JPH07281137A - Production of spectacle frame - Google Patents

Abstract

PURPOSE:To provide a process for producing a spectacle frame which is resilient and is capable of long maintaining comfortable wearability. CONSTITUTION:Temples 1 of this spectacle frame are formed of a superelastic alloy subjected to work hardening. Gripping force forming parts 3 exclusive of hinge parts 2 of these temples l are heat treated at 250 to 550 deg.C. As a result, the hinge parts 2 and gripping force forming parts 3 of the temples l vary in strength and spring characteristic. The spectacle frame which does not loosen even after long-term use, is resilient and is capable of long maintaining the comfortable wearability is obtd. Since there is no need for increasing the sectional area of the hinge parts 2, the aesthetic appearance of the frame is maintained without impairment.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method of manufacturing an improved eyeglass frame.

[0002]

2. Description of the Related Art The temples of spectacle frames are often made of a material having a good spring property so that the temples can be fitted properly along the face. In recent years, it has been proposed to utilize the large strain recovery characteristic of Ni—Ti alloys, so-called superelasticity, for this purpose. When using such superelastic alloys for temples, it is possible to obtain excellent wearing comfort and wearability due to the recovery characteristics of several percent due to superelasticity and the recovery characteristics with constant stress like rubber. Is known to bring. As a spectacle frame using a superelastic alloy for temples, for example, a spectacle frame having a temple formed of a metal material having a superelastic effect at room temperature (Japanese Patent Laid-Open No. 56-95215) is disclosed.

[0003]

However, the above-mentioned eyeglass frame is designed to make the entire temple superelastic by strong cold working or quenching. When the entire temple is superelastic in this way, the hinge portion is processed. However, there is a drawback in that the periphery of the hinge is easily broken due to the influence of heat when brazing or welding the hinge. . In such a case, a method of increasing the cross-sectional area of the temple near the hinge can be considered, but in order to bring out a sufficient effect, the cross-sectional area must be made larger than necessary, which is not aesthetically preferable. As a spectacle frame in consideration of aesthetics, "a spectacle frame at least a part of which is made of a metal material that has been age-hardened or quenched and tempered (Japanese Patent Laid-Open No. 55-2276)" is disclosed. But,
This invention is intended to make a spectacle frame thin and slim by using a metal material reinforced by age hardening or quenching and tempering, and the metal material used is an age hardening alloy such as beryllium copper. The wearability obtained by the elastic alloy is not considered at all. The present invention is
Manufacture of spectacle frames that combine aesthetics and wearability by providing supple superelastic characteristics only in the necessary parts of the temples of the spectacle frames using a cold-work-hardened superelastic alloy such as NiTi alloy The purpose is to provide a method.

[0004]

According to the present invention, a temple of an eyeglass frame is formed of a superelastic alloy which is work-hardened by cold working, and the gripping force forming portion excluding the hinge portion of the temple has a temperature of 250 to 550 ° C. The method for manufacturing an eyeglass frame is characterized in that it is heat-treated at a temperature of 1 to give a superelastic effect.

Here, the superelastic alloy includes Cu-Zn and Cu-Zn-X in addition to the alloy mainly composed of NiTi intermetallic compound.
(X = Si, Sn, Al, etc.), Cu-Al-Ni, A
u-Cd, Ag-Cd, Ni-Al, Cu-Au-Z
Although Ni, Cu-Sn, etc. are used, NiTi-based alloys having good characteristics such as corrosion resistance are often used. The present invention forms a temple of a spectacle frame from the work-hardened superelastic alloy, and heat-treats the gripping force forming portion of the temple excluding the hinge portion at a temperature of 250 to 550 ° C at which superelastic characteristics are obtained. A method of manufacturing an eyeglass frame in which superelasticity is imparted only to the gripping force forming portion.

[0006]

According to the present invention, the hinge portion of the temple of the eyeglass frame is made of a work-hardened material, the hinge portion can be easily formed and processed, and the heat effect in brazing or welding is small,
In addition, since the hinge part is hard, it does not sag due to many years of use and does not loosen, resulting in good wearability. On the other hand, the gripping force forming part, excluding the hinge part, has a supple superelastic characteristic. Then, the elasticity of superelasticity works, and you can get a spectacle frame that fits perfectly and softly. As mentioned above, since the hinge part is not heat-treated, it is hard and has little bending. Therefore, the cross-sectional area of the hinge portion is not increased and the appearance is not spoiled. Such an effect is obtained by heat-treating only the gripping force forming portion excluding the hinge portion. The heat treatment temperature may be set to an appropriate temperature and time depending on the type of superelastic alloy. In the case of NiTi alloy, it is 250 to 550 ℃, 10 minutes to
One hour is appropriate, and good superelastic properties cannot be obtained outside this range. Further, the heating method may be a method capable of locally heating such as salt bath or gas flame heating. The gripping force forming portion means a portion where the gripping force is formed in contact with the face.

[0007]

EXAMPLE An example of the present invention will be described below. Ni50.7at
The Ni-Ti alloy with the remaining% Ti was work-hardened sufficiently by cold drawing, roll rolling and cold press forming to prepare the temple 1 shown in FIG. Next, after forming the hinge portion 2 on the temple by pressing and cutting, the gripping force forming portion 3 was heated in a salt bath at 400 ° C. for 20 minutes to impart superelasticity characteristics. After this, a synthetic resin cover 4 is attached to the tip.
Was fitted to form an eyeglass frame. This spectacle frame does not open the temple in spite of being tested several thousand times and removed, and the hinge part has the same cross-sectional area as before, but the hinge part also slides and rotates. It has been found that the gripping force forming part is smooth and has no looseness, the gripping force forming part is flexible and comfortable to wear, and the flexibility is not deteriorated. The heat treatment conditions differ depending on the type of superelastic alloy, but good properties can be obtained by selecting appropriate heat treatment conditions.

[0008]

As described above, according to the present invention,
A hinge and a gripping force forming portion of the temple have different strengths and spring properties, and a spectacle frame that does not loosen even after long-term use and is flexible and comfortable to wear can be obtained for a long time. Moreover, since it is not necessary to increase the cross-sectional area of the hinge portion, the appearance is not spoiled.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of an eyeglass frame obtained according to the present invention.

[Explanation of symbols]

 1-Temple 2--Hinge section 3-Grip force forming section 4--Cover

Claims (1)

[Claims] 1. A temple of an eyeglass frame is formed of a superelastic alloy work-hardened by cold working, and the gripping force forming portion of the temple excluding the hinge portion is heat-treated at a temperature of 250 to 550 ° C. to obtain superelasticity. A method for manufacturing a spectacle hood, which is characterized by imparting an effect.