JP3197729B2 - Throttle valve opening and closing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a throttle valve opening / closing device for opening / closing a throttle valve mounted on a throttle body or a carburetor of an internal combustion engine.

[0002]

2. Description of the Related Art A throttle valve opening / closing device of this type is known from Japanese Utility Model Publication No. 1-26911.

In this type, as shown in FIG. 6, a throttle valve 2 for opening and closing an intake passage of a throttle body 1 is fixed to a throttle shaft 4 with screws 3, and the throttle shaft 4 is rotatable about the throttle body 1. It is supported by

The right end of the throttle shaft 4 protrudes from the throttle body 1, and a throttle arm 5 and a throttle lever 6 are fastened to the protrusion by a nut 8 via a spring washer 7.

Reference numeral 9 denotes a spring guide rotatably engaged with the throttle shaft 4, and reference numeral 10 denotes a back spring loosely wound around the spring guide 9, and biases the throttle shaft 4 in a direction to close the throttle valve 2. The tip hook portion 10a of the back spring 10 is engaged with a boss-shaped stopper 1a protruding from the throttle body 1. Also, the other end hook portion 10b of the back spring 10
Is engaged with the throttle arm 5.

Reference numeral 9a denotes a guide portion for preventing one end of the back spring 10 from coming off, and reference numeral 11 denotes a guide plate for preventing the other end from coming off. The stopper 1a is formed of an aluminum alloy integrally with the throttle body 1, the back spring 10 is formed of spring steel, and the hook 10a at the tip of the back spring 10 is pressed against one surface of the stopper 1a by the elasticity of the spring itself.

[0007]

In the above prior art,
The tip hook portion 10a of the back spring 10 collides and slides relatively with the stopper 1a due to engine vibration, and the stopper 1a, which has particularly low wear resistance, wears, and the load (characteristics) of the back spring 10 changes. There was a problem.

When the back spring 10 is assembled, the gloves (work gloves) of the worker are caught on the tip of the tip hook 10a of the back spring 10 and the hook 10a
May come off from the stopper 1a, which is also a problem.

Accordingly, an object of the present invention is to provide a throttle valve opening / closing device which can solve these problems.

[0010]

In order to achieve the above object, a throttle valve opening / closing device according to the present invention comprises a spring guide fitted to a throttle shaft (4), wherein a throttle valve (2) is attached in a valve closing direction. A back spring that is energized is wound and a tip hook of the back spring is locked by a stopper (1a).
A cylindrical cover (9a) surrounding the periphery of (a) is formed integrally with the spring guide (9A), and the cover (9a) is made of heat-resistant and wear-resistant resin. (9b) is set at a position extending beyond the tip of the hook portion (10a, 10'a) at the tip of the back spring (10, 10 '), and the back spring (10, 10') is set.
Hooks (10a, 10'a) at the tip of
The hook (10a, 10 ') is inserted into the bar (9a).
a) is surrounded by the cover (9a) and the hook portion
The tip of (10a, 10'a) fits inside the cover (9a).
Cover (10a, 10'a)
held in a), the characterized in that engaged the cover portion (9a) before Symbol stopper (1a).

According to a second aspect of the present invention, there is provided the throttle valve opening and closing device according to the first aspect, wherein the spring guide (9)
A cover (9c) for closing the tip of the cover (9a) of (A) is provided.

[0012]

The cover (9a) of the spring guide (9A) enters between the hook (10a, 10'a) of the back spring (10, 10 ') and the stopper (1a). Does not collide or slide directly.

According to the second aspect of the present invention, the cover (9)
The cover (9c) in (a) prevents foreign matter from entering the cover (9a), and prevents abnormal wear of the tip hooks (10a, 10'a) and the cover (9a).

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the embodiment, the same reference numerals as those in the prior art of FIG.
Since they perform the same function, their description is omitted.

FIGS. 1 to 4 show a first embodiment of the present invention. The back spring for urging the throttle valve 2 in the closing direction is such that even if one of the back springs is cut off, the remaining one will open the throttle valve 2. 10 and 10 'so that they can be closed
Are provided.

Reference numeral 5A denotes a throttle arm which is fastened to the throttle shaft 4 with a nut 8 together with the throttle lever 6. 9A and 9B are spring guides. One spring guide 9A rotatably fits with a boss 1b formed coaxially with the throttle shaft 4 on the throttle body 1, and the other spring guide 9B rotates on the throttle shaft 4. Mating is possible.

The two back springs 10, 10 'are wound around spring guides 9A and 9B as shown in the figure, and hook portions 10a and 10'a at their respective ends are formed integrally with the spring guide 9A. It is inserted in the cover part 9a of the shape.

The cover portion 9a is formed to extend substantially in the radial direction of the spring guide 9A, withstands high temperatures in the engine room of the automobile, and has the back springs 10, 10 '.
Also, a wear-resistant polyamide-based resin or phenol-based resin that is hard to be worn by relative movement with the stopper 1a is used.

The distal end (outer peripheral end) 9b of the cover 9a is set at a position extended from the distal ends of the hooks 10a and 10'a of the back springs 10 and 10 'in the assembled state. In other words, in the assembled state, the hook parts 10a, 1
The tip of 0'a is retracted from the tip 9b of the cover 9a (see FIG. 3).

The other end hook portions 10b, 10'b of the back springs 10, 10 'are connected to the throttle arm 5A as shown in FIG.
It is hooked like. In the first embodiment, the heat resistance
The abrasion-resistant cover portion 9a includes the back springs 10, 1
Since the hook portions 10a and 10'a surround the 0 'tip hook portions 10a and 10'a and do not directly contact the stopper 1a of the throttle body 1, wear due to vibration is eliminated.

Further, the hook portions 10a and 10'a are not caught by the worker's glove during assembly, and do not come off the stopper 1a.

FIG. 5 shows a second embodiment of the present invention, in which a lid 9c for closing a tip of a cover 9a of a spring guide 9A is integrally formed. By doing so, the first embodiment,
Foreign matter is prevented from entering through the upper opening of the cover 9a. Therefore, there is no possibility that the hook portions 10a and 10'a of the back springs 10 and 10 'and the cover portion 9a are abnormally worn by the invading foreign matter.

[0023]

Since the throttle valve opening / closing device of the present invention is constructed as described above, the hook portions (10a, 10'a) of the back spring come off due to vibration or come off by the worker's gloves. No more.

Further, since the hook portions (10a, 10'a) and the stoppers of the throttle body do not directly contact each other, wear due to vibration is reduced, and the spring load characteristics are not changed and reliability is improved.

Furthermore, according to the second aspect of the present invention, foreign substances can be prevented from entering the cover, and abnormal wear due to the foreign substances can be prevented.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a first embodiment of the present invention.

2A is a side view of a part of the embodiment of FIG. 1, and FIG. 2B is a view of a part of FIG.

FIG. 3A is an enlarged view of a part of FIG. 2A;
FIG. 2B is a partial view of FIG.

FIGS. 4A and 4B are views of a spring guide used in the first embodiment of the present invention, wherein FIG. 4A is a front view in vertical section, FIG.
(C) is a plan view, (d) is a rear view, and (e) is a left side view.

FIG. 5 is an enlarged side view of a main part of a second embodiment of the present invention.

FIG. 6 is a partial longitudinal front view of a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Throttle body 1a Stopper 2 Throttle valve 4 Throttle shaft 9A Spring guide 9a Cover part 9b Tip 9c Lid 10, 10 'Back spring 10a, 10'a Hook part

Claims (2)

(57) [Claims] 1. A back spring for biasing a throttle valve (2) in a valve closing direction is wound around a spring guide fitted to a throttle shaft (4), and a front hook portion of the back spring is connected to a stopper (1a). The hooks (1) of the back springs (10, 10 ')
0a, 10'a), a cylindrical cover part (9a) surrounding the periphery
Is formed integrally with the spring guide (9A), the cover (9a) is made of heat-resistant and wear-resistant resin, and the tip (9b) of the cover is attached to the back spring (10, 10).
The hook at the tip of the back spring (10, 10 ') is set at a position extended from the tip of the hook (10a, 10'a) at the tip of the back spring (10').
Parts (10a, 10'a) in the cylindrical cover (9a)
And hooks (10a, 10'a)
Surrounded by a bar (9a) and having hook portions (10a, 10 ').
hook with the tip of a) set in the cover (9a)
Parts (10a, 10'a) and held by the cover (9a) and the throttle valve opening and closing device being characterized in that engaging the cover portion (9a) before Symbol stopper (1a). 2. The throttle valve opening / closing device according to claim 1, further comprising a lid (9c) for closing a tip of a cover (9a) of the spring guide (9A).