JPS5825741B2 - Manufacturing method for exterior parts for watches - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing an exterior part for a watch, and it is an object of the present invention to provide a method for producing a thin watch side through a simple process at low cost and with a free design.

Traditionally, thin-walled watches have been manufactured in such a way that they are manufactured into a predetermined shape through various processes such as drawing and press processing, and then by cutting, etc., or they are formed using a casting method such as lost wax, and then processed by cutting, etc. There were methods of manufacturing it into a predetermined shape.

However, the above manufacturing methods have various drawbacks.

Regarding drawing processing, there are restrictions on plate thickness, shape, and design due to processing issues.

Particularly in terms of plate thickness constraints, it is extremely difficult to draw ultra-thin plates, which is a major bottleneck in dealing with the trend towards thinner plates.

Furthermore, since the plate thickness could not be made thinner, the amount of material used for the watch side increased, resulting in a significant cost increase for watch bodies, especially products that used precious metals.

Furthermore, as watches become more fashionable, if diversification of designs becomes a priority, not only will the number of drawing processes increase, but the process itself will become impossible.

Like drawing, press working also has restrictions on plate thickness, shape, and design due to processing problems.

Furthermore, it took a large amount of man-hours to remove the particles generated during the press process, which led to an increase in material costs.

Compared to drawing and press working, the casting method has fewer restrictions on shape and requires less raw material for the watch.

For this reason, it is most suitable for manufacturing precious metal watches, but on the other hand, casting has the disadvantage of generating cavities, so it is still difficult to apply it to watches where appearance quality is important. Defects (particularly in hot water running) have occurred and remain a problem.

As explained above, with the current manufacturing method, there are many constraints on shape, plate thickness, and design as well as factors that increase costs when manufacturing thin-walled watch sides, making it extremely difficult to expand mass production.

Therefore, the purpose of the present invention is to solve the above-mentioned drawbacks by combining casting, especially die-casting, and surface treatment technology, so that thin-walled watch parts can be manufactured at low cost without being subject to restrictions on plate thickness or shape. It is intended to be easily manufactured.

The gist of the present invention will be explained below with reference to the drawings.

In FIG. 1, reference numeral 1 denotes a male mold for an exterior part for a watch made of chemically soluble metal molded by die-casting.

Materials for the male mold 1 include die-castable Zn (zinc), A7 (aluminum), Sn (tin), Cu (copper), Mg (magnesium), Fe (iron), brass, nickel silver, stainless steel, etc. Examples include metal materials such as steel.

In addition, since a metal layer will be formed on the outer peripheral surface of the male mold 1 in the next step,
The metal layer 2 is manufactured in advance with predetermined dimensions with a reduced thickness.

Next, as shown in FIG. 2, surface treatment such as wet or electroless plating, vapor deposition, or sputtering is applied to the male mold 1 of the watch exterior part, and a metal layer 2 is deposited until it reaches the dimensions of the watch side, thereby forming the finished watch side part. Manufacture.

The material of the metal layer 2 includes Ni, Pd (lead),
・Au (gold) -AJ' (silver) -Rh (rhodium)・
Examples include Ru (ruthenium) or alloys thereof, and multilayer coatings of the above materials.

The thickness is set to 50μ to 500μ.

This is 50μ, considering the watch side currently in use.
If it is less than 500 μm, it will not be strong enough to be used as a watch and the movement will be damaged, and if it is more than 500 μm, it can be sufficiently manufactured by drawing, and there will be no cost advantage.

As shown in FIG. 3, a machined hole 3 is provided on the inner surface of the completed watch side manufactured by the method described above so that the mold release 1 can be chemically dissolved.

Next, the male mold 1 is selectively chemically dissolved in the outer peripheral metal layer 2 of the completed watch side part to produce the female mold 4 of the watch exterior part.

This female mold 4 is subjected to simple cutting and polishing and used as a watch side.

Since the watch side according to the present invention is a combination of die-casting and surface treatment technology, the die-casting method has excellent dimensional accuracy, especially when using Zn Guicasting, product dimensions can be reduced to 5~5~
It is possible to press with a tolerance of 71n7IL.

Then, the constraints on shape expanded widely, and as long as a mold was made,
You can create almost any shape.

Furthermore, by using surface treatment technology, the thickness of the plating layer, that is, the thickness of the watch side, can be adjusted to match the material strength and the strength of the watch side, making it possible to obtain extremely high quality watch sides.

Furthermore, problems with plate thickness, shape, design, processing, etc., which were shortcomings of conventional manufacturing methods, can be resolved, making it possible to significantly reduce costs in terms of manufacturing man-hours and materials. was extremely effective.

The following will be explained based on examples. Example 1 A male watch mold 1 is cast as shown in FIG. 1 using the Zn cast method.

JIS ZDC-2 is used as the zinc material.

This cast product has an average of 20
The molding was performed by adjusting the plating thickness of 0μ.

Next, apply the Au to Ag alloy plating solution (Aurobase UG-16, manufactured by Nichijo Seiko Co., Ltd.) to the main cast zinc side as shown in 2 in Figure 2.
The cast zinc side was plated to a thickness of about 200μ using a metal plate to finish the finished product dimensions.

After this, three zinc elution holes (corresponding to 3 in Fig. 3) are made on the inner surface of the watch side (the part that does not appear externally).

This watch side is immersed in a dilute nitric acid solution of HNO3:H20=1=1 to chemically dissolve the zinc material.

The zinc material could be completely dissolved in about 36 hours by simple immersion at room temperature.

After performing simple cutting and polishing on the watch side of the 18 thus produced, approximately 5 μm of finishing Au plating was applied to complete the watch side of the gold 18.

Example 2゜ A watch side was manufactured by casting using the Zn Gui casting method.

This cast product has an average of 22 mm in each dimension in consideration of the surface treatment in the next process
The plating thickness was adjusted to 4μ.

Next, add Cu200μ-N i 20μ-P to the main cast zinc side.
224μ plating was applied to the d4μ configuration, and the cast zinc side was finished to the finished product dimensions.

After that, it was immersed in dilute hydrochloric acid (HCl:H20=1:1),
The watch side was manufactured by chemically dissolving zinc material.

This watch side was subjected to simple cutting and polishing, and then Rh plating of 0.5 μm was applied as a finishing plating to complete the watch side.

In addition, the exterior parts for a watch of the present invention include the side body, back cover,
In addition to the glass rim, this includes the crown, buttons, dial, parting board, band, etc.

As explained above, the present invention is an extremely effective manufacturing method, and can be widely applied not only to watches but also to ornaments.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a cross-sectional view of an exterior part for a watch molded by die-casting. FIG. 2 shows a partial cross-sectional view of a timepiece exterior part subjected to surface treatment. FIG. 3 shows a state in which holes have been made in the surface treatment layer and the exterior parts for the internal watch have been dissolved and removed. DESCRIPTION OF SYMBOLS 1...Male mold for an exterior part for a watch, 2...Metal layer, 3...Melting hole, 4...Female mold for an exterior part for a watch.

Claims (1)

[Claims] 1 Exterior parts for watches made of chemically soluble metal molded using a casting method, with a thickness of 50μ to 500μ on the outer surface of the male mold.
1. A method for manufacturing a watch exterior part, which comprises forming a metal layer, and then chemically dissolving the male die selectively with respect to the outer metal layer to make the outer metal layer into a watch exterior part.