JPH0477131B2 - - Google Patents

Description

[Detailed description of the invention] A. Purpose of the invention [Industrial application field] The present invention provides, for example, a V-type horizontal engine, etc.
This relates to an exhaust system in which exhaust inlet pipes extending from the exhaust ports of the front and rear cylinders are joined at a rear gathering part and guided to a discharge pipe.

[Conventional technology]

Generally, an exhaust system is often used in which the above-mentioned exhaust gas introduction pipes are assembled so as to substantially face each other, and the combined exhaust gas is discharged to a discharge pipe.

[Problem that the invention seeks to solve]

However, when configured as above, the front cylinder C
The length of the exhaust pipe 1 from the rear cylinder C2 to the collecting part is much longer than that from the rear cylinder C2.

As a result, due to combustion in the engine, the exhaust pulsation existing in the exhaust pipe causes a phase shift in the collecting portion, forming a unique pulsation waveform. As a result, it becomes very difficult to muffle the low-frequency noise generated by the engine's explosion pulse due to the disturbance in the exhaust pulsation, which in turn creates a negative impact on the interior of the vehicle as muffled noise.

Also, the back pressure of the internal combustion engine may increase, resulting in a loss of horsepower.

The present invention aims to solve the above problems.

B. Structure of the invention [Means for solving the problems] The present invention provides front and rear cylinders C of a V-type horizontal internal combustion engine.
1. In an exhaust system in which exhaust inlet pipes 1 and 2 extending from exhaust ports P1 and P2 of C2 are brought together at the rear and the combined exhaust is guided to an outlet pipe 3, the exhaust inlet pipe 1 extending from the front cylinder C1 is The exhaust outlet pipe 3 is disposed approximately on the extension, and the exhaust introduction pipe 2 extending from the rear cylinder C2 is made into a blind pipe and extended toward the front cylinder C1 along the introduction pipe 1. The exhaust ports P1 and P2 of the exhaust ports P1 and P2 are connected to each other by the merging holes 4 ₁ and 4n at positions of equal length L, and a plurality of merging holes are distributed and provided between the merging holes 4 _{1 and} 4n. This is an exhaust system for an internal combustion engine.

[Effect]

With the above configuration, it is easily possible to make the length L of the front introduction pipe 1 to the merging hole 4 ₁ equal to the length L of the rear introduction pipe 2 to the merging hole 4 n. A necessary number of merging holes can be provided in a distributed manner between the pipes 1 and 2 between the merging holes 4 ₁ and 4n to allow smooth merging.

〔Example〕

In FIG. 1, an extension part 22 of the introduction pipe 2 is provided close to and parallel to the introduction pipe 1, and a merging hole 4 ₁ is provided in the parallel facing part.
This is an example in which 4n is provided in a tubular shape.

Figure 2 shows parallel facing parts 1b and 2b of introduction pipes 1 and 2.
Example of flattening and polymerizing and welding as shown in Figure 3, Figure 4
Figures 1 to 6 show an example in which the parallel facing portions of the introduction pipes 1 and 2 have a gutter-shaped cross section, are overlapped via a partition plate 5, and the partition plate is provided with merging holes ₄₁ to 4n. The confluence part is constructed independently as a gathering member, and the pipes 1, 2,
It has a structure in which 3 are connected. In FIG. 6, the partition plate 5 is made into a corrugated shape, and the part 6 formed by the recess 5a has a bench lily effect.

The merging hole can be of any shape, such as circular, square, rectangular, or stabbing hole. 2a shows the blind lid of the introduction tube 2.

C. Effects of the Invention With the above configuration, the lengths L of both the pipes 1 and 2 can be easily made equal without being restricted by the layout of the exhaust system, and the exhaust flows of the introduction pipes 1 and 2 interfere with each other. This has the effect of eliminating the various drawbacks described in the section on problems above.

[Brief explanation of the drawing]

1, 2, 4, and 6 are vertical cross-sectional views of embodiments of the present invention, FIG.
Each central cross-section of the figure. C1...front cylinder, C2...rear cylinder, P1,
P2...Exhaust port, 1, 2...Introduction pipe, 2a...
...Blind cover of inlet pipe 2, 3...Discharge pipe, 1b, 2b...
...Overlapping part, 5... Overlapping partition plate, 4 ₁ to 4n... Merging hole, L... Pipe length.

Claims (1)

[Scope of Claims] 1. In an exhaust system in which exhaust inlet pipes extending from exhaust ports of front and rear cylinders of a V-type horizontal internal combustion engine are integrated at the rear and the combined exhaust is guided to an outlet pipe, an exhaust system extending from a front cylinder An exhaust outlet pipe is placed approximately on the extension of the exhaust inlet pipe to be used, and the exhaust inlet pipe extending from the rear cylinder is made into a blind pipe and extended toward the front cylinder along the inlet pipe. An exhaust system for an internal combustion engine, characterized in that a plurality of merging holes are provided in communication with each other through merging holes at positions of equal length from an exhaust port, and are distributed between the merging holes.