JPH04136420A - Intake device of engine - Google Patents

Abstract

PURPOSE:To increase the intake inertial effect by installing a communication chamber surrounded by the passage wall of each independent intake passage on the downstream of the collection part of the independent intake passage which communicates to the intake port of each cylinder and allowing the communication chamber to communicate to each independent intake passage. CONSTITUTION:An intake manifold 10 has four independent intake passages 12, and the upstream parts of the independent intake passages 12 are collected in close state so that a square shaped arrangement is formed on the section, and are formed to a collection part 13, and the upstream edge is connected with a common intake passage. In this case, on the downstream of the collection part 13, a communication chamber 14 which forms a conical space surrounded by the passage wall 12a of each independent intake passage 12 which forms a smooth curved line is formed, and an opened port 15 set close to each independent intake passage 12 is formed on the peripheral wall of the chamber 14. In the chamber 14, a conical valve 16 having a nearly same shape to that of the chamber 14 is installed, and four opened ports 15 are closed all together by upwardly shifting the valve 16 by an actuator installed between the independent intake passages 12, and the communication between the independent intake passages 12 can be cut off.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to an intake passage for an engine.

(Prior art) In the intake manifold of each cylinder engine, the upstream portions of the independent intake passages that communicate with the intake ports of each cylinder are assembled close to each other so that the cross section is a square array (in the case of a 4-cylinder engine). An intake system is known in which the intake manifold is made more compact, the intake resistance is reduced, and the fuel distribution to each cylinder is improved (see Japanese Utility Model Application No. 57-101367).

In addition, conventionally, in automobile engines, negative pressure waves that occur with the start of intake are reflected at the open end of the intake expansion chamber formed by the surge tank on the upstream side of the intake passage, and are returned to the intake port as positive pressure waves. Taking advantage of this, there is a system that increases the filling efficiency of the intake air by the so-called inertia effect of the intake air, in which the positive pressure wave reaches the intake port just before the intake valve closes and forces the intake air into the combustion chamber.

To obtain this intake inertia effect, the intake passage is required to be long in the low engine speed range, and is required to be short in the high engine speed range.

Therefore, for example, in the invention disclosed in Japanese Patent Application Laid-Open No. 62-7922, as shown in FIG.
A long curved first independent intake passage 3 branching from the surge tank 2 and communicating with each cylinder, a volume chamber 4 formed inside the curved part of the first independent intake passage 3, and a volume chamber 4 formed inside the curved portion of the first independent intake passage 3. A short second independent intake passage 5 is provided which communicates with the midway of each first independent intake passage 3, and a control valve 6 for opening and closing the second independent intake passage 5 is provided in each second independent intake passage 5. The control valve 6 is opened and closed according to the operating state of the engine.

In this way, in the low speed range of the engine, by closing the control valve, the first pressure wave of the intake air is long.
The intake inertia effect is obtained through the independent intake passage in the form of being reversed by the surge tank, and in the high engine speed range, by opening the control valve, the pressure wave of the intake air is reduced through the short second independent intake passage. The intake inertia effect is obtained by being reversed in the volume chamber. Moreover, since the upstream ends of the second independent intake passages communicate with each other in the volume chamber, pressure waves from other cylinders act through the volume chamber in the high engine speed range, resulting in intake inertia. There is an advantage that the effect is enhanced and the area where the intake inertia effect can be obtained is expanded.

However, on the other hand, there are cases where the second intake passage becomes a dead volume, where pressure waves are attenuated and the intake inertia effect is weakened.

Further, the number of control valves 5 is equal to the number of cylinders, and these need to be rotated by a single shaft 7 extending parallel to the volume chamber 4.

(Object of the Invention) The present invention provides an engine equipped with an intake manifold, as described above, in which the upstream parts of independent intake passages communicating with the intake ports of each cylinder are gathered together in close proximity to each other to form a gathering part. An object of the present invention is to provide an intake device that can obtain an excellent intake inertia effect without compromising the compactness of the intake manifold and low intake resistance characteristics.

(Structure of the Invention) The present invention provides a communication chamber surrounded by the passage walls of each independent intake passage downstream of a gathering part of the independent intake passages, and an opening in the chamber wall of the communication chamber that communicates with each independent intake passage. In addition to establishing
The communication chamber is characterized in that a substantially conical valve that opens and closes the opening is provided in the communication chamber.

An actuator for actuating the valve is disposed between the independent intake passages.

Further, in the present invention, a communication port is provided in the partition wall between the independent intake passages forming the collective intake passage, and a communication port is provided for communicating the independent intake passages with each other, and a substantially conical valve is provided for opening and closing the communication port. It is characterized by

(Effects of the Invention) According to the present invention, it is possible to obtain an intake inertia effect without sacrificing the compactness of the intake manifold and the low intake resistance characteristics, and also because the communication passage connecting each independent intake passage is extremely short. Since the dead volume becomes smaller and the attenuation of pressure waves can be suppressed, the intake inertia effect is further increased.

Further, according to the present invention, since a means for obtaining an intake inertia effect is provided downstream of the gathering portion where the upstream portions of the independent intake passages are gathered, the propagation path length of the pressure wave for each cylinder is approximately equal. This has the advantage of providing high torque.

Further, according to the present invention, there is an advantage that only one valve that is controlled according to the operating state of the engine is required to obtain the intake inertia effect.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIGS. 1 and 2 show an intake manifold according to a first embodiment of the present invention, and this intake manifold 10 consists of four independent blocks each having a downstream end open at a flange 11 attached to a cylinder head of an engine (not shown). The upstream portions of these independent intake passages 12 are gathered together in close proximity to each other so that the cross section is a regular square array, and form a gathering part 13, and the upstream end thereof is a common part (not shown). Connected to the intake passage.

A communication chamber 14 is formed downstream of the gathering portion 13, and is a conical space surrounded by the passage walls 12a of each of the independent intake passages 12 that form a smooth curve. An opening 15 facing the passage 12 is formed so that the four independent intake passages 12 communicate with each other through the chamber 14. A conical valve 16 that substantially matches the shape of the chamber 14 is movably provided in the chamber 14, and the valve 16 is moved to the position shown in FIG. 1 by an actuator provided between the independent intake passages 12. , the four openings 15 are closed all at once, communication between the independent intake passages 12 is cut off, and the valve 16 is
In the position shown, all four openings 15 are open so that the four independent intake passages 12 communicate with each other through the chambers 14.

That is, in this embodiment, in the low engine speed range, the valve 16 closes the four openings 15, so that the pressure wave of the intake air is reversed through the independent intake passage 12 at the upstream surge tank, and the intake inertia is reversed. In addition, in the high speed range of the engine, when the valve 16 opens the four openings 15, the intake inertia effect is obtained in the form that the pressure wave of the intake air is reversed in the chamber 14 through the openings 15. become. Moreover, in this case, four independent intake passages 12
are in communication with each other through the chamber 14, so in the high rotation range of the engine, pressure waves from other cylinders flow into the chamber 14.
The effect similar to that of the structure shown in FIG. 8 can be obtained with a simpler structure.

Although the shape of the valve 16 is called "conical" in this embodiment, in reality, the part of the valve 16 that closes the opening 15 corresponds to the peripheral wall of the chamber 14, which is formed to minimize intake resistance. It has a smooth streamlined shape.

Next, FIG. 3 is a diagram showing the configuration of an intake manifold according to a second embodiment of the present invention.
Similar to the one in the figure, there are four independent intake passages 12, and the upstream portions of these independent intake passages 12 are assembled in close proximity to each other so that the cross section is a square arrangement to form a gathering part 13. are doing. The independent intake passages 12 are smoothly curved downstream of the gathering part 13 and the distance between the independent intake passages 12 is widened. A communication port 18 is provided in the four independent intake passages 12, and the four independent intake passages 12 are configured to communicate with each other through the communication port 18.

A conical valve 19 that opens and closes this communication port 18 is provided.

The intake manifold 20 in this embodiment has an upstream portion 20 that is flanged to facilitate its assembly.
a and a downstream portion 20b, and the communication port 18 and valve 19 are provided in the upstream portion 20a. A normal diaphragm actuator 21 for operating the valve 19 is disposed in the center of the independent intake passage 12 of the downstream portion 20b, and an operating rod 21a extending from the actuator 21 is connected to a rod 19a extending from the valve 19. , valve 19 is shown in FIG. 4 by actuator 21. The communication port 18 is opened so as to open. Note that even if the intake manifold 20 is not divided into an upstream portion 20a and a downstream portion 20b, it goes without saying that the configuration as in this embodiment is possible.

FIG. 5 is a diagram showing the configuration of an intake manifold according to a third embodiment of the present invention. The intake manifold 30 has almost the same configuration as the intake manifold 20 shown in FIGS. 3 and 4, and has a flange connection. However, in this embodiment, instead of the actuator 21 shown in FIGS. It is integrated with the valve 19 in the portion 30a. That is, the chamber 34 is formed by a diaphragm 32 connected to the rod 19 of the valve 19 and a partition wall 33 formed at the joint end surface of the downstream part 30b and the upstream part 30a.
is formed, and the diaphragm 32 is urged upward in FIG. 4 by the spring 35, so that the valve 19 normally closes the communication port 18, but the inside of the chamber 34 of the actuator 31 is made negative pressure. Then, the diaphragm 32 moves downward in FIG. 4 against the urging force of the spring 35, so that the valve 19 opens the communication port 18.

Although the above embodiments are cases in which the present invention is applied to an in-line four-cylinder engine, the present invention can also be applied to, for example, a V-type six-cylinder engine in which three cylinders are arranged in each of the left and right banks. In that case, as shown in FIG. 6, a gathering portion 13L of the three independent intake passages 12 in the left bank and a gathering portion 13R of the three independent intake passages 12 in the right bank are arranged independently, and each has a conical valve shape. 19, or as shown in FIG.
A conceivable configuration is that R are further gathered together to form a gathering portion 13T, and all six independent intake passages 12 are brought into communication via two conical valves 19.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the configuration of an intake manifold of an in-line four-cylinder engine according to a first embodiment of the present invention, FIG. 2 is a cross-sectional view thereof, and FIGS. FIGS. 6 and 7 are vertical cross-sectional views showing the configuration of intake manifolds according to second and third embodiments of the invention, and FIGS. 8 are vertical sectional views showing the structure of an intake manifold of a conventional engine. 10.20.30...Intake manifold 12...Independent intake passage 13...Collecting part 14...Communication chamber
15... Opening of communication chamber 16.19... Conical valve 17... Partition wall 18... Communication port 21.3
1... Actuator 32... Diaphragm Figure 5

Claims (1)

[Scope of Claims] 1. An engine equipped with an intake manifold for each cylinder engine in which upstream parts of independent intake passages communicating with the intake ports of each cylinder are gathered together in close proximity to each other to form a gathering part, A substantially conical chamber surrounded by the passage walls of each independent intake passage is provided downstream of the gathering part of the independent intake passages, and an opening facing each independent intake passage is provided in the chamber wall of this chamber, and each independent intake passage is provided with an opening facing each independent intake passage. An intake system for an engine, characterized in that the valves communicate with each other through the chamber, and a substantially conical valve for opening and closing the opening is provided in the chamber. 2. The intake system according to claim 1, wherein an actuator for operating the valve is disposed between the independent intake passages. 3. In an engine equipped with an intake manifold for each cylinder engine in which the upstream portions of independent intake passages communicating with the intake ports of each cylinder are gathered together in close proximity to each other to form a gathering part, forming the gathering part as described above. On the partition wall between the above independent intake passages,
An intake system for an engine, characterized in that a communication port is provided for communicating the independent intake passages with each other, and a substantially conical valve is provided for opening and closing the communication port.