JPH0664262B2 - How to make brazed hinged pieces - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for manufacturing a brazed hinge piece.

[Conventional technology]

When the metal spectacle frame is largely disassembled, it is disassembled into a front frame and a temple, and the two are coupled with one left and right hinge screws to be assembled into the spectacle frame. The hinge is a pair of hinge pieces and 1
One of the pair of hinge frames is brazed to the front frame frame or other spectacle frame member, and the other is brazed to the temple.

[Problems to be solved by the invention]

By the way, recently, thin spectacle frames have been favored, and the hinge frame is inevitably downsized. Therefore, the hinge frame made of the most common nickel silver (Cu-Zn-Ni alloy) has a problem in that it has insufficient strength and poor wear resistance after brazing.

The object of the present invention is to solve these problems.

[Means for solving problems]

The present inventors have studied the causes of insufficient strength and poor wear resistance, and as a result, the Vickers hardness (hereinafter abbreviated as HV) of the hinge piece due to the heat received during brazing is, for example, most commonly In the case of the nickel silver used, it has fallen to 100 or less, and therefore it is found that the strength is insufficient and the wear resistance is deteriorated.Therefore, in order to recover the hardness decrease due to brazing, the age hardening `` Precipitation hardenable metal "
I focused my research on.

As a result, the inventors have invented a method for producing a brazed hinge piece, which is characterized in that a hinge piece made of a solution-hardened precipitation-hardening metal is brazed to an eyeglass frame member and then age hardened. This is the first invention of the present invention.

Further, since the hinge piece is relatively small, the solution treatment can be performed simultaneously with the brazing by setting the brazing temperature to the solution treatment temperature. This is the second invention of the present invention.

[Action]

As used herein, the term "precipitation hardenable metal" means an alloy that is hardened and strengthened by solution treatment and subsequent aging treatment, and has a narrower meaning than the generally understood precipitation hardenable metal. As an example of such a precipitation hardenable metal, a beryllium copper alloy (Be content is 0.4 to 4%, other than copper, Co, N
i, Sn, Cr, etc.), copper titanium alloy, copper nickel manganese alloy such as Cu-20Ni-20Mn alloy, age hardening aluminum alloy such as JIS A6000 series and 7000 series alloy, age hardening stainless steel, for example JIS G SUS630
Examples include cobalt-based spring alloys such as Co-Ni-Cr-Mn-W alloy.

If this metal is subjected to solution treatment in advance and then subjected to aging treatment, hardness (which has a correlation with strength and serves as a measure of strength) is improved.

"Solution treatment" is a heat treatment that solidifies the alloy and then rapidly cools it to a supersaturated solid solution. Taking high-strength beryllium copper as an example, it is heated to a high temperature of 800 ° C. Then the solute component becomes a solid solution in the soft α phase,
Quenching from that temperature gives a supersaturated solid solution. This heat treatment is called solution treatment.

Then, the resulting supersaturated solid solution is heated to 200 to 500 ° C, especially 300 to 3
When heat-treated at a relatively low temperature of 50 ° C, precipitation of beryllium compounds occurs and the alloy becomes hard and strengthened. This heat treatment is called aging treatment (or (artificial) age hardening treatment). In this case, the aging treatment for heat treatment at a temperature ^* at which the alloy becomes the hardest is called proper aging treatment, and the aging treatment for heat treatment at a temperature higher than that temperature ^* is called overaging treatment.
^* Aging treatment in which heat treatment is performed at a lower temperature is called underaging treatment.

In the past, "precipitation hardenable metal" such as beryllium copper alloy was processed into solution, cold working, and aging processing into temples, which are one of the eyeglass frame members, and the hinge pieces were brazed to them. It has been reported. However, in this case, the aging treatment was not performed after the brazing, so that the hardness of the hinge piece after brazing was as low as HV = 120 or less.
Even with the most popular nickel-silver (Cu-Zn-Ni alloy) temples, the hardness of the brazing part and its vicinity is at most HV.
= 100.

On the other hand, the beryllium copper alloy, which is a typical example of the precipitation hardening metal used by the present inventor, has a tensile strength of about 140 kg / mm ² (HV = 400) due to the age hardening treatment after the solution treatment, which is This corresponds to about 3 to 4 times that of the white softening material.

In addition, in the state after the solution treatment, the precipitation hardenable metal is soft, so cold working ^*, for example, cold wire drawing is easy,
In this state, it is preferable to form a hinge frame. Cold working is a process in which work hardening occurs with plastic deformation and is called cold working.

As described above, the hinge piece is made of the armature, the temple, and the armature and the temple are integrated, and after brazing the hinge piece, it is brazed to a member for cutting the hinge piece and other spectacle frame members.
It is preferable that such a spectacle frame member also be made of a solution-hardened precipitation-hardening metal, like the hinge frame. The reason is that the thin eyeglass frame member also softens the brazing portion and its vicinity due to the heat received during brazing, and the strength tends to be insufficient. However, the eyeglass frame member may be made of a metal other than the precipitation hardenable metal, such as nickel silver (Cu-Zn-Ni alloy), stainless steel, or nickel-chromium alloy.

In the method of the present invention, the hinge frame and the spectacle frame member are brazed, but the temperature of brazing should be 700 to 850 ° C. in the case of the second invention, for example, beryllium copper alloy. In the first invention, since the solution treatment has already been completed, the brazing temperature may be lower, and for example, in the case of beryllium copper alloy, 600 to 700 ° C is suitable. A suitable brazing time is, for example, 5 seconds or less for beryllium copper, and cooling after brazing should be fast.

In the case of the second invention, when the brazing is performed, the hinge piece and the “brazing portion of the spectacle frame member made of the precipitation hardening metal and its vicinity” become a soft α phase in which the solute component is solid-solved, and the brazing is performed. After the above, since the hinge frame and the spectacle frame member are relatively small and thin, they are naturally left to cool and the temperature rapidly drops, and the α phase eventually becomes a supersaturated solid solution. In this case, when the cooling is not sufficient, it is preferable to spray the cooled gas or water-cool to positively cool. Care should be taken not to obtain results such as annealing (furnace cooling) with this "brazing". If the result looks like annealing,
After that, the hardness is not improved even by aging treatment.

As described above, the age hardening treatment performed after brazing is heat treatment at a relatively low temperature of 200 to 500 ° C., particularly 300 to 350 ° C. for a beryllium copper alloy, which causes precipitation of a beryllium compound and makes the alloy hard. To be strengthened. As a result, the hardness of the hinge frame and "the brazing portion of the eyeglass frame member made of the precipitation hardening metal and its vicinity" is improved, and HV =
More than 200. If HV = 200 or more, the strength and wear resistance of the hinge piece are sufficient, and also when mechanical stress acts on the brazing part of the eyeglass frame member made of precipitation hardening metal and its vicinity. Deformation and damage are prevented.

Hereinafter, the present invention will be specifically described with reference to Examples, but the present invention is not limited thereto.

(Example 1) Production of hinge frame: A beryllium copper alloy (JIS C1720) φ4 mm round wire was prepared, and this was heated at 800 ° C for 30 minutes and then cooled with water to perform solution treatment (HV = 120). ).

Next, a cold-working process was performed to draw a special-shaped deformed wire. This resulted in HV = 220. After this, according to the usual method, cutting, cutting,
Processing such as drilling and screw cutting is performed, and one piece piece 1a (width 1 = 2.5 mm, piece thickness t = 0.9 mm) shown in FIG. 2 and two piece piece piece 1b (width piece 1 = width 1 = width t = 0.9 mm) shown in FIG. 2.5mm, frame thickness t
= 0.8 mm) was produced. Both of them were assembled with a hinge screw 2 shown in FIG. 4 to form a hinge.

The solution treatment may be performed after cold working or cutting, but the work efficiency is better if it is carried out with the round wire. Further, depending on the case, the hinge pieces 1a and 1b may be produced by casting.

Manufacture of eyeglass frame members: On the other hand, a beryllium copper alloy (JIS C1720) φ2.5 mm round wire was prepared, and this was heated to 800 ° C. for 30 minutes and then water-cooled for solution treatment (HV = 120). Then 100 mm
Cut to length.

The diameter of the cut round wire is reduced by cold working (swaging) (HV = 220), and the width l = the width of the armature 3a and subsequently the temple 3b is integrated by pressing.
2.5mm spectacle frame member 3 was manufactured (HV = 240).

The solution treatment may be performed after the cutting process, the swaging process or the pressing process, but the work efficiency is better if the solution treatment is performed with the round wire.

Brazing: As shown in FIG. 1, a hinge was placed on the spectacle frame member 3 via the brazing material piece 4 and brazing was performed.

The brazing was performed by using silver solder 3 (JIS BAg-1) and heating it from the hinge side to about 650 ° C. for about 2 seconds by high frequency induction heating. The brazing part was quenched after the heating was stopped. As a result, the brazing portions of the hinge frames 1a and 1b and the spectacle frame member 3 and their vicinity were softened to HV = 140.

Age hardening treatment: The brazed product was subjected to an appropriate aging treatment at 315 ° C for 2 hours. By this aging treatment, the hardness of the hinge frames 1a, 1b is increased to HV = 400, the hardness of the brazing portion of the spectacle frame member 3 and its vicinity is increased to HV = 400, and the other portions of the spectacle frame member 3 are HV = Improved to 450.

In this case, since the strength of the soldered portion of the temple 3b and its vicinity is lower than that of the other portions, it becomes easy to receive stress concentration, but in general, since the soldered portion of the temple 3b and its vicinity are thicker than other portions, this Don't worry.

If you want to increase the toughness of hinge pieces 1a and 1b,
Hardness is HV by overaging or underaging rather than proper aging
It may be reduced to about 250 to 350. However, if this is done, then the strength of the temple 3b becomes insufficient, so that the eyeglass frame member 3 should be pre-aged appropriately before brazing (HV
= 450), after brazing, under-aged the hinge frame 1a,
The hardness of 1b may be HV = 250 to 350.

Cutting: After the age hardening treatment, the eyeglass frame member 3 is cut at the position of the arrow X shown in FIG.
Divided into This allows the hinge to be opened and closed.

After the spectacle frame is completed, it will be 3 for fitting.
There is a case where a is bent, but in order to facilitate this, when it is desired to reduce the hardness of the end piece 3a,
Before brazing, the spectacle frame member 3 is cut to be divided into the armor 3a and the temple 3b, the former is subjected to preliminary overaging or complete annealing, and proper aging may be performed after brazing.

Aging treatment of beryllium copper alloy (JIS C1720) maximizes proper aging at 315 ° C. HV = 200-400 (Value not subjected to cold working after solution treatment, after cold working. Hardness is improved to HV = 200-450). A treatment temperature of at least 200 ° C is suitable, and hardness lower than that is not expected to improve hardness. At most 500
C is appropriate, and at higher temperatures, the effect of improving strength is similarly small.

Moreover, when a free-cutting beryllium copper alloy is used instead of the beryllium copper alloy (JIS C1720), the machining efficiency of the cutting process is improved. However, since this alloy contains several percent of lead, its wear resistance is slightly inferior.

(Example 2) Production of hinge pieces: Beryllium copper alloy (JIS C1720) φ4 mm round wire was prepared, and the hinge pieces 1a and 1b were produced in the same manner as in Example 1 without solution treatment. Then, it was assembled with the hinge screw 2 to form a hinge.

Production of eyeglass frame member: The same as in Example 1.

Brazing and solution treatment: Silver brazing (JIS BAg-6) was used, and a gas burner was applied from the hinge side to heat at about 800 ° C. for about 5 seconds. The brazed part should be cooled 40 minutes after 1 second by quenching after stopping heating.
It was below 0 ° C.

As a result, the hinge pieces 1a, 1b and the spectacle frame member 3 were solution treated, and HV = 120.

Age hardening treatment: The same as in Example 1.

Cutting: The same operation as in Example 1 was performed to obtain a brazed hinge frame.

Test Example: With respect to the hinge pieces of Examples 1 and 2, the temple 3b opening / closing test was performed 20,000 times, but no play was observed.

On the other hand, in the hinge frame made of nickel-white and having the same size and shape as those of Example 1, looseness was recognized in the opening / closing test of 5000 times.

After fixing the armor 3a, a bending load was applied in a direction perpendicular to the hinge opening / closing direction at a position 100mm away from the seam of the armor 3a and the temple 3b (referred to as a joint) on the temple 3b. At (2 kg · cm), 1a 'was bent and deformed by 10 °, but the hinges of Examples 1 and 2 were 800 g (8 kg
・ Cm) did not cause bending deformation.

The age-hardening treatments of Examples 1 and 2 were subjected to underaging treatment at 250 ° C. for 2 hours, and the bending test was conducted on the HV250 hinge. As a result, there was no bending deformation at 200 g and 500 g (5 kg · cm).
Deformed by 10 °.

〔The invention's effect〕

As described above, according to the present invention, the hinge piece made of the precipitation hardenable metal is solution-treated in advance, or solution treatment is performed at the same time as brazing, and the age hardening treatment is performed after brazing, so that the hardness is HV. = 200 or more, resulting in improved strength and wear resistance.

Up to now, no hinge piece with a hardness of HV = 200 or more has been reported.

[Brief description of drawings]

FIG. 1 is a perspective view showing a relationship between a hinge piece and a spectacle frame member when brazing in the first embodiment. 2 and 3 are perspective views of the hinge piece of the first embodiment. FIG. 4 is a perspective view of a hinge screw. [Explanation of symbols of main parts] 1a, 1b ... hinge frame 1a '... 1 piece frame root portion 2 ... hinge screw 3a ... Horoy (an example of eyeglass frame member) 3b ... temple (eyeglass frame member) Example) 4 ... brazing material

Claims (2)

[Claims] 1. A method for manufacturing a brazed hinge piece, which comprises subjecting a hinge piece made of a solution-treated precipitation-hardening metal to an eyeglass frame member and then subjecting it to an age hardening treatment. 2. A brazed hinge, wherein a hinge piece made of a precipitation-hardening metal is subjected to solution treatment at the same time as brazing when brazing the eyeglass frame member, and then age hardening treatment. How to make tops.