JPH0311370Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention relates to an improvement in an exhaust manifold for an engine that connects a turbocharger.

[Technical background and problems of the invention]

In engines, exhaust gas pressure is used to rotate a turbine to pressurize intake air, thereby increasing the filling efficiency of intake air and increasing output. In this case, as shown in FIGS. 3 and 4, a turbocharger C is connected to the cylinder head A of the multi-cylinder engine at the rear end of an exhaust manifold B that collects exhaust gas from each cylinder. Concatenate. Turbocharger C
is large and protrudes to the side of the engine and takes up space, so the dimension L from the center of the engine to the outer end of the turbocharger C must be made as small as possible. For this reason, the lateral dimension 1 of the exhaust manifold B is designed to be minimized, so that the exhaust manifold B is laid out close to the cylinder head A. Then, in addition to the heat of the exhaust gas passing through, the exhaust manifold pipe B is affected by the heat of the cylinder head A, and as it repeatedly cools and warms, deformation occurs due to withdrawal contraction, and the exhaust manifold pipe B and cylinder head A become deformed.
There is an inconvenience that the fastening surface of the exhaust gas may become distorted, causing exhaust gas leakage.

[Purpose of invention]

In view of the above, the object of this invention is to provide an exhaust manifold for an engine that has a degree of freedom in expanding and contracting due to heat, and does not cause deformation of the mounting surface to the cylinder head.

[Structure of the idea]

Hereinafter, the present invention will be described with reference to an embodiment shown in FIGS. 1 and 2.

The figure shows the case of a four-cylinder engine, in which the exhaust manifold 1 is fastened to the side of the cylinder head 2,
They communicate with the exhaust holes of the respective cylinders, are collected at a collecting pipe section 3, and converge at an outlet 4, to which a turbocharger 5 is connected.

By the way, in the present invention, the collecting pipe portion 3 of the exhaust manifold 1 is curved in a vertically corrugated manner, and is connected to the cylinder head 2 at the intermediate portion 6 of the upper and lower corrugations of the collecting pipe portion 3. Attach the mounting bolt 7 that fixes to the cylinder head 2 on the side of the curved recess 3.

However, when the engine is started or stopped, it is heated by the heat of the exhaust gas during operation and cools and warms repeatedly, so this temperature change causes the exhaust manifold 1 to expand and contract repeatedly. Become.

However, due to the curved part of the collecting pipe part 3, when it expands, the collecting pipe part 3 extends in the direction of the peaks of each waveform, and when it contracts, the collecting pipe part 3 contracts in the direction of the troughs of each waveform, resulting in deformation. can be completely avoided. Moreover, since the connection between the collecting pipe portion 3 and the cylinder head 2 is made at the intermediate portion of the upper and lower corrugations, there is little change in the deformation thereof, and the sealing performance can be maintained in the initial state for a long period of time.

Further, since the mounting bolts 7 are attached to the curved concave side of each collecting pipe section 3, the mounting operation when attaching the collecting pipe section 3 to the cylinder head 2 can be carried out extremely easily.

[Effect of idea]

As explained above, this invention is designed to improve the exhaust manifold's collecting pipe, which is connected to the cylinder head of a multi-cylinder engine, collects exhaust gas from each cylinder, and connects to the turbocharger. The parts were curved into upper and lower corrugations, and the collecting pipe was connected to the cylinder head at the middle of the upper and lower corrugations, and mounting bolts were installed on the curved concave sides of each upper and lower corrugations to fix them to the cylinder head. When the exhaust manifold expands and contracts due to temperature changes, the upper and lower corrugated curved sections extend toward the crests or contract toward the troughs, allowing the collecting pipe section to absorb heat as a whole and allow it to escape, while also allowing exhaust gas to escape. can flow smoothly through conduits with low resistance.

Furthermore, since the connection between the collecting pipe section 3 and the cylinder head 2 was made at the middle part of the collecting pipe where there is less deformation, there is less deformation of the clamping surface between the exhaust manifold pipe and the cylinder head, and the initial accuracy can be maintained for a long time. It improves sealing performance and prevents exhaust gas leaks. Furthermore, since the mounting bolts are attached to the curved concave side of each collecting pipe section, the mounting work when attaching the collecting pipe section to the cylinder head can be carried out extremely easily. Incidentally, since the exhaust manifold is made by casting, even if it is curved, it can be done only with a casting mold, and the manufacturing cost will hardly change.

[Brief explanation of drawings]

1 and 2 show an embodiment of the present invention,
Figure 1 is a cross-sectional front view, Figure 2 is a side view, Figures 3 and 4 are conventional examples, and Figure 3 is a cross-sectional front view.
FIG. 4 is a side view. 1...Exhaust manifold, 2...Cylinder head,
3...collecting pipe section, 5...turbocharger.

Claims (1)

[Scope of utility model registration request] In an exhaust manifold that connects to the cylinder head of a multi-cylinder engine, collects the exhaust gas from each cylinder, and connects it to the turbocharger, the collecting pipe portion of the exhaust manifold is curved vertically in a waveform, and each waveform is An exhaust manifold for an engine, characterized in that the intermediate portion of the manifold is connected to the cylinder head, and mounting bolts are attached to the curved portions of each waveform to fix the manifold to the cylinder head.