JPS5813082Y2 - engine intake system - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement in an engine intake system in which independent low-load and high-load intake passages open into the combustion chamber through a single intake hole. .

Conventionally, an engine intake system in which two intake passages, one for low load and one for high load, are independently opened in the combustion chamber of the engine, a so-called multiple intake system (for example, Japanese Patent Laid-Open No. 47-1
See Publication No. 504.

) is generally well known.

This dual intake system uses only the small-diameter low-load intake passage during low to medium loads, including idling, to increase the flow velocity of the air-fuel mixture and promote fuel vaporization and atomization. The air-fuel mixture is also supplied from the air intake passage to improve output.

In the engine equipped with the above-mentioned multiple intake system, compared to the engine equipped with the conventional intake system consisting of a single intake passage,
In the combustion chamber by promoting vaporization and atomization of fuel at low loads, or in combination with a directional port (an intake port that allows intake air to flow in from a tangential direction to the cylinder and generates a swirl within the cylinder). It has various advantages such as improving combustion efficiency by strengthening the swirl.

Therefore, as an example of the above-mentioned multiple intake system, conventionally, an intake manifold is provided in which independent low-load and high-load intake pipes are formed, and the intake passage provided in the cylinder head is connected to the connection part with the intake manifold. A separation wall is cast at the same time as the cylinder head to bisect the cross section of the intake passage to a position a set distance away from the intake valve installed in the intake hole, and a separation wall continues from this separation wall to just above the intake valve. The intake passage is separated into low-load and high-load intake ports by a partition plate inserted from the intake hole so as to cross the intake passage like a chord. One in which load intake pipes are connected (see, for example, Japanese Utility Model Application No. 53-53208).

) has been proposed. However, in the above-mentioned proposed device, a partition member is inserted from the intake hole so as to cross the intake passage like a string to directly above the intake valve. In order to fix the partition member, for example, the partition member is made of a thin iron plate or aluminum plate, a fitting groove is provided in the cylinder head, and an insertion portion to be inserted into the fitting groove is provided on the partition member, and the partition member is inserted. The part is press-fitted into the fitting groove of the cylinder head, while the partition member is held by the intake valve seat, and since the contact area for fixing the cylinder head and the partition member is small, the partition The fixing force of the member is weak, and there is a risk that it may shift due to vibration, thermal deformation, etc. and come into contact with the intake valve and be damaged.

The present invention solves this problem, and by increasing the contact area for fixing the cylinder head and the partition member, the fixing force of the partition member is strengthened and damage to the partition member is prevented. It is.

Hereinafter, the present invention will be explained in detail with reference to embodiments shown in the drawings.

In Figures 1 to 3, 1 is a vaporizer (not shown)
Intake manifold connected to 2, cylinder head 3
The upstream side thereof is connected to the intake manifold 1, and the downstream side opens to a combustion chamber 5 formed in the cylinder head 3 through an intake hole 4.

The intake manifold 1 is divided into two by a partition wall 6 formed within the intake manifold 1, and a small-diameter low-load intake pipe 7 and a large-diameter high-load intake pipe 8 are formed, respectively. The upstream end of 8 is equipped with a low-load carburetor (not shown) and a high-load carburetor (not shown).

Further, the cylindrical space 2 provided in the cylinder head 3 is
An upper cylindrical space 2b that extends from a connection part 2a with the intake manifold 1 to a position a set distance away from the intake valve 9 attached to the intake hole 4, and a lower part that extends continuously from the upper cylindrical space 2b to just above the intake valve 9. It is constituted by a cylindrical space 2C.

The above-mentioned upper cylindrical space 2b is divided into two by the separation wall 10, and is defined into a small-diameter upper low-load intake port 11 and a large-diameter upper high-load intake port 12.
The downstream end surface of the partition wall 6 is connected to the upstream end surface 10a of the partition wall 6, and the low load and high load intake pipes 7 are connected to the upper low load and upper high load intake ports 11 and 12, respectively. , 8 are communicated.

Reference numeral 13 denotes a cylindrical member installed in the lower cylindrical space 2C of the cylinder head 3, and this cylindrical member 13 is connected to a partition member 14 that is continuous with the separation wall 10 and crosses the lower cylindrical space 2C like a chord. Which partition member 1 is integrally formed?
The lower low-load and lower high-load intake balls 15.16 and the upper low-load and high-load intake balls 1 to 11.12 are connected to each other, respectively. It has a load phase open Ll 17j8.

The above-mentioned low load and high load 1 intake trachea 7, 8, upper low load and upper high load intake port-h 11,1
2, and lower low load and lower high load intake ports 15
．． 16 constitutes a dual intake system which is provided with an independent small-diameter low-load intake passage 19 and a large-diameter high-load intake passage 20, each of which opens into the combustion chamber 5 through a single intake hole 4. ing.

Reference numeral 21 denotes an intake valve 9 that opens and closes the intake hole 4 at a predetermined timing.
A valve guide 22 that slidably supports the valve shaft portion 9a of the
is a valve seat attached to the intake hole 4.

As shown in FIG. 4, the cylindrical member 13 has a cylindrical shape as a whole, and has a partition member 14 formed integrally with the cylindrical member 13 at the time of casting on the inner peripheral side.

The partition member 14 has a central portion 14a curved in a semicircular shape so as to surround the valve shaft portion 9a of the intake valve 9;
Side portions 14 projecting in a chord shape on both sides of this central portion 14a.
bj4C, and has an end face 10b (hereinafter referred to as a downstream end face) of the separation wall 10 facing the intake hole 4.

) is formed to have almost the same shape as the downstream end surface 10b of the separation wall 10, and the lower end edge 14d
e is formed in a chevron shape along the valve head 9b of the umbrella-shaped intake valve 9.

The outer peripheral surface 13a of the cylindrical member 13 is in contact with the cylinder head 3 as shown in FIG. 1, except for the low-load and high-load phase openings 117 and 18.

For example, such a cylindrical member 13 may be installed by being integrally cast when casting an aluminum cylinder head, or the partition member 14 may be connected to the partition wall 10 before the intake valve seat 22 is press-fitted. Insert from hole 4 and separate wall 1
After the abutting end surface 14d is aligned and abutted with the downstream end surface 10b of the intake valve 4, the intake valve seat 22 is fitted and fixed to the peripheral wall of the intake hole 4.

Therefore, the outer peripheral surface 13a of the cylindrical member 13, which is formed integrally with the partition member 14, except for the low-load and high-load openings 17 and 18, is in contact with the cylinder head 3.
As a result, the contact area of the partition member 14 with the cylinder head 3 becomes larger, the fixing force of the partition member 14 can be strengthened, and shaking and damage of the partition member 14 can be prevented.

Further, the cylindrical member 13 and the partition member 14 are cast and formed from the same aluminum alloy as the cylinder head 3,
If the cylindrical member 13 is integrally cast during casting of the cylinder head 3, the fixing force between the cylindrical member 13 and the cylinder head 3 can be further strengthened.

As explained above, according to the present invention, there is an intake manifold in which independent low-load and high-load intake pipes are formed, and a set distance from the connection part of the intake manifold to the intake valve installed in the intake hole. A one-L cylindrical space extending to a distant position is divided into two by a separation wall to form an upper low-load intake port and an upper high-load intake port that communicate with the low-load intake pipe and the high-load intake pipe, respectively. a cylinder head that forms a lower cylindrical space that extends directly above the intake valve and is continuous with the upper cylindrical space; and a partition member that is continuous with the separation wall and crosses the lower cylindrical space like a chord; and has low-load and high-load openings that communicate the lower low-load and lower high-load intake ports separated by the partition member with the upper low-load and upper high-load intake ports, respectively. and a cylindrical member installed in the lower cylindrical space of the cylinder head, and the outer peripheral surface of the cylindrical member excluding the low-load and high-load openings is in contact with the cylinder head. Since a sufficient contact area with the head can be secured and the fixing force can be strengthened, shaking and damage of the partition member can be prevented.

[Brief explanation of the drawing]

The drawings illustrate embodiments of the present invention, with FIG. 1 being a schematic explanatory diagram showing the overall configuration, and FIG. 2 being a sectional view taken along line II-II in FIG.
3 is a view taken in the direction of arrow A in FIG. 2, and FIG. 4 is a perspective view of the cylindrical member shown in FIG. 1. 1... Intake manifold, 2... Cylindrical space, 2b... Upper cylindrical space, 2C...
... lower cylindrical space, 3 ... cylinder head, 4 ... intake hole, 5 ... combustion chamber, 6 ...
...Bulkhead, 7...Intake pipe for low load, 8.
...Intake pipe for high load, 9...Intake valve, 1
0...Separation wall, 11...-H part low load intake port, 12...Top high load intake port 1-113...Cylinder Part, 14...
Partition member, 15...Lower low load intake port,
16...Lower high load intake port 1~. 17...
...Low load opening, 18...High load opening, 19...Low load intake passage, 20...
・Intake passage for high loads.

Claims (1)

[Scope of utility model registration request] An intake manifold in which independent low-load and high-load intake pipes are formed, and an upper cylindrical space that extends from the connection with the intake manifold to a set distance from the intake valve attached to the intake hole. The upper part is divided into two parts by the cylindrical space, and an upper part for low load and -1 part for high load are respectively communicated with the intake pipe for low load and for high load. A cylinder head that forms a lower cylindrical space that extends directly above the cylinder head, and a lower lower cylinder that is formed integrally with a partition member that is continuous with the separation wall and crosses the lower cylindrical space like a string, and that is separated by the partition member. It has low-load and high-load openings that communicate the load and lower high-load intake ports with the upper low-load and upper high-load intake ports, respectively, and is installed in the lower cylindrical space of the cylinder head. An intake device for an engine, characterized in that it is provided with a cylindrical member.