JP3326518B2 - spring - 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 synthetic resin spring developed for a mattress and usable as other various cushioning elements and elastic elements.

[0002]

2. Description of the Related Art Mattresses used for bedding such as beds have a large number of metal coil springs, torsion bars and the like uniformly distributed in a flat plate shape. Along with joining in a plane,
A spring whose outer peripheral edge is surrounded by a wire or the like is used. Such a spring generally has a complicated structure and poor productivity, and is heavy in weight, requires a great deal of labor for handling during transportation and the like, and generates an unpleasant squeaky sound when used. There were problems such as occurrence of cracks and poor consistency with the fiber material portion such as side ground.

[0003] Therefore, as a substitute for the conventional metal spring, a plastic spring that is lightweight, quiet, and has good productivity is being developed. In the case of this plastic spring, it is similar to other plastic products. Because it is possible to form a spring with a completely different shape from the conventional one, it is possible to obtain excellent mechanical characteristics by its shape effect. When the elastic deformation reaches its limit, there is a concern that the supporting state becomes unstable or the material is broken due to insufficient strength of the material itself.

[0004]

SUMMARY OF THE INVENTION In view of the above problems of the prior art, the present invention is light and quiet, and allows a large amount of elastic deformation as compared with the size of a spring. It is an object of the present invention to obtain a spring whose support state is stable against an excessive compressive load and which is hardly broken.

[0005]

A plurality of annular members which are integrally formed of a synthetic resin material and which are disposed at appropriate intervals and have the same axis and are arranged in parallel, and a plurality of annular members are arranged at a plurality of positions. The elastic connecting member is arranged along a virtual cylindrical surface formed by each of the annular members, and the spring has an inverted U-shape curved in the circumferential direction of the annular member. The diameter of the annular member is made different between adjacent annular members, and one end and the other end of the elastic connecting member are provided shifted in the radial direction of the annular member so that they do not overlap in the direction of expansion and contraction of the spring. At the same time, the elastic connecting members protrude parallel to the annular member on the outer peripheral side of the relatively small-diameter annular member or the inner peripheral side of the relatively large-diameter annular member, and are located on both sides of the annular member. Mutual And a limit plate for preventing Wataru.

[0006]

1 to 3 show a representative embodiment of the spring of the present invention, which will be described below with reference to the drawings.

In the drawing, a spring 1 of the present invention comprises a central annular member 2 and two annular members 3 and 3 which are spaced apart from each other at upper and lower sides and have the same axial center C and are arranged in parallel.
And a plurality of inverted U-shaped elastic connecting members 4 for connecting the respective annular members 2, 3, 3 to each other at three locations on the circumference.

Among the annular members 2, 3, 3, the upper and lower annular members 3, 3 have the same diameter r3, and the central annular member 2 has the same diameter r2 as the upper and lower annular members 3, 3. It is set to be relatively smaller than that.

As shown in FIG. 2, each of the elastic connecting members 4 is arranged along a substantially cylindrical virtual cylindrical surface 5 formed by the respective annular members 2, 3, and 3. ,
The one end 41 and the other end 42 continuous with 3, 3 are radially shifted so as not to overlap in the axial direction C (the direction of expansion and contraction of the spring 1) which is the vertical direction in the figure.

When an excessive compressive load is applied to the outer periphery near the connecting position of the one end portions 41 of the elastic connecting members 4 and 4 located on both the upper and lower sides of the central annular member 2, the elastic connecting members are connected to each other. A limiting plate 21 is formed to prevent the other end portions 42, 42 of the members 4, 4 from abutting and interfering with each other.
The upper and lower annular members 3 and 3 are provided with an arch-shaped notch on the inner peripheral side where the curved portion 43 of the elastic connecting member 4 overlaps in the axial direction C to prevent the members from contacting each other. 3
3 is formed.

The spring 1 is integrally formed entirely of a synthetic resin material, and is basically formed using a mold. In the case of the illustrated spring, the core is divided into two parts in the vertical direction in the figure and the slide-type cavity is divided into three parts, so that the moldability is good. As the resin material used for the spring 1, a material having excellent bending strength and particularly strong against repeated bending stress is preferable.
Polyamide or polyacetal resin is used.

When a compressive load (equally distributed load) is applied to the spring 1 configured as described above, each elastic connecting member 4 is bent in a direction to decrease the interval between the inverted U-shapes, and the spring 1 As a whole, it is compressed by an elastic deformation amount corresponding to the above-mentioned compressive load to be in an equilibrium state.

At this time, as shown in FIG. 2, the one end 41 and the other end 42 of the elastic connecting member 4 are arranged radially shifted from each other, so that they do not come into contact with each other. This allows the spring 1 to allow a larger amount of elastic deformation than a simple cylindrical spring in which the diameters of the annular members 2, 3, and 3 are equal, and the one end 4
It is possible to prevent noise caused by contact and interference between the first and second ends 42.

When an excessive compressive load P exceeding the limit of the shape elastic deformation is applied to the spring 1, as shown in FIG. 4, each of the curved portions 43, 43 abuts against the central annular member 2 respectively, and the other end portions 42, 42 of the elastic connecting members 4, 4 abut against the flat upper and lower surfaces of the limiting plate 21, thereby further elastic deformation. Limited.

Accordingly, even if the spring 1 is bent three-dimensionally by bending and twisting the other end portions 42, 42 of the elastic connecting members 4, 4, the other end portions 42, 4
The corners of the two are prevented from abutting against each other or being staggered between the outside and the inside, so that the support state is prevented from becoming unstable or damaged, and a stable support state is obtained. .

The limiting plate 21 may be formed over a wider range, and may be formed in a flange shape over the entire circumference of the annular member 2. When connecting a plurality of springs 1 of the same shape, a limiting plate for preventing the end portions 41, 41 of the elastic connecting members 4, 4 from coming into contact with each other and preventing interference is provided on the inner peripheral side of the annular member 3 having a large diameter. It may be formed.

The upper and lower annular members 3 of each spring 1 are arranged so that a large number of the springs 1 are held between the layers of a pair of upper and lower net-like elastic planar members made of synthetic resin. , 3 are fixed to the net-like elastic flat member and integrated into a mattress spring made of only synthetic resin, and the mattress spring is provided with a web, a heat insulating material, a permeable member such as a breathable sheet or the like. A mattress can be formed by stacking body layers and covering them with side lands. The mattress constructed as described above suppresses unnecessary vibration and swaying at the time of turning over and the like by a buffering and damping action by the viscoelasticity of the synthetic resin material, and has the same effect as a conventional metal mattress spring. It is quiet without any squeaking noise, lightweight, and easy to handle during transportation.

In each of the above embodiments, a case has been described in which the continuous spring 1 is constituted by three annular members 2, 3, 3 and two upper and lower elastic connecting members 4 connecting the annular members. However, the number of steps of the annular member and the elastic connecting member can be appropriately set, and in addition to the conical shape, a conical shape or a drum shape in which the diameter of the central annular member 2 is larger than the diameter of the annular members 3 and 3 at the upper and lower ends. You can also. Furthermore, two or more springs 1 may be stacked and connected and used integrally by means such as adhesion, fusion or fitting. Further, the inverted U-shaped elastic connecting members 4 may be arranged as a pair of two members arranged in mirror symmetry with each other, or may be provided at three or more locations in the circumferential direction. Further, two or more portions having different patterns may be formed in the length direction of the spring by combining the arrangement patterns of two or more elastic connecting members.

[0019]

Since the spring of the present invention is configured as described above, the following effects can be obtained.

The whole is integrally formed of a synthetic resin material,
A plurality of annular members arranged at equal intervals and having the same axis and arranged in parallel, and an elastic connecting member for connecting the annular members to each other at a plurality of locations, the elastic connecting member includes:
In an inverted U-shaped spring arranged along a virtual cylindrical surface formed by each annular member and curved in the circumferential direction of the annular member, the diameter of the annular member is made different between adjacent annular members, In addition, one end and the other end of the elastic connecting member are provided so as to be shifted in the radial direction of the annular member so that they do not overlap in the direction of expansion and contraction of the spring. Since a limiting plate is provided on the inner peripheral side of the large-diameter annular member so as to extend parallel to the annular member and to prevent interference between the elastic connecting members located on both sides of the annular member. The contact between one end and the other end of the elastic connecting member is prevented, a large amount of elastic deformation can be tolerated compared to the size of the spring, and even when an excessive compressive load is applied, the elastic connecting member Mutual Contact or interference and destabilization of the supporting state by it, or breakage of the spring is prevented,
A stable support state is obtained. It is much lighter than conventional metal coil springs, torsion bars, etc., and has a very large elastic force per weight of the synthetic resin material used. Further, since the production cost can be suppressed by forming a molded product, it can be expected to be widely used not only for mattresses but also as various elastic elements and cushioning elements.

[Brief description of the drawings]

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

FIG. 2 is a front view showing an embodiment of the spring of the present invention.

FIG. 3 is a partially cutaway plan view showing an embodiment of the spring of the present invention.

FIG. 4 is a partially cutaway front view showing the elastically deformed state of the spring according to the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Spring 2, 3 Annular member 4 Elastic connection member 21 Limit plate 33 Notch 41 One end 42 Other end 43 Curved part

Claims (1)

(57) [Claims] A plurality of annular members which are integrally formed of a synthetic resin material as a whole, are disposed at appropriate intervals, are arranged in parallel with the same axial center, and are elastically connecting the annular members to each other at a plurality of locations. A connecting member, wherein the elastic connecting member is disposed along a virtual cylindrical surface formed by each of the annular members, and is a U-shaped spring curved in the circumferential direction of the annular member. Is different between adjacent annular members, and provided with one end and the other end of the elastic connecting member shifted in the radial direction of the annular member so that they do not overlap in the direction of expansion and contraction of the spring, Projecting parallel to the annular member on the outer peripheral side of the relatively small annular member or the inner peripheral side of the relatively large annular member,
A spring provided with limiting plates for preventing interference between elastic connecting members located on both sides of the annular member.