JPH11324735A - Air flow controller for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent lowering of retention force of an intake pipe wall to a bearing, to prevent deformation of the intake pipe wall, and to improve assembling workability of the bearing to the intake pipe. SOLUTION: An air flow controller for an internal combustion engine comprises an intake pipe 10 made of a synthetic resin, a throttle valve shaft 11 penetrating both through holes 10b formed in a wall 10a of the intake pipe 10 orthogonal to an axial direction of the intake pipe 10, a throttle valve 3 which is fixed to the throttle valve shaft 11 and adjusts an air flow rate in the intake pipe 10 by rotation of the throttle valve shaft 11, ball bearings 4 which are provided in the through holes 10b and rotatably bear the throttle valve shaft 11, and elastic bodies 12 which are provided outside the ball bearings 4 in the through holes 10b and press the ball bearings 4 in a radial inside direction of the intake pipe 10. Each the elastic body 12 is locked in a groove part 11a annularly formed around an outer circumference of the throttle valve shaft 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air flow control device for an internal combustion engine having a throttle valve for adjusting the amount of air flowing through an intake pipe by rotating a throttle valve shaft rotatably supported by a bearing. .

[0002]

2. Description of the Related Art FIG. 3 is a sectional view of a conventional air flow control device for an internal combustion engine described in Japanese Utility Model Publication No. Sho 60-26201.
At right angles to the axial direction of the intake pipe 1.
Throttle shaft 2 penetrating through hole 1b formed in wall 1a
A throttle valve 3 fixed to the throttle valve shaft 2 to adjust the amount of air flowing through the intake pipe 1 by rotation of the throttle valve shaft 2;
And a ball bearing 4 which rotatably supports the throttle valve shaft 2. The ball bearing 4 includes an inner ring 4a fixed to the throttle valve shaft 2, a ball 4b, and an outer ring 4c fixed to the through hole 1b. Ball bearing 4
Is press-fitted and fixed in the through hole 1b, and movement of the throttle valve shaft 2 in the axial direction and the radial direction is prevented.

In this air flow control device for an internal combustion engine, the degree of opening of the throttle valve 3 in the intake pipe 1 is changed by rotation of a throttle valve shaft 2 rotatably supported by a ball bearing 4. The amount of air flowing through is adjusted.

FIG. 4 is a sectional view showing another example of a conventional air flow control device for an internal combustion engine. In this example, a through hole 1b is shown.
The ball bearing 4 is pressed in a radially inward direction of the intake pipe 1 by a metal pressing member 5 pressed into the through hole 1b.
3 is prevented from moving in the axial direction of the throttle valve shaft 2 from the conventional example of FIG.

[0005]

In the conventional air flow control device for an internal combustion engine shown in FIG. 3, the ball bearing 4 is pressed into the through hole 1b, and in the example of FIG. 4, the pressing member 5 is inserted into the through hole 1b. The ball bearing 4 is fixed to the wall portion 1a of the metal intake pipe 1 by press-fitting. However, when the ball bearing 4 and the pressing member 5 are press-fitted into the through-holes of the intake pipe made of a synthetic resin that can be easily formed and reduced in weight instead of the metal intake pipe 1, Such a problem was remarkable. I. Due to the creep phenomenon of the synthetic resin, the holding force with respect to the ball bearing 4 decreases over time, and the throttle valve shaft 2
Does not rotate smoothly. B. When the ball bearing 4 and the pressing member 5 are press-fitted, the load tends to deform the wall of the intake pipe. C. For assembling work of the ball bearing 4 to the intake pipe,
The troublesome press-fitting work of the ball bearing 4 and the pressing member 5 is required, and the efficiency of the assembling work is low.
The press-fit load of the ball bearing 4 must be strictly controlled.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, and it is possible to prevent a reduction in holding force of a wall of an intake pipe against a bearing and a deformation of a wall of an intake pipe. It is another object of the present invention to provide an air flow control device for an internal combustion engine having improved workability of assembling a bearing with respect to an intake pipe.

[0007]

According to a first aspect of the present invention, there is provided an air flow control device for an internal combustion engine, comprising: an intake pipe made of synthetic resin; and a wall of the intake pipe orthogonal to an axial direction of the intake pipe. A throttle valve shaft that penetrates a through hole formed in the portion, a throttle valve fixed to the throttle valve shaft to adjust the amount of air flowing through the intake pipe by rotation of the throttle valve shaft, and the throttle valve provided in the through hole. A bearing rotatably supported by a shaft; and an elastic body provided outside the bearing in the through hole and pressing the bearing in a radially inward direction of the intake pipe. It is locked in a groove formed to extend in the direction.

In the air flow control device for an internal combustion engine according to the second aspect, the elastic body is made of a rubber material.

In the air flow control device for an internal combustion engine according to the third aspect, the elastic body is formed of a disc spring.

In the air flow control device for an internal combustion engine according to a fourth aspect, the bearing is a ball bearing.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 The air flow control device for an internal combustion engine includes an intake pipe 10 made of a polyamide resin containing glass fibers, and a through-hole formed in a wall 10 a of the intake pipe 10 orthogonal to the axial direction of the intake pipe 10. A throttle valve 11 penetrating through the hole 10b, a throttle valve 3 fixed to the throttle valve shaft 11 to adjust the amount of air flowing through the intake pipe 10 by rotation of the throttle valve shaft 11, and a throttle valve provided in the through hole 10b. A ball bearing 4 which is a bearing rotatably supporting the shaft 11; and a ring-shaped rubber material provided outside the ball bearing 4 in the through hole 10b and pressing the ball bearing 4 radially inward of the intake pipe 10. Elastic body 1
2 is provided. The ball bearing 4 has a throttle valve shaft 11
And an outer ring 4c abutting on the through hole 10b. Grooves 11 a are formed at both ends of the throttle valve shaft 11 so as to extend in the circumferential direction of the throttle valve shaft 11. The elastic body 12 is locked in the groove 11a. The elastic body 12 is in contact with the inner ring 4 a of the ball bearing 4 and presses the inner ring 4 a in a radially inner direction of the intake pipe 10.

In this air flow control device for an internal combustion engine, the ball bearing 4 is inserted until it comes into contact with the bottom 10c of the through hole 10b, and then the elastic body 12 is mounted in the groove 11a. As a result, the ball bearing 4 is sandwiched between the bottom 10c of the through hole 10b and the elastic body 12 and is urged in a radially inward direction of the intake pipe 10 by the elastic body 12 contacting the inner ring 4a of the ball bearing 4. Through hole 10b in the state
Is positioned within. Conventionally, ball bearing 4
Is press-fitted into the through hole 1b, however, in this embodiment, such troublesome press-fitting work is not usually required. The ball bearing 4 is provided between the elastic body 12 and the bottom 10c of the through hole 10b within the through hole 10b.
Since it is sandwiched while being urged radially inward of the intake pipe 10 by the elastic force of 2, the deformation of the wall 10a due to the press-fitting of the ball bearing 4 can be prevented. Further, even if the ball bearing 4 is press-fitted into the through hole 10b and a creep phenomenon occurs, so-called "looseness" occurs in the ball bearing 4, the looseness is caused by the elastic body 12 abutting on the inner ring 4a of the ball bearing 4. Of the ball bearing 4 by the intake pipe 1 can be prevented from lowering. Further, since the elastic body 12 is locked in the groove 11a, the elastic body 12 is positioned at that position, and the ball bearing 4 can be surely urged radially inward of the intake pipe 10.

Embodiment 2 FIG. Second Embodiment FIG. 2 is a sectional view of an air flow control device for an internal combustion engine according to a second embodiment of the present invention, in which an elastic body 13 made of a metal disc spring is used in place of the ring-shaped rubber elastic body 12. It is the same as Embodiment 1 except for the differences.

Although the ball bearing 4 is used as the bearing, the present invention is not limited to this. The elastic body may be other than rubber and disc springs.

[0015]

As described above, according to the air flow control device for an internal combustion engine according to the first aspect of the present invention, the intake pipe made of synthetic resin is perpendicular to the axial direction of the intake pipe. A throttle valve shaft that penetrates a through hole formed in a wall portion of the intake pipe, a throttle valve fixed to the throttle valve shaft to adjust the amount of air flowing through the intake pipe by rotation of the throttle valve shaft, and provided in the through hole. A bearing rotatably supporting the throttle valve shaft, and an elastic member provided outside the bearing in the through hole and pressing the bearing radially inward of the intake pipe. Locked to the groove formed extending in the circumferential direction of the valve shaft, it is possible to prevent the holding force of the wall of the intake pipe against the bearing from decreasing and to prevent the wall of the intake pipe from being deformed. The assembling workability is improved.

According to the air flow control device for an internal combustion engine according to the second aspect, since the elastic body is made of a rubber material, the bearing is sucked into the through-hole with a low cost and a simple structure. It can be pressed radially inward of the tube.

According to the air flow control device for an internal combustion engine according to the third aspect of the present invention, since the elastic body is formed of a disc spring, the bearing is sucked in the through hole with a low cost and a simple structure. It can be pressed radially inward of the tube.

According to the air flow control device for an internal combustion engine according to the fourth aspect, since the bearing is a ball bearing, the throttle valve shaft can be rotatably supported with a low cost and a simple configuration. it can.

[Brief description of the drawings]

FIG. 1 is a sectional view of an air flow control device for an internal combustion engine according to Embodiment 1 of the present invention.

FIG. 2 is a sectional view of an air flow control device for an internal combustion engine according to Embodiment 2 of the present invention.

FIG. 3 is a sectional view of a conventional air flow control device for an internal combustion engine.

FIG. 4 is a cross-sectional view showing another example of a conventional air flow control device for an internal combustion engine.

[Explanation of symbols]

3 Throttle valve, 4 ball bearing (bearing), 4a inner ring, 10 intake pipe, 10a wall, 10b through hole, 1
1 Throttle valve shaft, 11a groove, 12, 13 elastic body.

Claims (4)

[Claims] An intake pipe made of a synthetic resin, a throttle valve shaft penetrating through a through hole formed in a wall portion of the intake pipe at right angles to an axial direction of the intake pipe, and fixed to the throttle valve shaft. A throttle valve that adjusts the amount of air flowing through the intake pipe by rotating the throttle valve shaft;
A bearing provided in the through hole and rotatably supporting the throttle valve shaft, and an elastic body provided outside the bearing in the through hole and pressing the bearing in a radially inward direction of the intake pipe, This elastic body is an air flow control device for an internal combustion engine that is locked in a groove formed to extend in the circumferential direction of the throttle valve shaft. 2. An elastic body made of a rubber material.
An air flow control device for an internal combustion engine according to claim 1. 3. The air flow control device for an internal combustion engine according to claim 1, wherein the elastic body is constituted by a disc spring. 4. The air flow control device for an internal combustion engine according to claim 1, wherein the bearing is a ball bearing.