JPH0138573B2 - - Google Patents

Abstract

A method of making aluminium hands for timepieces comprises annealing an aluminium hand member 2 at 160-200 DEG C for 20-60 minutes, forcing the flange 3a of a (brass) bush 3 into the lower surface of a seat portion of the hand member, forming a protrusion 6 on the upper surface of the seat portion of the hand member, shaping the upper surface of the hand member by pressing, and finishing the the protrusion on the upper surface of the seat portion by machining using a diamond cutting tool. As illustrated the bush 3 is staked in the band member 2 by tools 4, 5 prior to annealing. A pressing step using dies 8, 9 forces the flange 3a into the member 2 and simultaneously forms the protrusion 6. After machining the hand is coated with gold. <IMAGE>

Description

[Detailed description of the invention]

The present invention relates to a method for producing an Al pointer. Recently, crystal watches have become increasingly smaller and thinner.
Furthermore, in order to extend the life of batteries, there is a strong demand for reducing the current consumption of modules as much as possible. In response to this demand, reducing the weight of analog clock hands is an important issue, and currently Al or Al
Alloy pointers are used. On the other hand, there is a strong demand for wristwatches these days to be high-quality products with beautiful exteriors and high-quality designs, and this has also become a major issue. In view of the above, the present invention provides a method for manufacturing Al pointers that are lightweight, have a rich design, and have a high quality appearance. In the manufacturing method of the present invention, a material with the same thickness as the pointer body is used, and the pointer body seat part has sufficient machining allowance for diamond cutting (hereinafter abbreviated as "diamond cut"), and other parts are used for the intended purpose. It is molded to the same thickness as the pointer body. The upper surface of the pointer seat is diamond-cut and processing allowance is required to achieve a beautiful finish.The other parts are made into a finished product by taking advantage of the embossed shape and quality. Obtaining a protrusion becomes important. Therefore, the present invention performs low-temperature annealing before stamping,
It was completed by using a method of stamping the molding process into the underside of the pointer seat. Next, the present invention will be explained in detail according to Examples. Figures 1 to 3 are drawings for explaining the process of the present invention, Figure 1 is a plan view for explaining the process of continuous press punching, and Figure 2 is a diagram for crimping the hakama on the Al pointer body. Cross-sectional diagram to explain the process,
FIG. 3 is a sectional view for explaining the embossing process. The material for the Al pointer was JIS A 5052R H18, thickness 0.10 mm, considering the strength of the pointer and press-cutting properties. The surface of the material is a mirror-rolled material with a beautiful finish. As shown in Fig. 1, an aluminum pointer body 1 (hereinafter abbreviated as pointer body 1) is cut out by a continuous press, and then, as shown in Fig. 2, a hole is formed for fixing it to the movement pointer shaft. A brass hakama 2 provided with this was fitted onto the pointer body 1 and fixed by caulking. In addition, in FIG. 2, 3 is a caulking punch. Next, the pointer body 1 was subjected to low-temperature annealing at a temperature of 180° C. for 40 minutes in order to restore elongation without reducing hardness. The hardness at this time was H _V 105 in the Al material part, and there was little deterioration in hardness from the initial hardness of the material, H _V 123, and the hardness and strength were sufficient as guidelines. still,
At a temperature of 160°C for 30 minutes, H _V was 114, and at a temperature of 200°C for 30 minutes, H _V was 98. 8% for elongation
~10%, and 2%, which is the initial rolling state of the material.
It has significantly recovered from 4%. Therefore 160℃~200
Good results were obtained by low-temperature annealing at ℃. Next, in order to add design to the surface of the pointer, the seat 6 of the pointer 1 was formed by a stamping process, and a curved surface such as a round instep was formed on the pointer 1. A slope 6a is formed on the seat. Since the surface quality of the pointer is important, the die for embossing is made of hard material.
The embossed surface was thoroughly polished until it became a mirror surface. The upper surface of the pointer body seat 6, which will undergo diamond cut processing in the post-process, which is an important point of the present invention, is cut with a shank 4 on the pointer seat 6 in order to obtain a sufficient machining allowance.
It was designed to be driven into the lower surface of the mold, and the amount of implantation 8 at this time was set to 20μ out of the 80μ thickness of Hakamatsuba 4, and embossing was performed. When the Hakamatsuba 4 was not driven into the lower surface of the pointer seat, it was difficult to stably obtain a protrusion amount of 30μ or more on the upper surface of the pointer seat, but the protrusion of the upper surface of the pointer seat obtained by the method described above Quantity 5 was 30μ or more, and the diamond cutting process in the next step could be stably produced with good quality and easily. In addition, in the conventional technology, in addition to requiring a press with a large capacity to obtain a thickness of 30μ or more, the pointer body 1 is subjected to a large force, causing deformation and expansion of the width of the pointer body, resulting in poor design and appearance quality. Therefore, it was not possible to complete a satisfactory Al guideline. If the low-temperature annealing process is not performed, a protrusion of more than 30 μm will not be obtained, and the sloped portion 6a on the upper surface of the pointer seat 6 will be subjected to excessive machining, resulting in wrinkles and cracks, resulting in the product being damaged. It didn't happen. If the temperature of low-temperature annealing is less than 160℃, the annealing effect will be weak and wrinkles and cracks will not be completely prevented, and if it exceeds 200℃, the strength of the pointer will deteriorate, which is undesirable from the point of view of functional quality. Therefore, in the present invention, the temperature of low-temperature annealing was set to 160°C to 200°C, and the time was set to 20 minutes to 60 minutes, also from the viewpoint of productivity. Next, the protrusion 7 on the upper surface of the pointer body seat was diamond-cut to give it a beautiful finish. After that, the pointer was thoroughly cleaned for the purpose of adding additional surface decoration.
A sputtering process was applied to the finished product, which was coated with an Au film and finished in gold. The Al pointer obtained by the present invention is lightweight,
The hooked part also has a very beautiful diamond-cut surface, and the result is an excellent Al pointer with a rich design that has a sloped seat and a round-shaped pointer body. The appearance quality of the embossed surface was beautifully finished by using a mirror-rolled material and the polishing of the embossed die, and was no inferior to the quality of the diamond-cut surface. Table 1 shows a comparison between the embodiment of the present invention and the conventional example. Conventional examples ○A is a model with a sharp collar driven into the pointer without annealing, ○B is annealed but the sharp collar is not driven into the pointer, ○C is annealed and the collar is driven into the pointer. It's something you don't do.

[Table] In the embodiment of the present invention, the Al pointer body and the hakama are fitted,
After crimping and fixing, low-temperature annealing and embossing were performed, but there is a method of low-temperature annealing of the Al pointer body before fixing the hakama to the pointer body, and then shank and embossing, or a method of hakama-kaji fixing and embossing at the same time. The same results as in this example can be obtained also in the processing method. Furthermore, it goes without saying that the shape of the pointer body can be processed into a rectangular shape, a chevron shape, a trapezoid shape, etc. in addition to the round shape described in the embodiment. As described above, the present invention provides a high quality Al pointer that is lightweight and has a high design quality.

[Brief explanation of drawings]

Figures 1 to 3 are drawings for explaining the process of the present invention. Figure 1 is a plan view for explaining the continuous press punching of the Al pointer body, and Figure 2 is a plan view for explaining the continuous press punching of the Al pointer body. 3 is a sectional view for explaining the embossing process, and FIGS. 4 and 5 are a plan view and a sectional view of the Al pointer according to the present invention. DESCRIPTION OF SYMBOLS 1... Al pointer body, 2... Hakama, 3... Caulking punch, 4... Hakamatsuba, 5... Protrusion amount, 6... Seat part, 7
...Protruding portion, 8...Dumping amount.

Claims (1)

[Claims] 1 In a method for manufacturing an Al pointer consisting of an Al pointer and a hakama, the Al pointer is heated to a temperature of 160°C to 200°C.
℃, low temperature annealing for 20 to 60 minutes, and the collar of the hakama is driven into the lower surface of the seat of the Al pointer body,
Forming a protrusion having a slope on the upper surface of the seat of the Al pointer, molding the upper surface of the Al pointer by embossing, and cutting the protrusion on the upper surface of the seat with a diamond. Al characterized by
How to make guidelines.