JPH08200104A - Air quantity controller for internal combustion engine - Google Patents

Abstract

PURPOSE: To prevent abnormal sound to be generated caused by contact of a throttle valve with a bore part and abrasion of both by eliminating the abrasion in the clearance between back springs caused by vibration. CONSTITUTION: Back springs 15A, 16A are constituted of compression torsion springs and energize a throttle shaft 4 leftward as shown in the figure. The thrust load of a thrust spring 18 is increased or decreased by adjusting a screw 20, so as to hold a throttle valve 3 in the neutral position not to be brought in contact with a bore part 1A. Vibration of the back springs is decreased, and the inter-wire abrasion is prevented. Abrasion of the throttle valve to the bore part is decreased, and the change of air quantities is eliminated. Accordingly, the idle rotational number of an engine is stabilized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air quantity control device for an internal combustion engine.

[0002]

2. Description of the Related Art As this type of device, an air amount control device shown in FIGS.
54 publication).

In FIGS. 7 and 8, 1 is a main body of the body, 2 is a body
Is an air passage provided in the body 1 and 3 is a throttle valve, which is fixed to the throttle shaft 4 with a screw 5. Reference numerals 6 and 6 denote bearings provided on the body 1 for rotatably supporting the throttle shaft 4. Reference numerals 7 and 7 are dust seals made of an elastic body, 8 is a throttle lever fixed to one end of the throttle shaft 4 with a spring washer 9 and a nut 10, and 11 is a sensor lever fixed to the other end of the throttle shaft 4 with a nut 12.

Reference numeral 13 is a first spring guide fitted to one end of the throttle shaft 4, 14 is a second spring guide fitted to the body 1, and 15 and 16 are first and second back springs. Guides 13 and 14
It is mounted between the throttle lever 8 and the main body of the vehicle via the, and always urges the throttle lever 8 in the direction of closing the throttle valve 3. Reference numeral 17 is a throttle position sensor that is linked to the throttle shaft 4 via the sensor lever 11.

Both back springs 15 and 16 are coil springs and are locked between the body 1 and the throttle lever 8 so that thrust load in the axial direction of the throttle shaft 4 is not generated.

[0006]

SUMMARY OF THE INVENTION In the above conventional technique,
When an external force such as vibration is applied, the back springs 15 and 16
Shakes to cause line wear, and the throttle shaft 4
Moves in the axial direction, the throttle valve 3 contacts and slides with the bore portion 1A of FIG. 8, and both wear. That is, the gap indicated by L in FIG. 8 disappears due to vibration, slides and collides, and wears each other.

Further, a hit sound (abnormal sound) between the throttle valve and the bore portion is generated. Then, there is a problem that the idle rotation of the engine becomes unstable due to a decrease in throttle valve closing force due to wear of the wires between springs and a change in the air amount due to wear of the throttle valve and the bore portion.

Therefore, an object of the present invention is to provide an air amount control device for an internal combustion engine which can eliminate such abnormal noise and problems.

[0009]

In order to achieve the above object, the invention of claim 1 energizes the throttle valve (3) in the closing direction and applies a unidirectional thrust load to the throttle shaft (4). Back spring (15
A) (16A) and thrust spring (18) that applies thrust load in the other direction to the throttle shaft (4)
And a screw (20) for adjusting the thrust load of the thrust spring (18).

In this invention, since the back spring has its own thrust load, it is less likely to shake even if it receives external vibration. Also, by adjusting the screw so that the throttle valve is in the neutral position, the throttle valve and the bore are not hit or worn.

According to a second aspect of the present invention, the back springs (15A) (16A) for urging the throttle valve (3) in the closing direction and applying a thrust load in one direction to the throttle shaft (4), and the throttle shaft (4). ) And body (1) with throttle shaft (4)
It is characterized by comprising an O-ring (23) and a bush (22) for restricting the axial movement of the and holding the neutral position.

In the present invention, the back spring is less likely to vibrate due to vibration, as in the first invention. Further, the axial movement of the throttle shaft is restricted, so that the throttle valve and the bore are prevented from hitting or wearing.

According to the third aspect of the present invention, the throttle shaft (4) and the back springs (15A) (16A) for urging the throttle valve (3) in the closing direction and applying a thrust load in one direction to the throttle shaft (4). ) And body (1) with throttle shaft (4)
It is characterized by including an annular protrusion (24) and a bush (22) for restricting the axial movement of the and holding it in a neutral position.

In the present invention, as in the second invention, the runout of the back spring and the contact and wear of the throttle valve and the bore are eliminated.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a first embodiment of the present invention. Since the same structural parts as those of the prior art described in FIGS. 7 and 8 are given the same reference numerals, the description thereof will be omitted and different parts will be described. Mainly explained.

The first back spring 15A and the second back spring 16A are composed of compression torsion springs, which urge the throttle valve 3 in the closing direction and apply a thrust load to the left direction in the drawing to the throttle shaft 4. Throttle lever 8 and body 1
It is locked to.

The thrust spring 18 is also a compression coil spring and urges the throttle shaft 4 to the right in the figure via the sensor lever 11. The left end of the thrust spring 18 is attached to the screw 20 via a spring guide 19.
It is adjusted in the left-right direction by the lower end taper portion. Reference numeral 21 is an O-ring fitted between the head of the screw 20 and the body body 1. By adjusting the screw 20 screwed to the body body 1 to adjust the thrust load of the thrust spring 18, the throttle valve 3 is held in the neutral position, and the contact and wear between the throttle valve 3 and the bore portion 1A are eliminated.
That is, the screw 20 is adjusted so that the clearance between the screw 20 and the bore when the throttle valve is fully opened is equalized to the left and right.

2 and 3 show a second embodiment of the present invention, in which the body 22 is provided with bushes 22 and 22 having an annular V-shaped groove for restricting the leftward movement of the throttle shaft 4.
O-rings 23, 23 fitted in the V-shaped grooves of the bushes 22, 22 are fitted in the outer peripheral groove of the throttle shaft 4.

The structure of the other parts is almost similar to that of the first embodiment shown in FIG. In the second embodiment, the throttle shaft 4
Receives the thrust load of both back springs 15A and 16A toward the left in the drawing, but the bushes 22, 22 and O
The position in the thrust direction is regulated by the rings 23, 23, and the throttle valve 3 is supported at the neutral position.

FIG. 4 shows a third embodiment of the present invention, which is shown in FIGS.
Compared to the second embodiment, the bush 22 and the O-ring 23
The difference is that there is only one set, but the effects are the same.

FIG. 5 and FIG. 6 show a fourth embodiment of the present invention.
In comparison with the third embodiment of the present invention, an annular projection 24 formed on the outer circumference of the throttle shaft 4 is provided instead of the O-ring 23, and the annular projection 24 is fitted into the V-shaped groove of the bush 22 to thereby obtain the throttle shaft. The throttle valve 3 is held in the neutral position by restricting the axial movement of the throttle valve 4.

[0022]

Since the air amount control device for an internal combustion engine of the present invention is constructed as described above, the vibration of the back spring due to the vibration from the outside is reduced and the line wear does not occur. Therefore, the throttle valve closing force is stable for a long period of time, and the idle speed of the engine is stable.

[Brief description of drawings]

FIG. 1 is a sectional view of a first embodiment of the present invention in a fully closed state.

FIG. 2 is a fully closed sectional view of a second embodiment of the present invention.

FIG. 3 is an enlarged view of part A of FIG.

FIG. 4 is a sectional view of a third embodiment of the present invention in a fully closed state.

FIG. 5 is a sectional view of a fully closed state of a fourth embodiment of the present invention.

FIG. 6 is an enlarged view of part B in FIG.

FIG. 7 is a sectional view of a conventional technique in a fully closed state.

FIG. 8 is a sectional view of a conventional technique in a fully opened state.

[Explanation of symbols]

 1 Body 3 Throttle valve 4 Throttle shaft 15A, 16A Back spring 18 Thrust spring 20 Screw 22 Bush 23 O-ring 24 Annular protrusion

Claims (3)

[Claims] 1. A back spring for energizing a throttle valve in a closing direction and applying a thrust load in one direction to a throttle shaft, a thrust spring for applying a thrust load in another direction to a throttle shaft, and a thrust load of the thrust spring are adjusted. An air amount control device for an internal combustion engine, comprising: 2. A back spring for energizing the throttle valve in the closing direction and applying a thrust load in one direction to the throttle shaft, and the throttle shaft and the body body are regulated in the axial direction and held in a neutral position. An air quantity control device for an internal combustion engine, comprising: an O-ring and a bush. 3. A back spring for energizing the throttle valve in the closing direction and applying a thrust load in one direction to the throttle shaft, and the throttle shaft and the body body are restrained from axial movement of the throttle shaft and held in a neutral position. An air flow control device for an internal combustion engine, comprising an annular protrusion and a bush.