JPH02304228A - Spring seat member for coil spring - Google Patents

Abstract

PURPOSE:To obtain a high performance spring device capable of reducing to a weight and increasing a speed by forming channels engaged with the end parts of an element wire of a coil spring so as to form planes locked to the end parts of the coil spring and being orthogonal to the winding axis of the spring. CONSTITUTION:Spring seats 2 formed of relatively light different members are attached to the end parts 1a, 1b of open ends. Namely, each spring seat 2 is made of synthetic resin or light alloy such as aluminum, formed in a ring shape, and a spiral slant 3 matching a lead angle of the coil end part is formed in the outer peripheral part thereof. And the terminal of each slant 3 stops at a channel 4 depressedly provided in the outer peripheral surface of the spring seat 2. In this way, respective outer end parts 1a, 1b of a valve spring are locked to the slants 3, and the terminal parts 1c of a coil element wire are received in the channels 4, and therewith, engagement of respective outer end parts 1a, 1b of the valve spring 1 with the spring seats 2 is held.

Description

[Detailed Description of the Invention] [Object of the Invention] <Industrial Application Field> The present invention is applicable to movable members that perform reciprocating motion, such as suspension systems for vehicles or valve spring devices for internal combustion engines. The present invention relates to a spring seat member for forming a flat surface perpendicular to the axial direction at the end of an open-end coil spring used in a spring device for imparting elastic restoring force.

<Prior Art> In order to avoid curving of the winding shaft of a compression coil spring, the ends of the spring are sometimes finished flat to form a seat. In spring devices that require particularly high operating accuracy, it is customary to use a closed-end coil spring in which only the end portion is tightly wound and the end surface is ground.

<Problems to be Solved by the Invention> However, the tightly wound portion does not contribute to the effective number of turns of the spring, but rather has the disadvantage of contributing to an increase in the weight of the spring itself or the spring device. In particular, for spring devices used in devices that perform high-speed motion such as the valve train of a piston-type internal combustion engine, it is desirable that the mass of the end of the coil spring that moves together with the end of the valve stem is as small as possible. An increase in the weight of this part is not desirable for promoting high-speed operation.

The present invention was made to solve these problems, and its main purpose is to realize a high-performance spring device that is lightweight and can achieve even higher speeds. An object of the present invention is to provide a spring seat member for a coil spring that can be used.

[Structure of the Invention] <Means for Solving the Problems> According to the present invention, the present invention provides a spring device for applying an elastic restoring force to a movable member that is to perform reciprocating motion. A groove is formed to engage with the end portion of the strand of the coil spring in order to form a plane that is substantially perpendicular to the winding axis of the spring by being engaged with the end portion of the open-end coil spring. This is achieved by providing a spring seat member having the following properties.

<Function> In this way, it is possible to provide a spring seat member that can be reliably attached to the end of the spring while minimizing the engagement with the wire. Therefore, it is possible to reduce the weight of the end portion of the compression coil spring.

<Embodiments> Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows a valve spring with a spring seat member according to the invention attached to each end thereof, for application, for example, to a valve train of an internal combustion engine. This valve spring 1 is configured as an open-end coil spring which is wound at equal pitches and is made by grinding the outer ends 1a and 1b of strands flat.

Now, generally each end of a conventional valve spring is closed-ended and further ground to make each end flat (J I 52704). Furthermore, in the case of devices that do not particularly like bending of the winding shaft, it is customary for the tightly wound portion at the end to be approximately 1.5 turns, but this portion not only does not contribute to the effective number of turns of the spring. , resulting in an increase in the mass of the moving parts. Therefore, in the present invention, a spring seat 2 formed of a relatively lightweight separate member is attached to the open end ends 1a and 1b.

As shown in FIGS. 2a and 2b, the spring seat 2 is made of synthetic resin or a light alloy such as aluminum, and has a ring shape. A spiral slope 3 is formed corresponding to the slope. The slope 3 ends at a groove 4 recessed in the outer peripheral surface of the spring seat 2. In this way, each outer end 1aφ1b of the valve spring 1 is engaged with this slope 3, and the terminal end 1c of the coil wire is received in the groove 4, so that each outer end 1aφ1b of the valve spring 1 - The engagement between 1b and spring seat 2 is maintained.

FIG. 3 shows, as another embodiment, a state in which a spring seat 2 is attached to a valve spring 31 made of a two-step unequal pitch coil spring. The valve spring 31 is loosely wound on the free end side 31a and tightly wound on the base end side 31b. At the same time, the free end side 31
A has an open end and is fitted with the same spring seat 2 as shown in FIG. 1, and a proximal end 31b has a closed end and is ground flat. Thereby, the spring seat on the base end side 31b is omitted. Particularly when used in valve gears, the influence of the mass on the proximal end side is extremely small, and the increase in weight due to closed ends is not a major problem.In addition, in the case of coils made of steel, it is possible to Also, there is no problem of wear.

The above-mentioned slopes and grooves are indicated by reference numeral 4 in FIGS. 4a and 4b.
As shown at 3.44, it may be formed on the inner peripheral side of the ring-shaped spring seat 42. In addition, when the end of the valve spring is open-end and unground, as shown in FIGS. 5a and 5b, a spiral slope 53 is formed inside the spring seat 52.
Although it is necessary to make the width of the groove 54 continuous to the valve spring 51 equal to the wire diameter of the valve spring 51, it can basically be implemented in the same manner.

Incidentally, the slope or groove for locking the end of the spring is not limited to the type formed on the outer circumferential side or the inner circumferential side of the spring seat member as shown in each of the above embodiments.
As shown in FIGS. 6a and 6b, it can also be formed on the axial end surface of the spring seat member 62. In this case, the inner and outer peripheral surfaces of the valve spring 1 are restrained by the groove 64. Alternatively, a hole 65 with a closed top surface may be formed in the extension of the groove 64, thereby holding the terminal end 1c of the valve spring 1.

Furthermore, as shown in FIGS. 7a and 7b, the spring seat member 72 is provided with a surface S1 on which the outer peripheral side of the valve spring 1 engages, or as shown in FIGS. 8a and 8b,
It can be implemented in various ways, such as forming a surface S2 on the spring seat member 82 to which the inner peripheral side of the valve spring 1 is engaged.

FIG. 9 shows how the valve spring device is used, taking as an example the valve spring 1 and spring seat 2 shown in FIG.
0 controls the intake of air-fuel mixture and the discharge of combustion gas as an intake valve or an exhaust valve by cooperating with a valve seat 11 that opens into the combustion chamber.

The stem portion 12 of the valve 10 slides into a stem guide 13 that is press-fitted into the cylinder head.
The upper spring seat 2 is locked to the outermost end of the spring seat 2 via a spring retainer 14 and an annular spring retainer 15. On the other hand, the lower spring seat 2 is supported by an annular flat surface formed at a portion of the cylinder head from which the stem guide 13 protrudes, via a washer 16 made of metal or heat-resistant resin. Note that reference numeral 17 is a stem seal for preventing oil from entering the combustion chamber.

Now, one end of a rocker arm 18 is in contact with the outer end of the stem portion 12, and the other end of the rocker arm 18 is supported by the cylinder head via a hydraulic lash adjuster 19. Further, the cam contour surface 20a of the camshaft 20 is in contact with the upper surface of the intermediate portion of the rocker arm 18. Therefore, in this embodiment, when the camshaft 20 is rotationally driven, the rocker arm 18 is rotated through the cam contour surface 20a.
is tilted downward about the lash adjuster 19, and the stem portion 12 of the valve 11 is driven downward in FIG. 9 against the biasing force of the valve spring 1, and the valve 10 is opened.

In the above embodiments, the present invention is applied to a valve train for an internal combustion engine, but the present invention is not limited to applications for internal combustion engines, but is applicable to movable members that perform reciprocating motion, such as suspension systems for vehicles. This can be applied to any mechanical device that has a configuration that provides elastic restoring force to the object.

[Effects of the Invention] As described above, according to the present invention, it is possible to reduce the size of the spring seat member and suitably reduce the mass of the moving part of the spring device, thereby further increasing the operating speed of the mechanical device. It can be achieved. Furthermore, since a damping effect based on the viscoelastic properties of the spring seat can be obtained, the overall effect can be extremely significant in increasing the speed of mechanical devices such as internal combustion engines.

[Brief explanation of drawings]

FIG. 1 is a side view showing an example of a valve spring and a spring seat used in a spring device according to the invention configured as a valve spring device. FIG. 2a is a plan view of the spring seat, FIG. 2b is a sectional view of the spring seat, and FIG. 3 is a side view showing another aspect of the valve spring and the spring seat. Figures 4a to 8a are plan views showing modified embodiments of the spring seat, and Figures 4b to 8b are sectional views corresponding to these. FIG. 9 is a partial sectional view showing an example in which the valve spring device shown in FIG. 1 is applied to a valve mechanism.

Claims (3)

[Claims] (1) A plane that is engaged with the end of an open-end coil spring used in a spring device to apply an elastic restoring force to a movable member that is to perform reciprocating motion, and that is approximately perpendicular to the winding axis of the spring. A spring seat member for a coil spring, characterized in that a groove is formed to engage with an end portion of a wire of the coil spring to form a groove. (2) A spring seat member for a coil spring according to claim 1, characterized in that it is made of a synthetic resin material. (3) A spring seat member for a coil spring according to claim 1, characterized in that it is made of aluminum or an aluminum alloy.