JPH0337032B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an improvement in an intake system for a turbocharged engine.

(Prior Art) Conventionally, there has been an intake device in which an enlarged chamber is provided in the middle of an intake passage to store intake air (for example, see US Pat. No. 4,183,332). and,
The enlarged chamber is required to have a large capacity in a fuel injection type engine, especially a diesel engine.

(Problem to be Solved by the Invention) However, in automobiles, etc., the installation space for the engine is limited, so if the enlarged chamber is formed and a turbo supercharger is attached, the intake system becomes large. In order to make it more compact, the intake passage is formed with a bend. However, when the intake passage from the turbocharger to the cylinder of the engine is bent and corners are formed, there is a problem in that the charging efficiency decreases and the supercharging effect decreases.
In particular, in a counterflow type engine where the intake port and exhaust port are opened on one side of the engine, the intake passage and exhaust passage are close to each other, so it is possible to secure an enlarged chamber with the required volume and to It has been difficult to obtain a good supercharging effect without obstructing the flow of fuel and to obtain a compact arrangement structure.

The present invention has been made in view of the above, and an object of the present invention is to provide a counterflow type turbocharged engine with a large-volume expansion chamber and to make it more compact without reducing the supercharging effect. do.

(Means for Solving the Problems) In order to achieve the above object, the solving means of the present invention includes a turbo supercharger in the intake passage, and
The assumption is that the engine is a counterflow type multi-cylinder engine in which the intake port and exhaust port are open on the same side. A substantially cylindrical enlarged chamber is provided in the intake passage downstream of the turbocharger, and the enlarged chamber and the turbocharger are arranged vertically, and the direction of the cylindrical axis of the enlarged chamber is aligned with the cylinder. They are arranged almost parallel to the column direction. The enlarged chamber has a first inner circumferential surface having a circular arc shape, an inlet in which an introduction passage for introducing compressed air from the turbocharger opens in a tangential direction of the first inner circumferential surface, and a cylindrical shape extending from the inlet. an arcuate second inner circumferential surface that smoothly continues with the first inner circumferential surface at a position separated from the axial direction; and compressed air diverted from the inlet along the first inner circumferential surface and the second inner circumferential surface. A plurality of outlet ports are provided, each of which has a derivation passage opening in the connection direction of the second inner circumferential surface and supplies the gas to each cylinder.

(Function) Accordingly, in the present invention, compressed air from the turbocharger flows into the expansion chamber from the introduction passage through the inlet in the direction in which the first inner circumferential surface and the first inner circumferential surface are connected. After turning along the second inner circumferential surface that is smoothly continuous with this, it is discharged from the outlet opening in the tangential direction of this second inner circumferential surface to each outlet passage, passes through the intake manifold, and exits each intake port from the intake port. supplied to the cylinder. Therefore, compressed air can be supercharged to each cylinder without causing turbulence or contraction in the flow of compressed air.

Furthermore, in this case, even if it is a counterflow type engine, the expansion chamber and the turbocharger are arranged vertically, and the cylindrical axis direction of the expansion chamber is approximately parallel to the cylinder row direction. , the expansion chamber and the turbocharger can be arranged compactly and without difficulty in terms of layout.

(Example) Examples of the present invention will be described below with reference to the drawings. In FIGS. 1 and 2, 1 is a counterflow type multi-cylinder (4-cylinder) diesel engine;
2 is an intake passage that supplies air to the intake port 3 of each cylinder of the engine 1, and 4 is an exhaust passage that leads out exhaust gas from an exhaust port (not shown) of each cylinder. Note that 6 is a cylinder head, 7 is a head cover, and 8 is a cylinder block.

On the other hand, 9 is a turbo supercharger installed in the middle of the intake passage 2, and 10 is an enlarged turbo supercharger installed in the intake passage 2 downstream of the turbo supercharger 9 and located above the turbo supercharger 9. It is a room. The turbo supercharger 9 uses a turbine 9a driven by exhaust gas flowing down the exhaust passage 4 to rotate a blower 9b to perform supercharging.

The exhaust passage 4 includes an exhaust manifold 4a that curves downward from an exhaust port and collects exhaust gas, and is connected to a turbine 9a of the turbocharger 9, and an exhaust pipe 4b is connected to the outlet of the turbine 9a. ing.

In the intake passage 2, an intake manifold 2a curved upward from the intake port 3 is connected to an enlarged chamber 10, this enlarged chamber 10 is connected to the blower 9b of the turbo supercharger 9, and an air cleaner ( An intake pipe 2b that supplies air from a pipe (not shown) is connected thereto.

The enlarged chamber 10 is formed into a generally cylindrical shape as a whole, and is arranged so that the cylindrical axis direction is substantially parallel to the cylinder row direction, and the central portion of the enlarged chamber 10 is bent toward the cylinder head 6 side. . An introduction passage 11 that introduces compressed air from the outlet of the blower 9b of the turbocharger 9 is connected to the lower part of the center of the expansion chamber 10, while compressed air is supplied to each cylinder on the left and right sides of the expansion chamber 10, respectively. Two outlet passages 12 are connected to each other.

An arc-shaped first inner circumferential surface 10a is formed on the inner surface of the central portion of the enlarged chamber 10 on the cylinder head 6 side.
Furthermore, an inlet 10b is provided below this central portion, through which an introduction passage 11 opens, through which compressed air from the turbocharger 9 is introduced from the tangential direction of the first inner circumferential surface 10a. Further, the inner surface of the central portion opposite to the cylinder head 6 protrudes inward,
A dividing portion 10c is formed to divide the compressed air flowing along the first inner circumferential surface 10a to the left and right, and on the left and right sides of the dividing portion 10c, the first inner circumferential Surface 10a
A second inner circumferential surface 10d having a circular arc shape and smoothly continuous with each other is formed. Further, below the cylinder head side on both sides of the enlarged chamber 10,
Four outlet ports 10e are provided, each having an outlet passage 12 for discharging the compressed air in the connection direction of the second inner circumferential surface 10d, and the peripheral edge of the outlet port 10e is formed into a curved surface that gradually narrows. .

To explain the operation of the above embodiment, compressed air from the turbocharger 9 is introduced into the introduction passage 1 from below on the opposite side of the cylinder head 6 to the expansion chamber 10.
1 flows in the connection direction of the first inner circumferential surface 10a through the inlet 10b, turns upward along the first inner circumferential surface 10a, and then is divided to the left and right at the flow dividing portion 10c on the opposite side from the cylinder head 6. At the same time, the outlet 10e turns downward along the second inner circumferential surface 10d and opens in the connection direction of the second inner circumferential surface 10d.
The air is discharged from the air into each outlet passage 12, and is supplied to each cylinder from the intake port 3 via the intake manifold 2a.

The present invention is not limited to the structure of the above embodiment, but includes various modifications. That is, in the embodiment described above, the central portion of the enlarged chamber 10 is formed close to the cylinder head 6 side, so that the compressed air can be divided to the left and right well, and the turbocharger 9 is disposed close to the cylinder head 6 side. However, the central portion may be formed in the same manner as the left and right portions, and the enlarged chamber 10 may have a completely cylindrical shape, and the connection position of the turbocharger 9 is not limited to the central portion.

Further, in the above embodiment, the turbocharger 9 is arranged below and the expansion chamber 10 is arranged above, whereas
Although this arrangement may be reversed, it is preferable to arrange the enlargement chamber 10 upward as in the above embodiment from the standpoint of layout based on the relationship with other auxiliary machines. Further, the enlarged chamber 10 and the intake manifold 2a may be formed integrally or may be divided vertically or horizontally depending on the manufacturing thereof.

(Effects of the Invention) As explained above, according to the present invention, in a counterflow type turbocharged engine,
The cylindrical enlarged chamber provided in the intake passage on the downstream side of the turbocharger has a first inner circumferential surface and a second inner circumferential surface that are smoothly continuous, and has a tangential direction from the inlet to the first inner circumferential surface. Compressed air is introduced into the cylinder, diverted along the first and second inner circumferential surfaces, and discharged from the outlet in the tangential direction of the second inner circumferential surface to be supplied to each cylinder. It is possible to prevent the intake air amount from decreasing and to fully exhibit the supercharging effect without causing turbulence or contraction in the flow of air. Furthermore, by vertically arranging the expansion chamber and the turbocharger and arranging the cylindrical axis of the expansion chamber parallel to the cylinder row direction, the expansion chamber and the turbocharger can be arranged compactly, and an engine with a good layout can be obtained. It has the advantage of being able to

[Brief explanation of the drawing]

The drawings illustrate one embodiment of the present invention, with FIG. 1 being a plan view and FIG. 2 being a sectional view taken along the line - in FIG. 1. 1... Diesel engine, 2... Intake passage,
3... Intake port, 4... Exhaust passage, 9... Turbo supercharger, 10... Expansion chamber, 10a... First inner peripheral surface, 10b... Inflow port, 10c... Diversion section, 10
d... Second inner peripheral surface, 10e... Outlet, 11...
Introductory passageway, 12... Leading-out passageway.

Claims (1)

[Claims] 1. A turbo supercharger is provided in the intake passage, and
In a counterflow type multi-cylinder engine in which an intake port and an exhaust port open on the same side, a substantially cylindrical enlarged chamber is provided in the intake passage downstream of the turbocharger, and the enlarged chamber and the turbocharger are connected to each other. are arranged above and below, and the enlarged chamber is arranged so that its cylinder axis direction is substantially parallel to the direction of the cylinder row, and the enlarged chamber has an arcuate first inner circumferential surface; The first
an inlet in which an introduction passage for introducing compressed air from the turbocharger opens in a tangential direction of the inner circumferential surface; and an inlet that is smoothly continuous with the first inner circumferential surface at a position distant from the inlet in the cylinder axis direction. An arc-shaped second inner circumferential surface and compressed air diverted from the inlet to the first inner circumferential surface and the second inner circumferential surface are discharged in a tangential direction of the second inner circumferential surface and supplied to each cylinder. An intake system for a turbocharged engine, characterized in that each outlet passage has a plurality of outlet openings.