JPH09303379A - Switching element - Google Patents

Abstract

(57) [Summary] [Problem] Conventionally, for example, since a torsion coil spring is used as an opening / closing element for opening and closing a folded portion in a mobile phone, there is a problem that it is difficult to downsize the folded portion. A linear spring (1) made of a superelastic alloy and a spring buckling prevention tubular body (2) arranged on the outer periphery of the spring, the spring (1) and the spring buckling prevention tubular body (2). Is integrated only at both ends 3 and is a spring buckling prevention tubular body 2
The twisting allowance portion 4 is formed at the middle portion in the longitudinal direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an opening / closing part used for a cover opening / closing part of a mobile phone having a cover for protecting a main body folding part and a push button of a mobile phone whose size is reduced by folding a main body. It is related to the element.

[0002]

2. Description of the Related Art For example, one of the development goals of a mobile phone is to reduce the size and weight. Since the mobile phone itself has the function of a receiver, the microphone and the speaker need to have a certain length. Therefore, as a means of downsizing, we developed a mobile phone that has a folding part between the microphone and the speaker, folds it down when carrying it to make it compact, and opens the folding part during a call to secure the distance between the microphone and the speaker. Has been done. A structure has also been developed in which a microphone is attached to the cover for protecting the push button and the microphone is opened and closed.

Conventionally, a torsion coil spring has been used as an opening / closing element for opening and closing a folding portion or a cover in a mobile phone as described above.

[0004]

However, when the twisting coil spring is used to open and close the folding portion or the cover, a considerably large twisting coil spring is required, and the folding portion and the opening and closing portion of the cover are downsized. There was a problem that it was difficult.

[0005]

SUMMARY OF THE INVENTION The present invention provides an opening / closing element that solves the above-mentioned problems, and has a structure of a linear spring made of a superelastic alloy and a spring seat arranged on the outer periphery of the spring. The spring and the spring buckling prevention tubular body are integrated only at both ends, and the spring buckling prevention tubular body is allowed to be twisted in the middle portion in the longitudinal direction. It is characterized in that a portion is formed.

[0006] A linear spring made of a superelastic alloy does not cause a slip even if an excessive strain exceeding the yield point is applied by an external force due to stress-induced martensitic transformation associated with the yield. It returns to its original shape.
Since the strain at this time is as high as 8% and a large rotational force and a wide rotational stroke can be obtained, it can be sufficiently used as a spring for an opening / closing element. Further, since the spring buckling prevention tubular body is arranged on the outer periphery of the linear spring made of a superelastic alloy, the linear spring does not warp in a bow shape and buckle. Furthermore, since the spring and the spring buckling prevention tubular body are integrated only at both ends, and the spring buckling prevention tubular body is formed with a twisting allowance portion in the longitudinal middle portion, The spring can be easily twisted by rotating one end of the.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 shows a first embodiment of an opening / closing element according to the present invention, in which 1 is a linear spring made of a superelastic alloy and 2 is a spring buckling prevention tubular body. Spring 1
Is made of an alloy based on nickel-titanium and has a predetermined length. The outer periphery of the spring 1 in the longitudinal direction is covered with a spring buckling prevention cylindrical body 2. The spring buckling prevention tubular body 2 is formed of a metal tube, a plastic tube, or the like, and the spring 1 and the spring buckling prevention tubular body 2 are integrated only at both ends 3. This spring buckling prevention tubular body 2 is
A twisting allowance portion 4 is formed at a middle portion in the longitudinal direction. The twisting allowance portion 4 in the embodiment is formed by cutting off a part of the spring buckling prevention tubular body 2. For this reason, the spring buckling prevention tubular body 2 is divided into two parts. Reference numeral 5 denotes a protective cylinder that loosely covers the outer circumference of the spring buckling prevention cylindrical body 2. When such a protection cylinder 5 is used, the buckling of the spring can be prevented more effectively, and the torsion allowance portion 4 can be protected.

When one end of the switching element is fixed and the other end is rotated about the longitudinal direction of the spring 1, a linear spring made of a superelastic alloy is twisted about the longitudinal direction. At this time, since the torsion allowance portion 4 is formed in the spring buckling prevention tubular body 2, the spring buckling prevention tubular body 2 does not hinder the torsion of the linear spring. When the torsional force is removed from the spring, the spring automatically returns to its original shape.

Although the case where the protective cylinder 5 is provided has been described in the above embodiment, the protective cylinder 5 may not be provided.

FIG. 2 shows another embodiment of the present invention. What is different from the above-mentioned embodiment is that a heat-shrinkable protective cylinder 5 is put on the outer circumference of the spring buckling prevention cylindrical body 2. This is the point of using a tube. The heat-shrinkable tube is attached to the outer periphery of the spring buckling prevention tubular body 2 so as to be in close contact with it.

With this structure, when the linear spring made of the twisted superelastic alloy returns to its original shape,
Since an appropriate frictional force is generated between the spring buckling prevention tubular body 2 and the heat-shrinkable tube, it is possible to reduce the rotation speed when the spring returns to its original shape.

A similar effect can be obtained by using a rubber tube instead of the heat-shrinkable tube.

FIG. 3 shows another embodiment of the present invention. The difference from the above-described embodiment is that the torsion-allowing portions (two positions in the longitudinal direction of the spring buckling preventing tubular body 2 ( (Not shown) are provided to separate the spring buckling prevention tubular body 2 into three points and 2
This is the point where the flexible protective cover 6 is attached to the twisting allowance portion 4 at some places.

FIG. 4 shows still another embodiment of the present invention. The difference from the embodiment shown in FIG. 3 is that it is provided at two locations in the longitudinal direction of the spring buckling prevention tubular body 2. The point is that the coil-shaped connecting body 7 and the friction generating body 8 are attached to the twisting permissible portion 4. The coil-shaped connecting body 7 is arranged in a compressed state, which causes a repulsive force. This coiled body 7
Friction generators 8 are arranged at both ends of the. The friction generator 8 is arranged in a state where two disc bodies are in surface contact with each other, and one side 8A is fixed to the coil-shaped connecting body 7,
The other side 8B is fixed to the spring buckling prevention tubular body 2.

As described above, by using the coil-shaped connecting body 7 and the friction generating body 8, when the linear spring made of the twisted superelastic alloy returns to its original shape, the friction generating body 8 is rubbed. Since the force is generated, there is an effect that the rotation speed when the spring returns to the original shape can be reduced.

[0016]

【Example】

(Example 1) A superelastic alloy having a diameter of 0.6 mm was heated to 500 ° C.
50m in length after memory heat treatment in linear shape at the temperature
I cut it into m and made one linear spring made of superelastic alloy. Further, a spring buckling prevention tubular body made of sus304 having an outer diameter of 1.5 mm, an inner diameter of 0.7 mm and a length of 50 mm was prepared. The central portion of this spring buckling prevention tubular body was divided into two parts, and a twist allowing portion was formed in the central portion. next,
Insert a straight spring inside the spring buckling prevention cylinder,
The both ends of the spring buckling prevention tubular body were integrated by pressing the both ends of the spring buckling prevention tubular body with a thickness of 1 mm by pressing. The switching element having the above structure was attached to the folding portion 11 of the dummy model 10 of the mobile phone shown in FIG. The 11A side is the fixed side and the 11B side is the rotating side. The lid 12 of this dummy model 10 is in a state of being opened at an angle of 140 °. After closing the lid 12 of the dummy model 10 by hand, when releasing the hand, the 140
Automatically instantly opened to an angle of °. This opening and closing operation 1
After going through 10,000 times, the opening and closing angle remains 140 °,
No deterioration of characteristics was observed.

Example 2 A superelastic alloy having a diameter of 0.3 mm was subjected to a memory heat treatment in a linear shape at a temperature of 500 ° C., and then cut into a length of 30 mm to form a linear spring made of the superelastic alloy. I made three. Further, the outer diameter is 2.0 mm, the inner diameter is 1.5 mm, and the length is 3 having the same composition as the above superelastic alloy.
A cylindrical body for preventing spring buckling, which was 0 mm and knurled at both ends of 5 mm, was prepared. The central portion of this spring buckling prevention tubular body was divided into two parts, and a twist allowing portion was formed in the central portion. Next, three linear springs were inserted into the spring buckling prevention tubular body, and both ends 5 mm of the spring buckling prevention tubular body were inserted.
Was melted by laser welding to integrate the three springs with both ends of the spring buckling prevention tubular body. Further, the outer circumference of the spring buckling prevention cylindrical body covers the twisting allowance portion, and has an inner diameter of 1.8 mm,
A silicon rubber tube having a thickness of 0.3 mm and a length of 20 mm was attached. The opening / closing element having the above-described configuration is used as the folding portion 16 of the dummy model 15 of the two-fold type mobile phone shown in FIG.
Attached to. The 16A side is the fixed side and the 16B side is the rotating side. The lid 17 of the dummy model 15 is in a state in which an angle of 180 ° is opened. The lid 17 of this dummy model 15
After closing, the hand was released, and it slowly opened smoothly at an angle of 180 °.

(Example 3) A superelastic alloy having a diameter of 0.6 mm was subjected to a memory heat treatment in a linear shape at a temperature of 500 ° C and then cut into a length of 50 mm to form a linear spring made of the superelastic alloy. I made one. Further, a spring buckling prevention tubular body made of sus304 having an outer diameter of 2.5 mm, an inner diameter of 0.7 mm and a length of 36 mm was prepared. This spring buckling prevention tubular body was divided into three equal parts and twisted at two places to form an allowable portion. 2.5 mm outer diameter at the two twistable positions
The coil-shaped connected body was placed in a compressed state, and friction generators having an outer diameter of 2.5 mm were placed at both ends of the coil-shaped connected body. The friction generator is formed by arranging two disc bodies in surface contact with each other. One side is fixed to the coil-shaped coupling body and the other side is fixed to the spring buckling prevention tubular body. . Next, a linear spring is inserted inside the spring buckling prevention tubular body, and the spring buckling prevention tubular body (including the coil-shaped connecting body and the friction generating body in the middle) is compressed to 50 mm. Then, both ends 5 mm were compressed to a thickness of 2 mm by a press to integrate the spring and both ends of the spring buckling prevention tubular body. The switching element having the above structure was attached to the folding portion 11 of the dummy model 10 of the mobile phone shown in FIG. 11A side is the fixed side,
The 11B side is the rotating side. This dummy model 10 lid 1
No. 2 is in an opened state of 140 °. After closing the lid 12 of the dummy model 10 by hand and then releasing the hand, the dummy model 10 was automatically opened at a slow speed up to an angle of 140 ° in the set state.

In each of the above-mentioned embodiments, the case where the present invention is used in the folding portion of the mobile phone is shown, but the present invention can be widely used not only in the mobile phone but also in the opening / closing portion where the opening / closing operation is repeated. . Further, the spring buckling prevention tubular body may have a C-shaped cross section or the like instead of the cylindrical cross section. Further, any means can be used as a means for reducing the rotation speed when the linear spring made of the twisted superelastic alloy returns to its original shape, and is limited to the above-mentioned respective embodiments. Of course, it is not a thing.

[0020]

As described above, the switching element according to the present invention comprises the linear spring made of a superelastic alloy and the spring buckling prevention cylindrical body arranged on the outer periphery of the spring. Since the spring and the spring buckling prevention tubular body are integrated only at both ends, and the spring buckling prevention tubular body is formed with the twisting allowance portion in the middle portion in the longitudinal direction. It can be miniaturized and can withstand repeated use sufficiently.

[Brief description of drawings]

FIG. 1 is a partially cutaway front view showing an embodiment of the present invention.

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

FIG. 3 is a front view showing still another embodiment of the present invention.

FIG. 4 is a perspective view showing still another embodiment of the present invention.

FIG. 5 is a perspective view of a dummy model of a mobile phone.

FIG. 6 is a perspective view of another dummy model of the mobile phone.

[Explanation of symbols]

 1 Linear spring made of superelastic alloy 2 Cylindrical body for preventing spring buckling 3 Both ends 4 Twisting allowance part 5 Protective cylinder 6 Flexible protective cover 7 Coil-shaped connecting body 8 Friction generator

Claims (1)

[Claims] 1. A linear spring made of a superelastic alloy and a spring buckling prevention tubular body arranged on the outer periphery of the spring, wherein the spring and the spring buckling prevention tubular body are at both ends. An opening / closing element characterized in that the tubular body for preventing spring buckling has a twist allowing portion formed at an intermediate portion in the longitudinal direction, which is integrated only by the portion.