JPH0519211A - Rim of glasses - Google Patents

Abstract

PURPOSE:To absorb elongation and contraction of plastic lenses of glasses due to air temp., and to solve problems such as distortion or dropping of lenses. CONSTITUTION:A Rim 2 of glasses is made of such material having elasticity and is formed to have a V-shaped groove with smaller angle of V-shape but larger depth compared to a conventional rim. By fitting a lens 1 of glasses to this rim 2 in a manner that the groove of the rim 2 is rather widened, expansion and contraction of the lens can be absorbed by opening and closing of the groove of the rim 2. As for a material for the rim 2, metal or alloy having necessary elasticity is used, and higher effect can be obtd. when superelastic metal such as a titanium alloy is used. It is effective to use such rims having thinner side walls of the groove or partly notched rim to improve elasticity of the rim groove.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rim for spectacles in consideration of expansion and contraction of lenses.

[0002]

2. Description of the Related Art Conventionally, lenses used for spectacles are classified into two types, glass type lenses and plastic type lenses. At present, plastic-based lenses are more widely used because they are lighter than glass. The rim of the eyeglasses on which the lens is attached is generally made of plastic or metal. FIG. 9 shows a cross-sectional view of a rim of conventional metal eyeglasses. As shown in (a) to (f) of FIG. 9, the outer shape is different, but the inner shape into which the lens is fitted has almost the same shape. The bevel angle of the groove in which the lens is fitted, which is indicated by the arrow in the figure, is usually 110 to 115 degrees. The edge of the lens fitted in the groove of the bevel is cut at an angle of about 120 degrees which is almost the same as the bevel angle or slightly larger. Figure 10 shows how the lens fits into the rim of a normal groove.
FIG. 11 is an explanatory view showing how a lens is fitted into a rim having a round groove, and a rim with a bevel angle of 110 to 115 degrees is fitted with a lens whose edge is cut to about 120 degrees.

As described above, conventionally, spectacles are assembled so that there is no gap between the lens and the rim by making the bevel angle of the rim groove and the bevel angle of the lens edge, the rim size and the lens size substantially equal. It was

[0004]

Although the plastic lenses such as CR-39 and polycarbonate have excellent optical properties, they have a drawback that they expand and contract greatly with temperature. Actual expansion and contraction will differ slightly depending on the lens shape, size, and material of the lens, but within the normally used temperature range ± 0.3 to 0.4 mm
There is some expansion and contraction.

On the other hand, in the case of a metal rim, the expansion and contraction due to the temperature difference is much smaller than that of a plastic lens. At high temperatures, the plastic lens expands greatly, but the degree of expansion of the metal rim is small. Therefore, the rim exerts an unreasonable force on the lens, which may cause distortion of the lens. Further, at a low temperature, the lens largely contracts, so that a gap may be formed between the lens and the rim, or in a severe case, the lens may come off the rim. It is an object of the present invention to provide a metal rim that does not cause distortion or falling out of a plastic lens due to changes in temperature.

[0006]

[Means for Solving the Problems] The following means are used to solve the problem that a plastic lens expands and contracts due to the temperature and causes distortion and dropout of the lens. A material having elasticity is used as the material of the rim, and the shape of the groove of the rim is smaller than that of the conventional rim, the bevel angle is small, and the bevel depth is large. A normal lens cut into an edge of about 120 degrees is attached to this rim with the groove of the rim slightly widened.

The expansion of the lens generated under high temperature is absorbed by the groove of the rim expanding. At low temperatures, the rim's groove, which has expanded lens contraction, returns to its original narrow angle and absorbs it. By using such a rim, it is possible to prevent the lens from being distorted or dropped. As a material for the rim, any metal capable of obtaining necessary elasticity such as nickel silver and titanium alloy can be used.

From the viewpoint of shape, it is effective to use a rim groove having a thin side surface or a part of the rim groove in order to further enhance elasticity.

[0009]

The rim of the present invention will be described with reference to the drawings. FIG. 1 shows an example of a normal groove rim 2 of the present invention, and FIG. 2 shows an example of a round groove rim 3. In either case, a material having elasticity such as a titanium alloy is used for the rims 2 and 3. If the material lacks elasticity, or if you want to further increase the elasticity of the rim groove, make the side surface of the rim groove thin or a part of it removed as shown by the shaded area in both figures. Is effective.

The shape of the groove of the rim is 110-1 in the conventional rim.
While the bevel angle is 15 degrees, the bevel angle is small and the bevel depth is large. About 1 for this rim 2, 3
The lens 1 cut at the edge with an angle of 20 degrees is mounted as shown in FIGS. 1 and 2 with the groove of the rim slightly widened.

In the state where the angle of the groove is widened by the fitting of the lens, the force of increasing the peripheral diameter of the rim edge works. If the rim itself cannot accommodate changes in the rim edge due to stretching, make a break in the rim as necessary to create an escape area. Figure 3
[Fig. 4] is an enlarged view of a cut provided on the rim. A cut 4 is made on one side of the rim 2 to make it easier to widen the groove. Such a break may be provided anywhere, but it is not noticeable when provided on the back surface of the bridge portion or the brooch portion. FIG. 4 shows an enlarged view of the cut 4 of the bridge portion 5, and FIG. 5 shows an enlarged view of the cut 4 of the broach portion 6. When viewed from the back surface of the frame provided with the cuts, it becomes as shown in FIG.

FIG. 1 is an explanatory view showing how a lens is fitted on the rim of the present invention. The bevel angle of the rim is smaller than the bevel angle of the lens. Lens 1 as shown by the arrow
Is pressed against the rim 2, the side wall of the rim 2 elastically deforms to support the lens. In order to promote elastic deformation of the rim side wall, there is also a method of removing the portion shown by the hatched portion of the rim. FIG. 2 is an explanatory view of a rim having another sectional shape, but it is the same as the case of FIG.

At high temperature, since it has elasticity, the groove of the rim further expands to absorb the expansion of the lens. At low temperatures, the slightly widened rim's groove attempts to return to absorb lens contraction. By using such a rim, it is possible to absorb the expansion and contraction of the lens of ± 0.3 to 0.4 mm and prevent the distortion and the detachment of the lens.

[0014]

EXAMPLE An example of the rim of the present invention is shown in FIG. The lens is mounted on the rim of the ordinary groove of the present invention. The rim is made of titanium alloy. Before mounting, the rim 2 of the present invention
Has a groove with a bevel angle of 90 degrees, and the bevel depth is lens 1
Much larger than. Further, the lens 1 has a rim processed to 120 degrees. Further, a recess is formed on the side surface of the groove in order to enhance elasticity. When the lens is attached to this rim, the bevel of the groove is 115 mm according to the shape of the lens as shown in FIG.
Spreads to a degree. Such deformation of the rim can cope with expansion and contraction of the plastic lens.

[0015]

As described above, by using a material having elasticity for the rim, the bevel angle can be made small and the bevel depth can be made large so that the expansion and contraction of the lens can be absorbed, and the detachment and distortion of the lens can be eliminated. There is an effect that can be done.

[Brief description of drawings]

FIG. 1 is an explanatory view showing mounting of a lens on a rim of the present invention.

FIG. 2 is an explanatory view showing the mounting of the lens on the rim of the present invention.

FIG. 3 is an enlarged view of a cut provided on the rim of the present invention.

FIG. 4 is an enlarged view of a cut provided in a bridge portion of the rim of the present invention.

FIG. 5 is an enlarged view of a cut provided in a broach portion of the rim of the present invention.

FIG. 6 is a rear view of a cut provided on the rim of the present invention.

FIG. 7 is an explanatory diagram of mounting of the rim according to the embodiment of this invention.

FIG. 8 is an explanatory diagram of mounting of the rim according to the embodiment of this invention.

FIG. 9 is a cross-sectional view of various conventional rims.

FIG. 10 is an explanatory view of mounting a lens on a conventional rim.

FIG. 11 is an explanatory view of mounting a lens on a conventional rim.

[Explanation of symbols]

1 lens 2 Rim of the present invention 3 Rim of the present invention 4 breaks 5 bridge 6 brooches 7 Temple 12 Conventional rim 13 Conventional rim

Claims (2)

[Claims] 1. A bevel angle is at least 20 ° or more smaller than a bevel angle of an eyeglass lens to be fitted, a bevel depth is larger than a bevel depth of the eyeglass lens, and a rim groove is made of an elastic material which is elastically deformable to open and close. The rim of the eyeglasses characterized by being. 2. The rim for spectacles according to claim 1, wherein a rim edge is provided with a cut.