake manifold has an air passage 35 inside the inner wall 31, and a hollow part 34 filled with a heat insulating material 36.