JPS6231665Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an intake pipe system vibration damping device for an internal combustion engine.

Conventionally, in a so-called V-type internal combustion engine in which cylinder blocks are arranged in a V-shape, a bifurcated branch intake intake pipe is connected between the intake manifolds attached to the left and right cylinder heads, and intake air from the air cleaner is introduced into the same intake manifold. It has a configuration that leads to the intake manifold through a pipe. Since the intake pipe has a simple ring-shaped cross-sectional shape, its rigidity is low, and as a result, vibrations transmitted to the intake manifold through the cylinder head during engine operation cause
The intake pipe resonates between the left and right cylinder heads,
There was also a problem that it became a source of noise.

The present invention has been devised in view of the above, and includes a cylinder block arranged in a V-shape, a cylinder head placed on the upper end surface of the block, an intake manifold attached to each head, and one end opening facing the air cleaner. The intake manifold is provided with an intake introduction pipe whose other end is bifurcated and communicated with each of the intake manifolds, and has a portion with a large diameter and a portion with a small diameter. The intake flow path is formed into a transverse wavy curved shape having a pair of grooves facing each other and recessed along the same groove and toward the inside of the pipe, and connecting the two grooves along the same groove and between the two grooves. In order to divide the tube, a partition wall is formed in the large diameter portion of the pipe, and a strut is formed in the small diameter portion of the pipe, and the thickness of the partition wall and the strut are gradually increased as they approach the outer wall of the intake pipe. According to the present invention, since the surface of the intake pipe has a structure with increased rigidity, vibrations generated on the surface can be suppressed. The practical effect of effectively reducing noise can be obtained. The present invention will be described with reference to the embodiment shown in FIGS. 1 to 4. Reference numerals 1 and 2 are cylinder blocks, 3 and 4 are cylinder heads placed on the upper end surface of the blocks,
Reference numerals 5 and 6 indicate intake manifolds attached to the side wall of the head; reference numeral 7 indicates an intake manifold having an opening 8 at one end for an air cleaner 9 and openings 10 and 11 at the other end branching from the opening 8 at one end in a bifurcated shape. 6, respectively. Reference numeral 12 denotes a partition wall formed integrally with the intake air introduction pipe 7, and reference numeral 13 denotes a column having a circular cross section. Both the partition wall 12 and the column 13 are formed along the flow direction of the intake air. , and the intake pipe is 2 in cross section.
Divided into aisles. 14 is a groove,
Partition walls 12 and pillars 13 are formed along the grooves 14 .

In this embodiment, the intake air introduction pipe 7 is formed to have a wave-shaped cross section with a pair of grooves 14 facing each other and recessed into the pipe 7 along the flow direction of the intake air. In order to divide the intake flow path into two by connecting both the concave grooves and dividing the intake flow path into two, a partition wall is formed in the part where the pipe diameter is large, and a strut is formed in the part where the pipe diameter is small. Also, since the thickness of the support column gradually increases as it approaches the outer wall of the intake pipe, the rigidity of the intake pipe 7 is large, and therefore vibrations are transmitted from the cylinder heads 3 and 4, which are the vibration sources. Also, the vibration of the intake pipe is suppressed, the intake pipe system including the intake manifolds 5, 6 and the introduction pipe 7 can be effectively damped, and engine noise can be greatly reduced.

The strut 13 in the above embodiment had a circular cross section, but as shown in FIG.
In this case, the flow resistance of the intake air can be lowered, and in this case, the strut 13 and the strut 13
It is preferable that the pitch L is smaller than or equal to the pipe diameter W.

6 and 7 show other modified examples of this embodiment, in which 15 is an enlarged part formed as a part of the partition wall 12, and 16 is an enlarged part.
are loopholes bored vertically in the ampulla 15,
The water and oil accumulated in the grooves 14 can be allowed to fall downward through the through holes 16, thereby having the effect of avoiding soiling and corrosion of the intake pipe 7.

[Brief explanation of the drawing]

FIG. 1 is an external perspective view of an embodiment of the present invention;
Fig. 2 is a plan view of the intake pipe as seen from the direction of the arrow in Fig. 1, Fig. 3 is a sectional view taken along the - line in Fig. 2, Fig. 4 is a sectional view taken along the - line in Fig. 2, and Fig. 5. 6 is a plan view similar to FIG. 2 in a modified example of the present embodiment, FIG. 6 is a plan view in yet another modified example, and FIG. 7 is a sectional view taken along the line - in FIG. 6. 5, 6... Intake manifold, 7... Intake introduction pipe, 9... Air cleaner, 12... Partition wall, 13
...Strut, 14...Concave groove.

Claims (1)

[Scope of utility model registration request] A cylinder block arranged in a V-shape, a cylinder head placed on the upper end surface of the block, an intake manifold attached to each head, and an opening at one end facing the air cleaner and an opening at the other end branching into each of the above intake manifolds. A pair of air intake pipes are provided with an air intake introduction pipe that communicates with each other and have a portion with a large diameter and a portion with a small diameter. The pipe is formed into a wavy curved cross-sectional shape having grooves, and a partition wall is provided at the larger diameter portion of the pipe in order to divide the intake flow path into two by connecting both grooves along the groove. An intake pipe system for an internal combustion engine, characterized in that struts are formed in each of the portions where the pipe diameter is small, and the thickness of the partition wall and the struts gradually increase as they approach the outer wall of the intake pipe. Vibration damping device.