JP2002285923A - Sealing structure for intake device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify assemblage of an intake device for an internal combustion engine. SOLUTION: In this intake device for a multiple cylinder internal combustion engine, a carburetor 1 for respectively feeding air-fuel mixture to plural cylinders is contained and fixed in a common air cleaner case 7, disposed to be close to the upper part of a cylinder head 5; and an inlet end surface of an intake port 6 of the cylinder head 5, an outlet end surface of an inlet manifold 4 upstream of the intake port 6, and the air cleaner case 7 are sealed with the same seal member 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a seal structure for an intake device of an internal combustion engine.

[0002]

2. Description of the Related Art A conventional air cleaner case having a suction device (carburetor) inside an air cleaner case is disclosed in, for example, U.S. Pat.
There was one disclosed in JP-A-9-41302. This is because the first row of cylinder bodies and the second row of cylinder bodies are arranged in a V-shape, and the common vaporizer storage case arranged in a space formed between the cylinder bodies has the above-mentioned structure. A plurality of carburetors for supplying the air-fuel mixture respectively to the first and second rows of cylinder bodies are accommodated and fixed, and the inlets of the carburetors are directly opened, and the carburetors are further opened. This is a V-type multi-cylinder internal combustion engine that communicates the inside of a storage case with the atmosphere via an air cleaner.

[0003]

The air cleaner having the conventional intake device (carburetor) inside has a structure integrally formed with a connecting member connected to the internal combustion engine, thereby holding and sealing the air cleaner. However, since it is difficult to integrally form the connecting member and the air cleaner that connects the intake device and the internal combustion engine, both in terms of material and manufacturing method, the connecting member and the air cleaner are separately formed and assembled in advance. Had to be kept.

[0004]

According to the first aspect of the present invention, a carburetor for supplying an air-fuel mixture to a cylinder is provided above a cylinder head. In the intake device for an internal combustion engine, which is housed and fixed in an air cleaner case arranged in a predetermined manner, an inlet end face of an intake port of the cylinder head, an outlet end face of an inlet manifold upstream of the intake port, and the air cleaner case. And a seal structure of the intake device, wherein the seal structure is sealed by the same seal member. Therefore, according to the first aspect of the present invention, the sealing structure is simplified and the number of assembling steps is reduced.

[0005] The invention according to claim 2 is the invention according to claim 1.
In the invention described above, a seal member formed of an elastic body is sandwiched between an inlet end face of the intake port and an outlet end face of the inlet manifold, and the air cleaner case is sealed by a lip formed on an outer periphery of the seal member. It is characterized by that.

As described above, according to the second aspect of the present invention, a sealing member is interposed between the inlet manifold and the intake port, which require a high degree of sealing, and a high degree of sealing is provided between the inlet manifold and the intake port. When the air cleaner case is sealed with the lip portion of the seal member, the assemblability is further improved by not requiring the ease of use and the position accuracy relatively gently.

[0007]

FIG. 1 is a longitudinal sectional view showing an intake device of an internal combustion engine to which an embodiment of the present invention is applied, together with an intake port of a cylinder head.

The internal combustion engine to which this embodiment is applied is a V-type 5
As shown in the figure, a carburetor 1 for supplying an air / fuel mixture to each cylinder is housed and fixed in a common air cleaner case 7 disposed close to and above a cylinder head 5. You. That is, the combustion air from which foreign substances such as dust, moisture, and oil have been removed by an air cleaner (not shown) passes through the air funnel 2, the throttle valve 3, and the inlet manifold 4 from inside the air cleaner case 7, and further passes through the intake port 6 of the cylinder head 5. Is supplied to a cylinder (not shown). In the meantime, fuel is injected from the fuel injection device 8 to become an air-fuel mixture.

In this embodiment, a gasket 9 made of an elastic material is sandwiched between the inlet end face of the intake port 6 of the cylinder head 5 and the outlet end face of the inlet manifold 4 upstream thereof as a seal member.

FIG. 2 is a view showing a gasket 9 used in a row of three cylinders out of five cylinders of the internal combustion engine.
(A) is a plan view, (b) is a sectional view taken along the line BB of (a),
(C) is an enlarged view of the C part of (b). As shown,
The gasket 9 has three cylinders in this row continuously and integrally formed. The gasket 9 is provided with a bolt hole 9b in addition to the intake hole 9a through which the air-fuel mixture is passed. Sealing is performed by fastening the intake port 6 with bolts. 9d between the intake holes 9a
Is thin because there is no need for a seal. An air cleaner case 7 described later is provided on the outer periphery of the gasket 9.
A lip 9c is provided for sealing between the lip 9c.
The same applies to the gaskets used for the remaining two-cylinder rows.

Next, FIG. 3 is a bottom view showing the air cleaner case of the present embodiment. The air cleaner case 7 has an intake hole 7 a and a bolt hole 7 corresponding to the shape of the gasket 9.
b etc. are provided. A wall 7c is provided continuously at a portion corresponding to the outer periphery of the gasket 7, as shown in FIG. 4, which is an enlarged view of an IV section in FIG. 1, and a lip of the gasket 9 is attached to the wall 7c. The sealing is achieved by the contact of 9c. The double diagonal lines in the figure indicate the area where the non-slip rubber 7d is attached.

When assembling, the air cleaner case 7 is placed on the intake port 6 of the cylinder head 5, the gasket 9 is fitted into the hole of the intake hole, the inlet manifold 4 of the carburetor 1 is attached thereto, and the bolt is attached. To conclude. In this case, as shown in FIG. 4, the lip 9 c of the gasket 9 contacts the wall 7 c at the edge of the air cleaner case 7, but there is a gap 10 between the gasket 9 main body and the air cleaner case 7.

FIG. 5 is a sectional view showing an assembled state between intake holes in the same cylinder row. As described above, a non-slip rubber 7d is provided between the intake holes 7a of the air cleaner case 7.
Is affixed to the thin portion 9 of the gasket 9
d and the cylinder head 5, the bolt 11
There is no danger of shifting after fixing. Moreover, since the space between the intake holes 7a is connected by the members of the air cleaner case 7, the rigidity of the entire air cleaner case 7 is also maintained.

According to the present embodiment, the inlet manifold 4 of the carburetor 1 and the intake port 6 of the cylinder head 5
And the air cleaner case 7 are sealed by the same seal member (gasket 9), so that the structure is simplified and the number of assembling steps is reduced. That is, a gasket 9 is sandwiched between the inlet manifold 4 and the intake port 6 which require a high degree of sealing performance, and the gasket 9 is fastened with bolts. By assembling the air cleaner case 7 with the lip 9c of the gasket 9 which does not require a high degree of sealing property between the ports 6, the assembling property can be improved.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an intake device of an internal combustion engine to which an embodiment of the present invention is applied, together with an intake port of a cylinder head.

FIG. 2 is a plan view and a sectional view showing a gasket used as a seal member of the embodiment.

FIG. 3 is a bottom view showing the air cleaner case of the embodiment.

FIG. 4 is an enlarged view showing an IV section in FIG. 1;

FIG. 5 is a sectional view showing an assembled state between intake holes in the same cylinder row.

[Explanation of symbols]

1: vaporizer, 2: air funnel, 3: throttle valve,
4 ... Inlet manifold, 5 ... Cylinder head,
6 ... intake port, 7 ... air cleaner case, 7a ... intake hole, 7b ... bolt hole, 7c ... wall, 7d ... non-slip rubber, 8 ... fuel injection device, 9 ... gasket, 9a ... intake hole, 9b ... bolt hole, 9c: lip, 9d: thin part, 10
... clearance, 11 ... bolts.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F16J 15/10 F02M 35/10 102B 102J F-term (Reference) 3J040 AA01 AA11 EA02 FA06 HA03 HA19

Claims (2)

[Claims] 1. An intake device for an internal combustion engine, wherein a carburetor for supplying an air-fuel mixture to a cylinder is housed and fixed in an air cleaner case disposed close to above the cylinder head. A seal structure for an intake device, wherein the inlet end face of the intake port, the outlet end face of the inlet manifold upstream of the intake port, and the air cleaner case are sealed with the same seal member. 2. A seal member formed of an elastic body is sandwiched between an inlet end face of the intake port and an outlet end face of the inlet manifold, and the air cleaner case is sealed by a lip formed on an outer periphery of the seal member. The seal structure for an intake device according to claim 1, wherein: