JPS6050215A - Exhaust manifold device in car engine - Google Patents

Abstract

PURPOSE:To prevent the occurrence of relative displacement deformation attributable to a heat distortion before it happens, by making up a part of at least one side of front and rear exhaust pipes leading to each of front and rear exhaust manifolds in a horizontal V-shape multicylinder engine for vehicles, with an expansive flexible pipe, while letting both pipes gather in an exhaust collector chamber. CONSTITUTION:A front exhaust manifold 13 and a rear exhaust manifold 15 are connected to an exhaust port opened to a front cylinder block 4 and a rear cylinder block 2 each. Each front end of a front exhaust pipe 14 and a rear exhaust pipe 16 is connected to both these exhaust manifolds 13 and 15, while both exhaust pipes 14 and 16 extend rearward and connected to an exhaust collector pipe 18. And, a part of the exhaust pipe 16 is made up of an expansive flixible pipe 17.

Description

Detailed Description of the Invention The present invention is applicable to a vehicle in which a front engine block and a rear engine block are arranged along the longitudinal direction of the vehicle, and a crankshaft is arranged in a direction perpendicular to the longitudinal direction of the vehicle. This invention relates to an exhaust pipe device for a horizontal multi-cylinder engine.

In the multi-cylinder engine, both the front exhaust pipe connected to the front exhaust manifold fixed to the exhaust boat of the front engine block and the rear exhaust pipe connected to the rear exhaust manifold fixed to the exhaust boat of the rear engine block are connected to the vehicle. In an exhaust pipe system in which the exhaust pipes are extended rearward and communicated with the exhaust gas collection chamber, the lengths of the front and rear exhaust pipes and their arrangement are different, so it is difficult to heat and cool them. This repetition caused thermal strain between them, which caused the front and rear exhaust pipes to elongate and deform.

SUMMARY OF THE INVENTION An object of the present invention is to provide an exhaust pipe device for a vehicle engine, which has a simple configuration and is capable of effectively absorbing the thermal strain and eliminating the problems described above.

According to the present invention, in order to achieve the above object, at least one of the front exhaust pipe connected to the front exhaust manifold fixed to the front engine block and the rear exhaust pipe connected to the rear exhaust manifold fixed to the rear engine block is provided. The front and rear exhaust pipes are both extended toward the rear of the vehicle and collected in an exhaust gas collection chamber.

An embodiment of the present invention will be described below with reference to the drawings.

A V-type multi-cylinder engine E for a vehicle includes a front engine block 1 that slopes toward the front of the vehicle, a rear engine block 2 that slopes toward the rear of the vehicle, and these engine blocks 1 and 2 are integrally connected. and a crank case 3. The front engine block 1 includes a front cylinder block 4, a front cylinder head 5 that is integrally connected to the upper surface of the front cylinder block 4, and a front head cover 6 that covers the upper surface of the front cylinder block 4. It has a rear cylinder block 7, a rear cylinder head 8 that is integrally coupled to the upper surface of the rear cylinder block 7, and a rear head cover 9 that covers the upper surface of the rear cylinder block 7.

Pistons 10. are located in the cylinder bores of the front and rear cylinder blocks 4, 7, respectively. ．． 102 are slidably engaged with the pistons 101 .

10□ is connected to the crankshaft 12 via connecting rods 111 and 112. The crankshaft 12 is rotatably supported by the crankcase 3 orthogonal to the longitudinal direction of the vehicle.

A front exhaust manifold 13 fixed to an exhaust port opened on the front surface of the front engine block 1 includes a front exhaust pipe 1.
The front end of a rear exhaust pipe 16 is connected to a rear exhaust manifold 15 which is fixed to an exhaust port opened on the rear surface of the rear engine block 2. The front exhaust pipe 14 extends downward from the front surface of the engine E and then extends to the rear thereof, and the rear exhaust pipe 16 extends downward from the rear surface of the engine E and then extends to the rear thereof.

The rear end portion of the rear exhaust pipe 16 is constituted by a telescopic flexible pipe 17 such as a bellows pipe. The open rear ends of the front and rear exhaust pipes 14 and 16 are communicated with the inlet of an exhaust gas collection chamber 18, and the outlet of the chamber 18 is further communicated with a flexible main exhaust pipe 19.

The main exhaust pipe 19 communicates with a catalytic converter and an exhaust muffler (not shown).

Next, the operation of the embodiment of the present invention will be explained.

Due to the operation of engine E, front and rear engine blocks 1
, 2 are the front and rear exhaust gases.
After passing through and collecting in the exhaust gas collection chamber 18, it flows to the main exhaust pipe 19.

By the way, since the front and rear engine blocks 1 and 2 are arranged in the longitudinal direction of the vehicle, the lengths and layouts of the front exhaust pipe 14 and the rear exhaust pipe 16 are different. As a result of repeated heating and cooling, thermal strain is generated between them, but this is absorbed by the bending and expansion/contraction of the telescopic flexible pipe 17 that constitutes a part of the rear exhaust pipe 16, and the front and rear parts due to the thermal strain are Relative displacement, deformation, etc. between the exhaust pipes 14 and 16 can be prevented.

In the above embodiment, the front and rear engine blocks 1, 2
We have explained the case where this is applied to a V-type engine arranged in a V-shape along the longitudinal direction, but the front and rear engine blocks 1
, 2 may be a horizontally opposed engine arranged substantially horizontally in the longitudinal direction. In addition, 6- In the above embodiment, a part of the rear exhaust pipe 16 was constructed by the flexible pipe 17 for absorbing thermal strain, but a part of the front exhaust pipe 14 was constructed by the flexible pipe 17. Further, both the front and rear exhaust pipes 14 and 16 may be partially formed by a telescopic flexible pipe 17.

Further, in the embodiment described above, a bellows tube was used as the telescopic flexible tube 17, but it goes without saying that other telescopic flexible tubes may be used.

According to the present invention, as is clear from the following example,
A part of at least one of the front and rear exhaust pipes is constituted by a telescopic flexible pipe such as a bellows pipe.

The rear exhaust pipes are all extended toward the rear of the vehicle, and their open rear ends are gathered into the exhaust collection chamber, so that the thermal strain generated in the front and rear exhaust pipes is absorbed by the expansion and contraction of the flexible pipes. This can be effectively absorbed by bending, and the relative displacement and deformation of the front and rear exhaust pipes caused by the thermal strain can be prevented.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a partially cutaway side view thereof, and FIG. 2 is a view taken along the arrows in FIGS. 1.2°°° Front, rear engine block, 12... Crankshaft, 13.15... Front, rear exhaust manifold, 14.16... Front, rear exhaust pipe, 17... Telescopic flexible Pipe, 18...Exhaust collection room

Claims (1)

[Claims] In a horizontal multi-cylinder engine for a vehicle, in which a front engine block and a rear engine block are arranged along the longitudinal direction of the vehicle, and a crankshaft is arranged in a direction perpendicular to the longitudinal direction of the vehicle, the front A part of at least one of a front exhaust pipe connected to a front exhaust manifold fixed to the rear engine block and a rear exhaust pipe connected to the rear exhaust manifold fixed to the rear engine block is configured by a telescopic flexible pipe, and the front An exhaust pipe device for a vehicle engine, characterized in that the rear exhaust pipes extend toward the rear of the vehicle even when they are tilted, and their open rear ends are collected in an exhaust collection chamber.