JPH09127265A - Wrist watch case with built-in reinforcing casing ring and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a wrist watch case which reduces material loss of the watch case of such noble metal element as gold, maintains strength and has high magnetism resistance. SOLUTION: In a wrist watch case 1 formed of noble metal element by electroforming, a groove 1b is provided inside the middle part, a back 1a is formed in a plate, and a casing ring 2 formed of pure iron on the inner surface of the back is arranged. The medium frame has a flat cut part 2a at 12 and 6 o'clock positions. By contacting the flat cut part 2 and the groove 1b, an eccentric screw 3 inserted in the casing ring 2 is fit in the groove 1b by rotating to fix the casing ring 2. By this constitution, material loss of noble metal is saved, strengthening is attained by putting the reinforcing ring, and the effect of external magnetism is avoided by using pure iron for the casing ring.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mainly relates to reinforcement of a wristwatch side using a precious metal.

[0002]

2. Description of the Related Art Conventionally, when a wristwatch is manufactured from a material such as a noble metal, forging is often performed.
In this case, a watch side with a heavy weight can be obtained without paying attention to the gold stitches, but this is a manufacturing method with a lot of material loss and a high cost. Therefore, in recent years, a rational manufacturing method using a thin plate (40/100 mm thickness or the like) by so-called drawing process with less material loss is being started. This thin plate drawing must be less material loss than the forging type, but in terms of strength retention,
A minimum thickness of 40/100 mm was necessary, and it was impossible to further reduce the thickness.

[0003]

From the viewpoint of resource saving and from the standpoint of providing users with inexpensive products, it is desirable to reduce the material loss of precious metals as much as possible. However, even if the wall thickness of the exterior is made thin, the function as a timepiece will be lost if the strength is insufficient. Therefore, it has been a problem to realize a thin precious metal timepiece that can maintain the strength.

[0004]

In order to solve the above-mentioned problems, the wristwatch side of the present invention, which is integrated with the case back, is integrally formed by electroforming of a precious metal material, and pure iron is formed on the inside of the case and the inside of the case back. The metal inner frame of No. 1 is engaged. The wristwatch side, which is integrally formed by electroforming, is thin, and by inserting a metal inner frame into the inner part of the inner case of the watch side, the strength due to the thinness, especially of the case It is possible to reinforce the lack of strength and obtain a wristwatch side that is practically durable.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The wristwatch side with a reinforced middle frame according to the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view of a main part of an integrally molded timepiece obtained by electroforming molding of the present invention. FIG. 2 is a plan view of a middle frame formed inside the case back.

As shown in FIG. 1, the watch side 1 has a back cover portion 1a.
It is united with. First, the master 20 on the timepiece side 1 is manufactured from a material having relatively good workability such as nickel-white material.
The shape of the master 20 is substantially the same as the desired shape. The almost target shape is the thickness (15 mm) for electroforming from the final precious metal watch side shape.
0 to 300 μm). As will be described below, electroforming is not performed on the inner surface of the back cover, so the outer diameter shape of the back cover 20a of the master 20 is finished to the inner diameter of the finished timepiece 1 side. Since the surface finish affects the surface finish of the next electroforming treatment (so-called thick plating) as it is, it is necessary to finish it carefully. The mask 2 is attached to the inner shape of the case back 20a of the master 20 on the watch side.
1 is formed and electrically inactivated.

After forming the mask 21 on the master 20,
The electroforming treatment (so-called thick plating) is performed under conditions set so that the thickness is 150 to 300 μm. On the inner surface side (upper side in the drawing) of the back cover portion 20a of the master 20, plating does not deposit due to the masking effect of the mask 21. That is, the deposition thickness of electroforming is controlled by a computer to form the watch side 1 of a gold alloy (18K) having a desired thickness (for example, 200 μm). Electroforming conditions are cyan solution,
The gold concentration is 15 g / liter, the silver concentration is 5 g / liter, potassium cyanide is 15 g / liter, the bath temperature is 45 ° C., the current density is 1.5 A / dm ² , and the deposition rate is 1.0 μm / min.

Then, the mask 21 is removed and the master 2
0 is corroded and removed with an acid solution such as nitric acid. Since there is no 18K deposition film on the inner surface side of the back cover 21a of the master 20, this portion becomes an opening when the base material is dissolved by acid treatment or the like. The timepiece side 1 thus obtained is formed of a noble metal film having a film thickness of 200 μm, and the timepiece side 1 other than the case back 1a has the hollow portion 4 shown in FIG. The hollow portion 4 is the master 20.
It corresponds to the shape of. Since the hollow layer does not exist in the back cover portion 1a due to the masking effect, it is a single plate. Due to this back cover reinforcement, the middle frame 2 of pure iron, which is relatively strong and has excellent magnetic resistance, is tightly engaged with the inside of the back cover portion 1a.

FIG. 2 is a plan view of the middle frame 2. The middle frame 2 is
The height between the dial plate 5 and the back cover portion 1a shown in FIG. 3 is set to be the height, and the saray portion 2a is provided at two positions of 12:00 and 6:00.
I made Further, as shown in FIG. 1, the groove portion 1 on the watch side 1
The middle frame 2 is arranged so that the saray portion 2a is engaged with b.
The eccentric screw 3 is inserted into the saray portion 2a and rotated, and the screw head of the eccentric screw 3 is inserted into the groove portion 1b.
Is fixed. The master groove 20b is formed in the master 20 so that the groove 1b is formed on the timepiece side 1.

As another embodiment, the back cover portion of the integrally molded timepiece obtained by electroforming molding is not made into a single plate by masking as in the above-mentioned embodiment, but the inner side is formed by lathe processing with an external chuck. The wall can be removed to form a single plate.

[0011]

EFFECTS OF THE INVENTION The integrally molded watch side obtained by electroforming as in the present invention has a high hardness, which is also a characteristic of deposited gold, and the strength is maintained even if it is thin, and the gold joint can be reduced. Moreover, since the middle frame is interposed, the drop impact resistance and waterproofness are compensated for, and the basic quality as a heavy-duty luxury watch is maintained. The inner frame is made of pure iron that allows magnetic force to pass through, so the inside of the watch is not affected by the magnetic force and the magnetism of the watch is improved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a main part of a timepiece side and a master according to the present invention.

FIG. 2 is a plan view of a reinforcing middle frame according to the present invention.

FIG. 3 is a cross-sectional view of an essential part when a timepiece is assembled on the timepiece side of the present invention.

[Explanation of symbols]

 1 Watch side 1a Back cover part 1b Groove part 2 Middle frame 2a Saray part 3 Eccentric screw 4 Hollow part of the body 5 Dial 20 Master 21 Mask

Claims (2)

[Claims] 1. The back cover is made of a noble metal such as a gold alloy or a platinum alloy having a thin thickness (35/100 mm or less),
A wristwatch side with a built-in reinforced middle frame, characterized in that the case and the back cover are integrated via a reinforced middle frame for supplementing strength. 2. The method for manufacturing a wristwatch according to claim 1, wherein a plating liquid made of a noble metal material is used to obtain an electroforming method by masking the inner surface of the back cover of the base material in advance. Is subjected to an inert treatment and plated to deposit a gold alloy with an average deposition thickness of 350μ or less, which is immersed in a strong acid to dissolve only the base metal, and the back cover is hollow only while the entire structure has a hollow structure. A method for manufacturing a wristwatch side with a reinforced inner frame in which a reinforced inner frame is closely adhered to the strength of the back cover part on one piece of a noble metal wall obtained by preventing it from becoming.