JPH0928416A - Coil spring - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent an ornamental bar and a clip bar to be pressed in opening and closing directions by a coil spring from being mutually twisted in the tie bar of an ornament. SOLUTION: Acting end parts 16 and 17 respectively continuously attached on both ends of this coil spring 11 are not simply extended in the circumferential direction of a coil as before but are bent in a crank shape and positioned at the approximate center of the axial direction of the coil. Since an application point by the acting end parts 16 and 17 is not shifted from the center of the coil, a moment for twisting the ornamental bar 13 and the clip bar 14 is not generated.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to the shape of a coil spring.

[0002]

2. Description of the Related Art A coil spring is used as a tension spring that exerts a tensile force in the axial direction of a coil or as a compression spring that exerts a compressive force in the axial direction of a coil, and also in the direction of opening and closing a target member. It is used as an opening / closing spring for urging. Conventional examples of coil springs used as the opening / closing springs are shown in FIGS. 4 and 5 show a tie bar 2 which is a decorative article using the coil spring 1. FIG. 4 is a sectional view and FIG. 5 is an overall view. The tie bar 2 is for fastening the end of the tied tie to the shirt, and has a decoration bar 3 on the front side of the tie and a clip bar 4 on the back side of the tie. Both bars 3 and 4 are pin-coupled and can be opened and closed. A coil spring 1 is provided around the pin coupling shaft 5. Working ends 6 and 7 are continuously provided at both ends of the coil of the coil spring 1, and the working ends 6 and 7 bias the decoration bar 3 and the clip bar 4 in the closing direction. At this time, the urging force F is applied to the decoration bar 3 and the clip bar 4. Such coil springs as opening / closing springs are used in various products other than tie bars. For example, it is also used for the hair clip 8 shown in FIG.

[0003]

However, in the conventional coil spring 1, when used as an opening / closing spring, two members of the product, that is, the decorative bar 3 in the above-mentioned conventional example are used.
The biasing force F applied to the clip bar 4 causes a twisted state. That is, the two members are not perfectly parallel to each other. This will be described in detail with reference to FIGS. As shown in FIG. 4, as a reaction of the biasing force F, the biasing force F is also applied to the coil spring itself. The urging force F is
The coil spring 1 works at a distance r from the center of the coil spring 1 along the axial direction of the coil. Therefore, the moment M = Fr to rotate is applied to the coil spring 1 in the vertical cross section as shown in FIG. Therefore, the coil spring rotates to some extent. And as a result of this rotation,
The working ends 6 and 7 of the coil spring 1 produce a one-sided contact with the two members. That is, the urging force F acts not in a direction perpendicular to the pin coupling axis 5 but in a slightly oblique direction. F1 acting in this diagonal direction is in a plane as shown in FIG. 5 (a view of FIG. 5 viewed from the IV direction is FIG. 4),
A force of F ₁ sin Θ ₁ is generated.

Considering either one of the two members, this F ₁ sin Θ ₁ does not work as a pair, but works alone. Moreover, it works away from the pin axis to some extent. If this distance is r ₁ , the coil spring produces a rotational moment M1 = F ₁ sin Θ ₁ r ₁ even in the plane. In the above-mentioned conventional example, this rotation moment causes the clip bar 4 to rotate in a plane with respect to the decoration bar 3, and the bars 3 and 4 are twisted. The twist angle Θ ₂ in the twisted state is determined by the size of the gap existing between the coil spring 1 and the pin coupling shaft 5. And
Even if the twist angle Θ ₂ is small, if the two members of the product are sufficiently long, the deviation δ between the two tips caused by the twist becomes large (FIG. 6). Such a deviation δ is a defective product depending on the product, and even if it is not a defective product, the appearance is significantly impaired. This appearance greatly influences the value of the product, especially when the product is a decorative item. The present invention has been made to solve the above problems, and an object thereof is to provide a coil spring that does not cause a twisted state in two members of a product used as an opening / closing spring. And

[0005]

In order to achieve the above-mentioned object, the invention of claim 1 is such that the working ends, which are continuously provided at both ends of the coil, are located substantially at the center in the axial direction of the coil. This is a coil spring.
The invention of claim 2 is the coil spring according to claim 1, which is further used for a clip portion of a decorative article. The invention according to claim 3 is the coil spring according to claim 2, wherein the ornament is a tie bar.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to FIG.
3 to FIG. The coil spring 11 of the present invention is used for, for example, a tie bar 12 which is a decorative article, and gives a biasing force for biasing two members constituting the tie bar 12, that is, the decorative bar 13 and the clip bar 14 in a direction to close each other. The clip bar 14 is formed with teeth 18 for increasing friction so that it does not slide down along the tie. The working ends 16 and 17 respectively provided at both ends of the coil may be bent in a crank shape and positioned substantially at the center in the axial direction of the coil, instead of extending directly in the circumferential direction of the coil as in the conventional case. Yes (at the bottom of Figure 1). Alternatively, more complicatedly, it may be bent in a U shape and then bent in a crank shape so as to be positioned substantially at the center in the axial direction of the coil (upper end in FIG. 1).

If such a coil spring is provided,
As shown in FIG. 2, the action ends 16 and 17 for applying the urging force F to the two members, that is, the decoration bar 13 and the clip bar 14.
Are located substantially in the center of the coil in the axial direction. Therefore, it does not work at a position away from the center of the coil as in the conventional case. Therefore, in the vertical cross section as shown in FIG. 2, a moment for rotating the coil spring 1 is not generated unlike the conventional case. Therefore, the working ends 16 and 17 of the coil spring 1 do not hit the decorative bar 13 or the clip bar 14 evenly. Since there is no one-sided contact,
(See) does not cause the force in. Therefore, the decoration bar 13 and the clip bar 14 are in the plane.
There is also no moment to rotate the two in the direction of twisting each other. Therefore, without causing a twist angle,
The ends of the decoration bar 13 and the clip bar 14 cannot be displaced. The coil spring 11 as described above can be used not only for the tie bar 12 as an ornament as shown in FIG. 3 but also for the hair clip as shown in FIG. In addition, two members are pin-coupled, and a coil spring is provided around the axis of this pin coupling for all products that give a biasing force in the opening / closing direction.
The present invention can be implemented.

[0008]

As described above, according to the first aspect of the invention, since the working end of the coil is located substantially at the center in the axial direction of the coil, the coil spring itself, or the opening / closing direction by the coil spring. It is possible to prevent the member that receives the biasing force from rotating and twisting. When this coil spring is used for a clip portion of a decorative article, the appearance can be improved by eliminating the twisted state.

[Brief description of drawings]

FIG. 1 is a perspective view of a coil spring according to an embodiment of the present invention.

FIG. 2 is a sectional view of a main part of a tie bar to which a coil spring according to another embodiment of the present invention is attached.

3 is an overall perspective view of the tie bar of FIG.

FIG. 4 is a cross-sectional view showing a problem of the conventional technique.

5 is an overall plan view of FIG.

FIG. 6 is a perspective view showing another conventional example.

[Explanation of symbols]

 11 coil 12 tie bar 13 decorative bar 14 clip bar 16, 17 working end

Claims (3)

[Claims] 1. A coil spring, characterized in that the working ends, which are continuously provided at both ends of the coil, are located substantially at the center in the axial direction of the coil. 2. The coil spring according to claim 1, which is used for a clip portion of a decorative article. 3. The coil spring according to claim 2, wherein the ornament is a tie bar.