JPS58219476A - Case for wrist watch - Google Patents

Abstract

PURPOSE:To simplify and speed up the production process of a wrist watch case with a novel and excellent design by irradiating the surface thereof with a laser beam to cause a thermal stress on the surface layer of the case. CONSTITUTION:A laser beam irradiates the surface of a case 21 for a wrist watch made partially or wholy employing non-metal material such as opaque glass, sapphire, agate, crystal containing impurities and tigereye to heat it rapidly. This generates a fine crack 22 or an internal heat stress on the surface layer which cause light to be reflected and scattered at affected points to create a pattern.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to surface patterning of cases used in wristwatches.

The present invention relates to a novel method for patterning the surface of a wristwatch case using laser light.

When mechanical wristwatches were at their peak, consumers focused on the time accuracy of the watch body, and the appearance of the wristwatch did not hold much weight. However, as quartz wristwatches using crystal oscillators have become widespread, wristwatches with sufficient time accuracy that are used as accessories in daily life have become commonplace.
Consumers' criteria for choosing a wristwatch has changed to whether the design is time accurate or not. Therefore, the appearance, texture, luxury, and precision of a case that is evaluated as a wristwatch have become most important in manufacturing a wristwatch case.

A typical method for manufacturing a wristwatch case by the conventional method is shown in Fig. 1 schematic process diagrams (A) to (C). First, a case raw material 2 is formed from a cap board 1 using a Luss mold. The raw material punching process (a), secondly the forging process (b) in which the outer shape part and the surface coining pattern 6 are formed from the case raw material 2 using a press forging die, and the sixth is the forging finished case 4. The case 4 is further subjected to a machining step (c) in which the inner portion 5 is processed using a lathe or the like, and the outer portion and the surface coined pattern 3 are mainly subjected to puff polishing.
Complete the watch case by plating as necessary.

In addition, when making a watch case using the above method, the forging process (b) is the main step in creating the design, and naturally the forging mold is engraved with various patterns such as engraved patterns and wave patterns. It goes without saying that a well-prepared mold must be used. Furthermore, for patterns that are difficult to process in the forging process (b), after the machining process (c) is completed, fine designs are applied using Nando paper, hand files, engraving tools, etc.

Other conventional methods include metal rods or metal plates.
The No-milling method uses a milling cutter to finish everything from the raw material extraction step (a) to the machining step (c) shown in Figure 1 in one step. Still another method is the injection molding method, in which a glass material is injection molded and the finished product can be obtained immediately after one surface treatment. Still other methods include a casting method (IcI Stwax method) in which molten metal is poured into a simple mold to form the outer shape of a wristwatch case in one step. However, manufacturing wristwatch cases using these methods has various problems, particularly those that do not comply with today's manufacturing methods and market conditions: (1) Design (outside shape) is restricted by the mold; ,
As a result of not being able to fully reflect the designer's intentions in the product,
We can only create watch cases that never change.

(2) Dedicated mold (mold) 1r for each design: Because it is required, it takes time to manufacture the mold (the master who makes the mold) and the delivery date becomes longer.

(3) Due to (2) above, the production cost of the mold (the mold or the master who makes the mold) is high, so it is difficult to depreciate it unless it is a model produced in Europe.

+411JC In cases where long processing is required using an expensive machine such as a milling machine (such as when creating a fine surface pattern), the machine depreciation cost per product is very high and the practicality is poor.

(5) Since the shaping and patterning of a watch case cannot be considered separately, approximately 80% to 90q6 is required for the design when molding the external shape.
I need to finish my work. Therefore, since it is necessary to manufacture each model from a process close to the raw material process, we use the F'MS production method (preparing a watch case with a general shape and finishing it with a specified design in a process close to the final process). is difficult to hire. I rarely hit the top of my head.

The present invention has solved all of these drawbacks, and its purpose is to make it possible to manufacture a watch case with an excellent novel design, and to simplify and speed up the manufacturing process of the watch case. It consists in plotting to change. The present invention will be described in detail below based on Examples.

Needless to say, laser light has already been put into practical use in other fields, and its features include the ability to provide high energy and easily narrow down the area of energy. With the addition of a microcomputer, etc., the IE can be accurately irradiated to any position by operating a reflector or table.

When designing the wristwatch case 6 shown in Figure 1 (creating a pattern on the case surface) using such laser light, the conventional method shown in Figure 1 is the raw material extraction process (( ), after completing the forging process (b) and machining process (c), which target only the part that becomes the skeleton of the external shape (excluding the coined pattern 3 on the surface), as shown in the laser processing diagram in Figure 2. A laser beam is scanned in the direction of the arrow from above the machined upward case 11 to sublimate, remove, and melt a portion of the material on the surface of the machined upward case 11 using the laser source energy. 6- It is possible to draw a surface pattern 12 in which other parts are relatively convex parts.It is possible to draw the surface pattern 12 in which the fine irregularities are scanned in a fixed pattern b times, and by controlling the energy needle and the spot diameter. In this way, when patterning is performed using laser light, the material to be irradiated with the laser beam is all stainless steel, the laser beam spot diameter is 20 am to 50 am, and the output is 20 am to 50 am. Cuff', (5~
50 W, pitch of spot If4+≦spot diameter,
This becomes possible by doing this. In this case, when the irradiated surface is at a right angle to the laser beam, the strongest pattern can be created. The laser beam irradiation position and range will be controlled by a microcomputer, but since the laser beam reflectance varies greatly depending on the surface condition of the irradiated material, the power should be lower for rough surfaces, and higher for closer surfaces. It is not possible to create a uniform pattern unless this is done. In addition, as a method to reduce the laser beam reflection from the surface of the irradiated material, a thin film that prevents (absorbs) the reflection of V-boo light is applied to the surface of the irradiated material, such as black N1 plating, thermal butcherization. Patterns can be easily created by irradiating laser light after applying coloring or black coating, and then removing the thin film.

Another method is to use non-metallic materials such as opaque glass, sapphire, agate, crystal containing impurities, and gemstone as the material for the watch case 21, as shown in Figure 3. A laser beam is irradiated onto the surface used for part or all of the case 21 to intensely heat the entire surface of the wrist watch turf 21, causing minute cracks in the edge surface layer or internal thermal stress in the rack 22, and crack 2
2. Alternatively, light refraction and light scattering can be caused in the area where internal thermal stress occurs, and this can be used as a pattern.

Naturally, the output of the laser beam, irradiation time, spot diameter, and irradiation interval vary depending on the material to be processed, the surface condition, and the required appearance, but in general, the output is 5 to 50 W, and the output is 0.01 W.
~0.55ec irradiation, 20-60μm spot diameter V
(Eng.) It can be made possible.

Another method in history is to coat the surface of the wristwatch case 51 with an organic thin film layer, as shown in FIG. 4, a cross-sectional view of the wristwatch case.
After providing the surface thin film layer 52 consisting of a gold plated layer or the like,
The thin film layer 62 is sublimated or melted by irradiating a laser beam in the direction of the arrow and performing a rapid heating operation locally, thereby exposing the base of the wristwatch case 31 or changing the N film 1-32. By repeating such operations, it is possible to form the desired pattern on the surface of the gold watch case 51, and also to emboss a rainbow pattern on the surface of the watch case 31 in advance using a mechanical method or the like. This makes it possible to create designs with even more depth.

Still another method is to apply a plurality of thin film layers 42, 43 of different organic materials or metal plating on the surface of the wristwatch case 41, as shown in the cross-sectional view of the wristwatch case in FIG. The thin film layer 43 or 42.43 can be removed to form a pattern by irradiating the surface of the case 410 with a laser beam in the direction of the arrow. In this case, the intensity of the laser beam output is adjusted to control the outermost thin film layer 43 or a plurality of thin film layers 42.
45 or not. Therefore, if a number of thin film layers of different colors are provided, the relevant parts will be irradiated.
The surface can be patterned in multiple colors.

In contrast, by using laser light to pattern the surface of the watch case, compared to the conventional method, the pattern is formed using a collection of microscopic dots with a spot diameter of 10 μm to 50 μm. It has become possible to create innovative designs that are outside the box.

■ Since any pattern can be easily and quickly applied to any part of the surface of the watch case, the period from deciding on the design to completing the product is extremely short, which is less than 1% compared to conventional methods.
'The time required for actual processing was at least half a day.

■ Since special jigs, tools, and auxiliary tools are not required for each design, it is possible to save costs, and as a result, the cost of watch cases can be reduced. Especially the same-
Specifications It is particularly effective in reducing costs when the number of watch cases is small, and the cost is 30% to 50% lower than that of conventional methods.
It can be manufactured in 0.

■ Because the method instantaneously heats a minute area, there is virtually no thermal effect on the entire watch case, and warping, bending, twisting, etc. of the watch case caused by the heat generated by the laser light cannot be detected.

Therefore, there is almost no mechanical stress or thermal stress that would be a problem when applying mechanical processing using conventional methods, so the watch case can be strengthened due to the manufacturing method (increase in wall thickness of each part of the watch case). etc.) is no longer necessary, and a simple watch case can be realized.

■ Design changes can be made extremely easily by adjusting laser light output, speed, spot diameter, etc. These changes can be made in about 10 minutes, compared to 7' (2 to 3 hours) required in conventional machining, and are highly flexible.

As mentioned above, we have described patterning the surface of a watch case using laser light, but these methods can be applied to all shapes, regardless of whether the planar shape or cross-sectional shape is round, square, oval, or irregular. Needless to say.

The laser light suitable for the above method is YAG laser light with a wavelength of 1.06 μm.

Since the wavelength of YAG laser light is particularly transparent (not absorbed) by transparent glass, the optical system of the laser device is easy to handle, structure, and maintain. If a transparent glass layer is used as the thin film layer when patterning is performed by irradiating YAG laser light after the formation, the energy can be absorbed by other thin films without giving a shadow 111 to the layer. be able to. In this usage method, a transparent vitreous layer is provided as the outermost thin film layer, and when a YAG laser beam is irradiated to a place where the other thin film layers are made of laser light absorbing material (for example (+r plating layer, etc.)), the outermost thin film layer is There is no change in the transparent glass layer, but the laser light absorbing thin film layer that exists between the transparent glass layer and the watch case can be patterned, which adds novelty to the design and improves the watch case. It can be said that laser light has extremely useful properties that can also improve corrosion resistance.

Laser Mate 50, manufactured by Fuji Electric Manufacture -K, is a representative laser machine used for such purposes. It is a useful machine that can quickly irradiate any location on the body, has a simple device, and is economical in running costs, and can be used in a variety of ways in the future.

[Brief explanation of drawings]

Figure 1: General process diagram for conventional wristwatch cases, (a) raw material extraction process, (b) forging process, (c) machining process, 1
...Golden maple board, 2...Case raw material, 3...Surface coined pattern, 4...Forged top case, 5...Inner part, 6...Machine finished top case. Fig. 2: Conventional laser processing diagram; 11: Machined upward case; 12: Surface pattern - 15 uniform; Fig. 5: External view of the wristwatch case of the present invention; 21: Wristwatch case. , 22... Crack, FIG. 4, sectional view of the wristwatch case of the present invention, 31... Wristwatch case, 32... Thin film layer, FIG. 5, sectional view of the wristwatch case of the present invention, 41.・・Watch case, 42.43・・
・Thin film layer, above applicant: Suwa Seikodai Co., Ltd. Agent, Patent Attorney Tsutomu Mogami-14-

Claims (6)

[Claims] (1) A wristwatch case characterized in that the surface of the case is irradiated with laser light to provide regular irregularities on the surface of the case. (2) A wristwatch case, characterized in that the surface of the case is irradiated with laser light to cause thermal stress on the surface layer of the case. (3) A wristwatch case characterized in that a thin film layer is formed on the surface of the case in advance, and then the thin film layer portion is irradiated with laser light to melt or remove the thin film layer in the laser light irradiated portion. (4) After forming multiple thin film layers on the case surface in advance,
A wristwatch case characterized in that the thin film layer portion is irradiated with laser light to melt or remove one or more thin film layers in the laser light irradiated portion. (5) A wristwatch case according to claims 1 to 41J, characterized in that a pulsed laser beam is used. (6) Adjust the laser beam spot diameter to 10 μm to 50 μm.
Claims 1 to 5, all of which are characterized by m.
Case for the watch mentioned in section.