JP2002129919A - Spring retainer for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a retainer which can form its positioning projection for the spring simply and with high accuracy and without decreasing its strength, and can form its whole part of it using such a simple forming method as stamping process keeping high rigidity and considering a biggest possible weight reduction. SOLUTION: Two stripes of the inner and the outer slits 4, 5 are made in several places in the periphery direction of the spring retaining flange 3 and swell the middle part of the slits to the spring retaining surface side 3a and forms the positioning projection 6 for the valve spring 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spring retainer used for a valve train of an internal combustion engine, and more particularly to a structure of a positioning projection for a valve spring formed on a spring receiving flange thereof.

[0002]

2. Description of the Related Art A valve retainer for an internal combustion engine uses a spring retainer which is fixed to an upper end portion of an engine valve via a pair of cotters and supports an upper end of a valve spring.

[0003] The spring retainer is generally formed by forging a steel material. Since the whole is formed to be thick, the spring retainer is heavy and obstructs in reducing the inertial mass of the valve train. Has become.

A conventional spring retainer which addresses such a problem is disclosed in, for example, Japanese Utility Model Laid-Open Publication No. Sho 62-185807.
Japanese Patent Application Laid-Open No. 62-185808 and Japanese Utility Model Application Laid-Open Publication No. Sho 62-185808 disclose spring retainers made of sheet metal to reduce the weight.

[0005] In these sheet metal spring retainers, by utilizing the characteristics of the sheet metal, the spring positioning protrusions can be easily formed by stamping out by pressing.

[0006]

However, the positioning projection disclosed in Japanese Utility Model Laid-Open Publication No. Sho 62-185807 described above is obtained by simply punching a sheet metal downward.
There is a problem that it is not possible to expect high-precision processing in terms of strength, and the positioning projections disclosed in Japanese Utility Model Application Laid-Open No. 62-185808 are formed by cutting and raising a sheet metal. It is a cantilevered support, and has problems such as not only being weak in strength but also not being able to expect high accuracy.

Further, a large pressing force is applied to the tapered cylindrical portion of the spring retainer, into which the cotter is fitted, so as to expand the diameter of the cotter, and a large upward force by the valve spring is applied to the spring receiving flange. Since the reaction force acts repeatedly, high rigidity is required especially for a spring retainer mounted on an automobile engine driven at high speed and under high load.

In the case of a structure in which a spring receiving flange is simply formed integrally with the upper end of a cylindrical portion, as in the above-described conventional spring retainer made of sheet metal, high rigidity cannot be obtained, and the lower end of the cylindrical portion has a cotter. Therefore, there is a risk that the diameter of the spring receiving member will be reduced and the spring receiving flange will be deformed upward.

In order to increase rigidity in the above-mentioned conventional structure, it is necessary to increase the thickness of the material.

Further, as in the case of the above-mentioned conventional spring retainer, a plurality of circumferential portions of the spring receiving flange are cut off and bent downward, and the bent piece is used as a guide portion for positioning the valve spring. In addition, not only the rigidity of the spring receiving flange is further reduced, but also the stress is concentrated on the cut corner due to the notch, which may cause a crack or the like.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and allows a positioning projection for a spring to be easily formed with high precision without reducing strength, while maintaining high rigidity. It is an object of the present invention to provide a spring retainer for an internal combustion engine which can be easily formed as a whole by pressing a sheet metal or the like, and can reduce the weight as much as possible.

[0012]

According to the present invention, the above-mentioned problem is solved as follows. (1) A spring retainer for an internal combustion engine including a cylindrical portion having a tapered hole at the center in which a pair of cotters can be fitted, and a spring receiving flange connected to the cylindrical portion and supporting an upper end of a valve spring. At two or more places in the circumferential direction of the spring receiving flange, two inner and outer cuts are provided, and an intermediate portion thereof is bulged toward the spring receiving surface side, and both ends are connected to the spring receiving flange. Forming positioning projections.

(2) In the above item (1), a spring receiving flange is integrally connected to the lower end of the cylindrical portion which is the reduced diameter end of the tapered hole.

(3) In the above item (1) or (2), the cylindrical portion and the spring receiving flange are integrally formed by sheet metal.

(4) In any one of the above items (1) to (3), of the two cuts, at least the cut in contact with the valve spring has an arc shape concentric with the center of the tapered hole.

(5) In any one of the above items (1) to (4), the shape of the positioning projection as viewed from the center of the tapered hole is as follows:
It is almost V-shaped.

(6) In any one of the above items (1) to (4), the shape of the positioning projection as viewed from the center of the tapered hole is as follows:
It has a substantially upward U-shape.

(7) In any one of the above items (1) to (4), the shape of the positioning projection as viewed from the center of the tapered hole is as follows:
The shape is a downward convex arc.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a first embodiment of the present invention, and FIG. 2 is a front elevational view in the center in a state of being assembled to a valve operating mechanism.

In both figures, a spring retainer (1)
Consists of a tapered cylindrical portion (2) that expands upward and a spring receiving flange (3) that is continuously provided outward at the lower end of the cylindrical portion (2). , And are integrally formed by sheet metal processing, that is, pressing, deep drawing, or the like.

At a plurality of places in the circumferential direction of the spring receiving flange (3) (in this example, four places, but three places or five places)
May be more than two places).
The arcuate cuts (4) and (5) of the strip are provided, and the middle part thereof is bulged toward the spring receiving surface (3a), which is the lower surface, so as to form a substantially upward U-shape, so that both ends of the spring are cut. Valve spring described later, connected to the receiving flange (3)
A positioning projection (6) for (9) is formed.

The spring retainer (1) has a cylindrical portion (2).
The inward bead (7a) of the pair of cotters (7) (7) fitted in the tapered hole (2a) in the inside is fitted into the annular groove (8a) at the shaft end of the engine valve (8). As a result, it is fixed substantially integrally therewith.

When the cotter (7) is fitted,
The lower end is located at the same position as the upper surface of the spring receiving flange (3) or slightly lower than it.
With this configuration, when a large pressing force is applied to the cotter (7), a part of the downward pulling force acting on the cotter (7) is received by the spring receiving flange (3), so that the cylindrical portion ( Only in the case of 2), it is prevented that the diameter of the reduced diameter portion on the lower end side is increased.

The upper end of the valve spring (9) is pressed against the lower surface of the spring receiving flange (3) outside the positioning projection (6), whereby the spring retainer (1) and the engine valve (8) are It is always biased upward.

The positioning protrusion (6) is brought into contact with the outer peripheral edge thereof by the inner peripheral surface of the upper end portion of the valve spring (9).
It is greatly displaced outward and the spring receiving flange
(3) Prevent it from coming off. Since the outer peripheral edge of the positioning projection (6) is formed in an arc shape by the outer cut (5), the outer peripheral edge uniformly contacts the inner peripheral surface of the valve spring (9) and does not hit one side.

The inner edge of the positioning projection 6 that does not contact the valve spring 9 and the inner notch 4 may be formed in a straight line. Positioning protrusion
In some cases, a valve spring (9) is fitted inside (6) or two valve springs are concentrically arranged inside and outside of the positioning projection (6). Preferably, the inner and outer edges of the positioning projections (6) that come into contact with the valve spring, and the cuts (4) and (5) are arc-shaped.

In the first embodiment, the cylindrical portion (2)
Since the large diameter spring receiving flange (3) is continuously provided at the lower end of the cylindrical portion (2), the strength of the lower end of the cylindrical portion (2) is lower than that of the conventional one having the spring receiving flange at the upper end of the cylindrical portion (2). And the stiffness is significantly increased. Therefore, even if it is made of relatively thin sheet metal, the lower end of the cylindrical portion (2) is not likely to be enlarged by the cotter (7), and the sinking is prevented.

As a result, it is not necessary to increase the thickness of the cylindrical portion (2) to increase the rigidity as in the prior art, and the weight of the spring retainer (1) can be reduced.

FIG. 3 shows a second embodiment of the present invention. In this example, a spring receiving flange (3) is continuously provided at the upper end of a cylindrical portion (2) having a tapered hole (2a). In addition, the shape of the positioning projection (6) viewed from the center side of the tapered hole (2a) can be substantially reduced by swelling the middle portion of the inner and outer cuts (4) and (5) downward substantially in a V shape. It is V-shaped. Other configurations are the same as those of the first embodiment, and the same members are denoted by the same reference numerals and are not illustrated, and detailed description is omitted (the same applies to the third embodiment below). .

FIG. 4 shows a third embodiment of the present invention. In this example, the middle portions of the inner and outer cuts (4) and (5) are expanded downward in a substantially semicircular shape. Accordingly, the shape of the positioning projection (6) as viewed from the center side of the tapered hole (2a) is a downwardly projecting arc, and similarly to the second embodiment, the cylindrical portion (2) having the tapered hole (2a). A spring receiving flange (3) is connected to the upper end of (2).

In the second and third embodiments, since both ends of the positioning projection (6) in the circumferential direction are connected to the spring receiving flange (3) to form a double-sided support structure, the positioning projection (6) is provided. High strength and rigidity, and positioning protrusion
(6) is in contact with the valve spring (9) not at the flat surface of the sheet metal but at the side end perpendicular to the flat surface, so that the strength and rigidity can be further improved, and the notch (4)
By providing (5), the same effects as in the first embodiment, such as the position accuracy of the positioning projection (6) can be improved, can be obtained.

[0032]

According to the present invention, the following effects can be obtained. According to the invention described in claim 1, both ends of the positioning projection in the circumferential direction are connected to the spring receiving flange,
Since it has a two-sided support structure, the strength and rigidity of the positioning projections are high, and the positioning projections contact the valve spring at the side end orthogonal to the flat surface of the sheet metal instead of the flat surface, so that the strength and rigidity are further improved. Improvement can be achieved. Also, since the spring receiving flange is provided with two inner and outer cuts and the intermediate portion thereof is bulged to one side to form the positioning protrusion, the positioning protrusion can be formed easily with high precision and by pressing. it can.

According to the second aspect of the present invention, by providing the spring receiving flange at the lower end of the cylindrical portion which is the reduced diameter end of the tapered hole, the strength and rigidity of the lower end of the cylindrical portion are significantly increased,
The cotter relatively sinks due to plastic deformation such that the portion expands in diameter, and the spring receiving surface of the spring receiving flange fluctuates upward, adversely affecting engine performance, or causing the cotter to relatively move. It can surely be prevented from coming off. Further, since the strength and rigidity are increased, the thickness of the material can be reduced to a minimum and the length of the cylindrical portion can be reduced, so that the weight of the spring retainer can be reduced.

According to the third aspect of the present invention, the thin spring retainer can be easily formed by press working or the like, and its weight can be further reduced.

According to the fourth aspect of the present invention, since the positioning projection uniformly contacts the valve spring and does not hit one side, damage due to abrasion or the like is small and durability is improved.

According to the fifth, sixth and seventh aspects of the present invention,
The position determining projection having high strength and rigidity can be easily formed by press working.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a first embodiment of the present invention.

FIG. 2 is also a front view in the center longitudinal section in a state where it is assembled to a valve operating mechanism.

FIG. 3 is a central longitudinal sectional front view showing a state in which a second embodiment of the present invention is assembled to a valve operating mechanism.

FIG. 4 is a front view in central section showing a state in which a third embodiment of the present invention is assembled to a valve train.

[Explanation of symbols]

 (1) Spring retainer (2) Cylindrical part (2a) Tapered hole (3) Spring receiving flange (3a) Spring receiving surface (4) (5) Cut (6) Positioning protrusion (7) Cotta (7a) Bead (8) Engine valve (8a) Annular groove (9) Valve spring

Claims (7)

[Claims] 1. A spring for an internal combustion engine, comprising: a tubular portion having a tapered hole at the center in which a pair of cotters can be fitted; and a spring receiving flange connected to the tubular portion and supporting an upper end of a valve spring. In the retainer, a valve spring is provided in which two inner and outer cuts are provided at a plurality of locations in the circumferential direction of the spring receiving flange, and an intermediate portion thereof is bulged toward the spring receiving surface, and both ends are connected to the spring receiving flange. A spring retainer for an internal combustion engine, wherein a positioning projection for the internal combustion engine is formed. 2. A lower end of a cylindrical portion which is a reduced diameter end of the tapered hole,
2. The spring retainer for an internal combustion engine according to claim 1, wherein the spring receiving flange is integrally connected. 3. The spring retainer for an internal combustion engine according to claim 1, wherein the cylindrical portion and the spring receiving flange are integrally formed by sheet metal. 4. The spring retainer for an internal combustion engine according to claim 1, wherein at least one of the two cuts that is in contact with the valve spring has an arc shape concentric with the center of the tapered hole. 5. The spring retainer for an internal combustion engine according to claim 1, wherein the shape of the positioning projection as viewed from the center of the tapered hole is substantially V-shaped. 6. The spring retainer for an internal combustion engine according to claim 1, wherein the shape of the positioning projection as viewed from the center side of the tapered hole is substantially upward U-shaped. 7. The spring retainer for an internal combustion engine according to claim 1, wherein the shape of the positioning projection as viewed from the center of the tapered hole is a downwardly projecting arc.