JP3357965B2 - Valve rotator for internal combustion engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve rotator for forcibly rotating an engine valve around its axis.

[0002]

2. Description of the Related Art As a valve rotator of this type, a steel ball or roller type and a coil spring type are known . FIG. 3 shows a conventional coil spring type valve rotator.

A pair of cotters (03) facing in a radial direction are engaged with an annular groove (02) formed at the shaft end of the engine valve (01). A substantially cylindrical rotator body (04) having an outward flange (04a) connected to the upper end of the body is fitted to the outer peripheral surface to be formed.

[0004] On the lower surface of the outward flange (04a), an upward concave groove (05) is formed over the entire circumference in the circumferential direction, and the lower end of the concave groove (05) is lower than the concave groove (05). A slightly protruding rotational force applying member, that is, a coil spring (06) is housed therein.

A stepped ring-shaped retainer (07) having a small diameter in the lower half is externally fitted to the rotator body (04), and a valve spring is mounted on the lower surface of the large-diameter portion above the retainer (07). The upper end of (08) is in contact.

An outer peripheral portion of the rotator body (04) and a retainer
The inner and outer edges of the disc spring (09) are respectively engaged with the inner periphery of the large diameter portion of (07), and the coil spring (06) is pressed upward by the upper surface of the disc spring (09). are doing.

When pressed by a rocker arm (not shown), the engine valve (01) starts to open, its shaft (01a) descends, and when the load of the valve spring (08) increases, the disc spring (09)
Is bent upward by the retainer (07). Therefore, the coil spring (06) in contact with the inner surface in the concave groove (05)
Is strongly pressed and falls down in a certain circumferential direction, whereby the rotator body (04) is horizontally rotated in the direction of the arrow as shown in FIG. 4 by the horizontal force, and the engine valve (01) is , And is forcibly rotated about an axis via a cotter (03).

[0008]

The most obstacle in increasing the permissible engine speed is the mass of the valve train. The larger the mass of the valve train, the larger the inertial mass and the larger the valve body when the valve is closed. Dance and reduce engine performance.

In view of such a viewpoint, the valve rotator as described above is disadvantageous in mass because the number of parts is large and each part is relatively large, and the manufacturing cost is high. There's a problem. Therefore, further weight reduction and cost reduction of the valve rotator are required.

In the conventional valve rotator, the coil spring (06) and the disc spring (09) are covered in a bag shape by the rotator body (04) and the retainer (07). Droplets hardly spread to the contact portions between the members, and it was difficult to obtain good lubricity.

Further, in the conventional valve rotator, the upper end (07a) of the retainer (07) is engaged with the rotator body (04) by inwardly caulking, so that there is a variation in the caulking method. When the rotator body (04) comes into strong contact with the rotator body (04), the rotation of the rotator body (04) becomes uneven,
The original function of the valve rotator may be impaired.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems. By eliminating the retainer, the weight and cost can be reduced, the lubricity can be improved, and the engine valve can be forcibly rotated. Made it possible to
An object of the present invention is to provide a valve rotator for an internal combustion engine.

[0013]

According to the present invention, the above-mentioned problem is solved as follows. (1) On the lower surface of the outward flange of the rotator body fixed to the shaft end of the engine valve pointing in the up-down direction, a plurality of or upwardly extending annular concave grooves arranged on the same circumference are formed. The lower surface of the rotating force applying member housed in the groove so as to be movable or tiltable is brought into contact with the upper surface of the disc spring, and the lower part of the lower surface of the disc spring is pressed against the upper end of the valve spring. > And, at the outer peripheral end of the outward flange, form a downward cylindrical portion
Then, the upper end of the valve spring is housed in the cylindrical portion .

(2) On the upper surface of the outward flange of the rotator body, which is provided so as not to rotate around the axis, in the through-hole of the shaft portion of the engine valve in the cylinder head, a plurality of annular recesses arranged in the circumferential direction or the entire annular recess are provided. A groove is formed, and the upper surface of the rotational force applying member housed in the groove so as to be movable or tiltable is brought into contact with the lower surface of the disc spring , and
The upper part of the face, upper end is pressed against the lower end of the supported valve spring by the spring bearing integral with the engine valve, before
Provide an upwardly facing body and a guide tube inside and outside of the outward facing collar
At the same time, at the upper end of the body, the disc spring is prevented from falling off.
An outward bent portion is provided, inside the guide tube, below the valve spring.
Position the end.

(3) In the above item (2) , the rotator body is formed by pressing a thin steel plate.

[0016]

According to the first aspect of the present invention, when the load of the valve spring increases due to the opening of the engine valve, the disc spring directly in contact with the valve spring flexes upward, and the rotating spring accommodated in the groove of the rotator body. When the force applying member moves or tilts, the engine valve is rotated horizontally together with the rotator body.

According to the second and third aspects of the present invention, when the load on the valve spring increases when the engine valve starts to open,
The disc spring directly in contact with the valve spring bends downward, and the rotational force imparting member accommodated in the concave groove of the rotator body moves or tilts, so that the engine valve is moved through the disc spring, the valve spring and the spring receiver. And rotate horizontally.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. In addition, the same members as those of the conventional example shown in FIG.
A detailed description thereof will be omitted.

FIG. 1 shows a first embodiment of the present invention, in which a short cylindrical portion (10b) is provided at the outer peripheral end of an outward flange (10a) of a rotator body (10) having substantially the same shape as the conventional one. However, they are connected downward.

The disc spring (9), whose outer peripheral portion is inclined downward, is connected to the cylindrical portion (10).
The snap ring (11) housed in the b) and fixed to the outer peripheral surface of the body (10c) of the rotator body (10) prevents the rotator from falling off. The upper end of the valve spring (8) is in contact with the lower surface near the outer periphery of the disc spring (9), and is prevented from moving laterally in the cylindrical portion (10b).

When the engine valve (1) starts to open, the valve spring
When the load of (8) increases and the disc spring (9) flexes upward, the coil spring (6), which is a rotational force applying member, is strongly pressed by the disc spring (9) and falls down to one side. The rotator body (10) is horizontally rotated by the horizontal force at this time, as in the conventional case, and the engine valve (1) is forcibly rotated.

In the valve rotator of the above-described embodiment, since the upper end of the valve spring (8) is brought into direct contact with the disc spring (9) to eliminate the conventional retainer, the cost is reduced and the dynamics is reduced. Since the weight of the valve system can be reduced, the inertial mass can be reduced and the allowable rotation speed of the engine can be increased.

The lower surface of the outward flange (10a) of the rotator body (10) in which the coil spring (6) and the disc spring (9) are housed is largely open, so that the lubrication scattered by the valve operating movement is reduced. The oil easily enters the recessed portion such as the coil spring (6), and the lubrication of each member is improved, so that the abrasion of the contact portion can be suppressed.

Further, by eliminating the retainer,
The caulking method can prevent the rotation failure of the rotator body, which has conventionally occurred, and also improves the assemblability of the valve rotator.

FIG. 2 shows a second embodiment of the present invention. This embodiment shows a lower mold in which a valve rotator is attached to the lower end of a valve spring (8). The rotator body (17) is formed by pressing a relatively thin steel plate to form a body (17).
At the lower end of a), an outward recess (outward flange) (17b) for accommodating the coil spring (6) is provided continuously.
A disc spring (16), which is inclined upward and away from the center, is brought into contact with the upper surface of the coil spring (6) housed in the housing recess (17b). An outward bent portion (17c) for preventing the disc spring (16) from falling off is continuously provided at the upper end of the body (17a).

The body (17a) at the center of the rotator body (17)
Is fitted non-rotatably into a valve guide (14) through which the shaft (1a) of the engine valve (1) is inserted, and a spring receiver (15) is stopped at the shaft end of the engine valve (1). Is being worn.

The accommodation recess (17) in the rotator body (17)
An upwardly directed guide cylinder (17d) having an L-shaped cross section is continuously provided at the outer peripheral end of b).

The lower end of the valve spring (8) is in contact with the upper part of the disc spring (16) inclined upward, that is, the upper surface near the outer peripheral end, and the upper end is in contact with the lower surface of the spring receiver (15). ing. The lower end of the valve spring (8) is located in the guide cylinder (17d), and is restricted from moving laterally. Therefore, the second
In the embodiment, a concave hole (not shown) is formed in the cylinder head (13).
Need not be formed so that the inner wall restricts the lateral movement of the valve spring (8).

When the rotator main body (17) is formed by pressing, as in the valve rotator of the second embodiment, the manufacturing process is simplified as compared with the case of cold forging or sintering. Snap ring to prevent the disc spring (16) from falling off
(Not shown) can be eliminated, so that the number of parts can be reduced and cost can be reduced.

In each of the above embodiments, the coil spring (6) is used as the rotational force applying member, but a steel ball or a roller may be used instead. In this case, as in a general valve rotator, a steel ball or roller is always grooved.
(5) It is preferable to use a compression coil spring which urges downwardly on the inclined surface inside.

[0031]

According to the present invention, the following effects can be obtained. (a) The valve spring is directly in contact with the disc spring, and the conventional retainer is eliminated, so that the valve train can be reduced in weight.
The allowable rotation speed of the engine can be increased (claims 1 and 2).

(B) As a result of the elimination of the retainer, the engine valve can be forcibly rotated, and the lubricating properties of the accommodating parts such as the disc spring and the rotational force applying member are improved. Wear of parts can be minimized, and the cost of the valve rotator can be reduced.
(Claims 1 and 2).

(C) According to the first and second aspects of the present invention, the lateral movement of the valve spring is regulated, and the valve spring expands and contracts in a stable manner. Is done.

(D) According to the third aspect of the present invention, the manufacturing process of the rotator body is simplified, so that the manufacturing cost is reduced.

[Brief description of the drawings]

FIG. 1 is a central longitudinal sectional front view showing a main part of a valve train including a first embodiment of the present invention.

FIG. 2 is a central vertical sectional front view showing a main part of a valve gear including the second embodiment.

FIG. 3 is a partially cutaway front view showing a main part of a valve gear including a conventional valve rotator.

FIG. 4 is an enlarged vertical sectional side view taken along line AA in FIG. 3;

[Explanation of symbols]

 (1) Engine valve (1a) Shaft (2) Annular groove (3) Cotter (5) Concave groove (6) Coil spring (8) Valve spring (9) Disc spring (10) Rotator body (10a) Outward flange ( 10b) Tube part (10c) Body part (11) Snap ring (13) Cylinder head (14) Valve guide (15) Spring receiver (16) Disc spring (17) Rotator body (17a) Body (17b) Housing recess ( 17c) Bend (17d) Guide tube

Claims (3)

(57) [Claims] A plurality of or upwardly extending annular grooves extending on the same circumference are formed on the lower surface of an outward flange of a rotator body fixed to the shaft end of an engine valve that faces vertically. The lower surface of the rotating force applying member housed in the groove so as to be movable or tiltable is brought into contact with the upper surface of the disc spring, and the lower part of the lower surface of the disc spring is pressed against the upper end of the valve spring. And a downwardly directed cylindrical portion at the outer peripheral end of the outward flange.
Wherein the upper end of the valve spring is accommodated in the cylindrical portion . 2. A plurality of or circumferentially arranged annular grooves arranged in a circumferential direction on an upper surface of an outward flange of a rotator body provided in a through portion of a shaft portion of an engine valve in a cylinder head so as not to rotate around an axis. And the upper surface of the rotational force applying member housed in the groove so as to be movable or tiltable is brought into contact with the lower surface of the disc spring and the upper surface of the disc spring is formed.
Of the portion of the upper, upper end is pressed against the lower end of the supported valve spring by the spring bearing integral with the engine valve, the
When the body and the guide cylinder facing upward are provided inside and outside of the outward flange
Both are provided at the upper end of the body portion with an outside for preventing the disc spring from falling off.
And a lower end of a valve spring inside the guide tube.
A valve rotator for an internal combustion engine, wherein a portion is located . 3. The valve rotator for an internal combustion engine according to claim 2 , wherein the rotator body is formed by pressing a thin steel plate.