JPH0579416A - Intake device for internal combustion engine - Google Patents

Abstract

(57) [Summary] [Object] The present invention relates to an intake device in which an intake pipe is installed inside a surge tank, and an object thereof is to provide an intake device that is not sucked into an intake passage even if a bolt of the installation part falls off. And [Structure] The intake pipe 6 is made of a resin material,
The collared bolt 7 is attached to the flange portion 6 of the intake pipe 6.
It is press-fitted into a to be integrated with it, and this is fastened and fixed to the flange portion 3a of the throttle body 3 which is an intake passage member.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intake system for an internal combustion engine, and more particularly, to an intake pipe member (also called an air horn) connected to an intake passage member extending from an internal combustion engine body such as an intake manifold, in a surge tank. The present invention relates to an intake system for an internal combustion engine that secures the capacity of a surge tank and tries to obtain an inertia supercharging effect in the engine low-medium speed range.

[0002]

2. Description of the Related Art For example, a so-called throttle valve is provided independently in each intake passage corresponding to each cylinder of an internal combustion engine.
In an independent throttle internal combustion engine, normally, an intake pipe and a surge tank are arranged in order on the intake upstream side of a throttle body to which a throttle valve is attached, and these elements are externally fastened to each other by bolts or the like. (Japanese Patent Laid-Open No. 2-61324, etc.).

However, in the case of such an external fastening type intake device, considering the mass production thereof, a certain amount of tool space for assembly is inevitably required,
The capacity of the surge tank is inevitably limited to secure this space, and due to its small capacity, there is a problem that high performance cannot be exhibited over the entire engine rotation range (especially in the low and middle rotation range). there were.

In order to deal with such a problem, for example
In Japanese Patent Laid-Open No. 62-76243, an intake pipe (extension pipe) is fastened to an intake passage (branch pipe) inside the surge tank to open the end of the intake pipe in the surge tank, and then the surge tank is capped. An intake device has been proposed in which the surge tank capacity is secured without shortening the intake passage length.

[0005]

By the way, in the intake passage for connecting the intake passage member and the intake pipe in the surge tank as described above, the connection between the parts is performed by the assembling workability and the matching after the assembling. From the viewpoint of the above, it is preferable that the intake pipe is detachably attached to the intake passage member, and generally, the intake pipe is connected to the intake passage member inside the surge tank by a fastening bolt. ..

However, in the case of so-called internal fastening in which the two parts are connected by bolts inside the surge tank, the fastening bolt may come off the intake pipe due to vibration of the engine body or insufficient tightening. In this case, the bolt may be easily sucked into the intake passage, damage the throttle valve on the downstream side, and may be sucked into the engine. The present invention is provided to address such an intake system problem.

[0007]

In order to solve the above problems, according to the present invention, in a surge tank of an internal combustion engine, an intake pipe is connected to an intake passage member extending from the engine body, and the intake passage is formed by connecting the intake pipe. In an intake device for an internal combustion engine that obtains an inertia supercharging effect during engine operation by extending the length, the intake pipe is formed of a resin material, and a collared bolt is press-fitted into a flange portion of the intake pipe to form the intake passage member. There is provided an intake device, characterized in that the flange portion of the intake pipe and the flange portion of the intake pipe are fastened via the collared bolt.

[0008]

[Function] Since the intake pipe is made of resin and the bolt with collar is press-fitted and integrated with it, if the bolt comes off, it will fall into the surge tank together with the intake pipe,
Suction into the engine intake system is prevented.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an intake device according to the present invention will be described below with reference to the drawings. Referring to FIG. 1 showing an external appearance perspective view of an intake device in which a part of a surge tank is cut out, and FIG. 2 showing a longitudinal section thereof, 1 is a cylinder head that serves as an engine body, 2 is an intake manifold connected to the cylinder head 1, 3 Is a throttle body as an intake passage member in the present invention.

In this embodiment, independent throttle valves 4 are provided inside the four throttle bodies 3 connected to the intake manifold 2 to form a so-called independent throttle engine.

Further, according to the present embodiment, the lower portion 5a of the surge tank 5 formed of a lightweight material such as an iron plate is abutted against the flange portion 3a of each throttle body 3, and the lower portion of the surge tank 5 is abutted. For 5a,
Four intake pipes 6 having bolts 7 are abutted against the flange portion 6a, and the lower portion 5a of the surge tank and the intake pipe 6 are integrally connected to the flange portion 3a of the throttle body 3 by the bolts 7. It

As is clear from the figure, the intake pipe 6 has a shape curved downward from its flange portion 6a so as to extend inside the cavity defined by the lower portion 5a of the surge tank. The detailed structure thereof will be described later.

The bolt 7 integrally attached to the intake pipe 6 is a so-called collared bolt for inserting the shaft portion 7a into the collar 8 as shown in the enlarged view of the mounted state in FIG. A screw (rolling screw) 7b having a thread diameter larger than the inner diameter of the collar 8 is formed at the tip of the shaft protruding from the collar 8 by, for example, a rolling process or the like. It does not fall out.

When the collared bolt 7 is attached to the intake pipe 6, the collar 8 is press-fitted into the hole 9 formed in the flange portion 6a of the intake pipe 6 so as to be integrated. The intake pipe 6 is attached to the throttle body 3 by forming a female screw 3b that engages with the screw 7b on the flange portion 3a of the throttle body 3 so that the intake pipe can be attached via the bolt 7. If the intake pipe 6 and the surge tank lower portion 5a are attached to the throttle body 3 as described above, next, as with the surge tank lower portion 5a, a surge with a gasket formed of a light material such as an iron plate is used. By fastening the tank cover 5b to the surge tank lower portion 3 with the bolt 10, one surge tank 5 is formed.

As described above, according to this embodiment, since the intake pipe 6 and the collared bolt 7 are integrated in advance prior to mounting on the throttle body 3, the bolt 7 may be temporarily suspended due to engine vibration or the like. Even if it may come off, the bolt alone does not fall off due to the above-mentioned reason, but it falls off together with the intake pipe 6 into the lower portion 5a of the surge tank, so that the bolt 7 is naturally sucked into the engine. There is no such thing.

Next, the structure of the resin intake pipe 6 will be described with reference to FIGS. According to the present embodiment, in the intake pipe 6, a component in which the flange portion 6a and the semi-cylindrical pipe lower portion 6b are integrated is butted against the semi-cylindrical pipe upper portion 6c, and these components are attached. It is an assembly that forms a cylinder by welding while vibrating, and the engagement of both parts is as shown in (A) of FIG. 6 which is an enlarged part A of FIG. A recess 11 is provided at the end of the component (the pipe lower side portion 6b in this embodiment), while a protrusion 12 of another component (the pipe upper portion 6c) is provided.
It is a form to engage.

Further, according to the present embodiment, the engaging portion near the bolt 7'may interfere with the tightening tool when tightening the bolt 7 ', which may make the tightening work difficult. The end portion of the component is limited to this portion and has a sectional shape as shown in FIG. 6B so that the engaging portion does not project outward from the pipe peripheral wall 6d. In the present embodiment, since the inner peripheral portion of the pipe is partially cut out, which is common to both the above-described engagement (butting) modes,
The welded resin portion does not protrude to the pipe inner wall surface 6e, and therefore the air carrying resistance is not increased by ensuring the smoothness of the pipe inner wall surface 6e.

[0018]

As described above, according to the present invention, in the intake device in which the intake pipe is fastened to the intake passage member inside the surge tank, the intake pipe and the collared bolt are integrated, so the bolt that has fallen off. Can be prevented from being sucked into the engine.
In addition, in the present invention, since the intake pipe is made of a resin material in order to enable the press-fitting of the collar, the weight of the entire intake device can be reduced as compared with the case where the intake pipe is formed by die casting or the like.

[Brief description of drawings]

FIG. 1 is an external perspective view of an intake device according to the present invention.

2 is a cross-sectional view of the device shown in FIG.

FIG. 3 is an enlarged view of the collared bolt shown in FIG.

FIG. 4 is an external perspective view of the intake pipe according to the present embodiment.

5 is a sectional view of the intake pipe taken along line VV of FIG.

6 shows a component engaging portion of the intake pipe of FIG.
5A is an enlarged sectional view of a portion A of FIG. 5 and FIG.

[Explanation of symbols]

 1 ... Cylinder head (engine body) 3 ... Throttle body (intake passage member) 3a ... Throttle body flange 5 ... Surge tank 6 ... Intake pipe 6a ... Intake pipe flange 7,7 '... Colored bolt 8 ... Color

Front page continued (72) Inventor Mikio Nakajima 1 Toyota-cho, Toyota-shi, Aichi Toyota Motor Co., Ltd. (72) Inventor Hidetoshi Ishihara 1 Nagachihata, Ochiai, Kasuga-cho, Nishikasugai-gun, Aichi Toyoda Gosei Co., Ltd. ( 72) Inventor Joji Kasugai 1 Nagachihata, Ochiai, Kasuga-cho, Nishi-Kasugai-gun, Aichi Toyoda Gosei Co., Ltd.

Claims (1)

[Claims] 1. Inside a surge tank of an internal combustion engine,
In an intake device for an internal combustion engine, wherein an intake pipe is connected to an intake passage member extending from an engine body, and an intake supercharging effect during engine operation is obtained by extending the intake passage length by the intake pipe connection, the intake pipe is made of a resin material. As it forms
An intake device characterized in that a collared bolt is press-fitted into a flange portion of the intake pipe, and the flange portion of the intake passage member and the flange portion of the intake pipe are fastened via the collared bolt.