JPS6246161B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for joining a watch case and a wristwatch band.

Recently, there has been a trend for wristwatch cases, bands, etc. to become thinner and more irregularly shaped as more emphasis is placed on the decorativeness of watches. Therefore, there is a strong demand for a watch case that integrates a watch case and a band.

However, although attempts have been made to manufacture the case and band from the same material and are commercially available, it is technically extremely difficult and the manufacturing process is complicated, resulting in high costs, and the watch itself is also difficult to manufacture. Due to its natural limitations, it is expensive.

Therefore, research and development have been conducted on joining methods for joining and integrating separate components such as a watch case and a band. In other words, when joining a stainless steel square case and a stainless steel mesh band,
The joint surfaces are ground in advance and temporarily fixed by spot welding, and then a Ni-based alloy solder such as BNi-2 is used as the soldering material to join.
Ni-based alloy wax is brittle and has poor workability, so it is generally used in powder form, so in actual use, liquid is added to make it into a mud-like form, and then the joint surface of the case and band and its surroundings are painted with a brush. After coating with a method such as the following, the Ni solder was melted and bonded using an ammonia decomposition gas furnace or a vacuum furnace at 1150°C.
After that, the joint surfaces were polished and integrated. However, as mentioned above, when using conventional brazing material, the mud-like brazing material is applied, which causes the brazing material to spread over a wide area of the band, such as the space in the mesh band, resulting in loss of flexibility, etc. This resulted in broken pieces and impaired its decorative effect.

Furthermore, even when the end face of the band is ground before joining, since the Ni brazing material is brittle, each piece of the mesh band falls off, causing a defect called the eye drop phenomenon, resulting in a problem of poor yield.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to provide a joining method for integrating a watch case and a mesh-like band by brazing.

For the above purpose, in the present invention, two types of brazing materials having different melting points are used to perform brazing joining. That is, a first brazing material is placed at the tip of a mesh-like band, and the first brazing material is melted in a furnace to impregnate the band's tip with the first brazing material. Thereafter, the tip of the band is ground to integrate the band and watch case at a predetermined angle. After that, a second brazing material with a lower melting point than the first brazing material is placed at the joint between the tip of the band and the watch case, and only the second brazing material is melted in a furnace, thereby bonding the watch case and the mesh-like band together. Integrate by soldering.

Hereinafter, the configuration of the present invention will be explained based on examples.

The drawings show one embodiment of the present invention; FIG. 1 is a perspective view showing the end of a band, and FIG. 2 is a main part showing a joint between a watch case and a band manufactured by the joining method of the present invention. It is an enlarged perspective view.

A stainless steel mesh band 2 is manufactured by pre-processing a stainless steel rectangular watch case 1 into a predetermined shape by press processing, surface grinding, and a surface condition and shape that functions as a barrel polishing band, and is joined to the watch case. After adhering the brazing material flow preventive agent 4 to a region where the brazing material adheres with a gap d of approximately 7 to 8 mm from the end side 2a of the band, the first brazing material 3 is heated to a melting point of 1150°C. of
Au-Ni-Cu-Pd alloy plate (1.8mm x 20mm x 0.15
mm) of brazing material is placed at the end of the band in the gap of 7 to 8 mm, and placed in an ammonia decomposition continuous annealing furnace at 1150°C to fix the end of the mesh band and the mesh of the band.

After that, the watch case 1 and the band should have a joining angle of about 30°, which is suitable for joining for a decorative effect, and the first brazing material part 3 should remain in a width of about 2 mm. After grinding the band tip 2a and removing the first brazing material 3 from the band surface, the watch case 1 is polished (satainer processing) including processing of the band surface 5.
After making contact with the band 2, they are temporarily fixed by spot welding, and then a wire (0.2 mmφ x 20 mm) made of an Au-Ni alloy with a melting point of about 1000°C is soldered to the watch case as the second brazing material 6. After placing it on the back side of the joint between 1 and the band, it is finally fixed at about 1000°C in a continuous ammonia decomposition furnace with zero reducing atmosphere to form a completed exterior part.

According to this, the first brazing material itself, which has a melting point of 1150° C., serves as a flow preventive agent for the second brazing material, and the flow preventive agent is not needed at this point.

As described above, according to the bonding method of the present invention, the case and band are bonded to such an extent that the flow phenomenon of the brazing material is hardly observed with the naked eye, compared to the conventional method. This is due to the use of two or more types of brazing fillers with different melting points, as well as the use of solid plate-shaped or wire brazing fillers rather than liquids, making it suitable for exterior parts where decorativeness is important. The present invention provides a watch in which the case and band are more integrated.
Workability has been greatly improved by using plate-shaped or wire-shaped brazing material. In addition, a substance with a low melting point is
It is obvious that when used as a brazing material, the brazing material will be diffused over a wide range.

In the embodiments of the present invention, the stainless steel case and the band were joined together, but other parts can also be joined by step brazing by selecting an appropriate brazing material in consideration of wettability with the constituent parts and corrosion resistance. Exterior parts having decorative effects similar to those of the embodiments are provided and have great industrial value.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a perspective view showing the end of a watch band, and FIG. 2 is an enlarged perspective view of the main part of the joint between the watch case and the band. 1... Watch case, 2... Band, 3... First brazing material, 6... Second brazing material.

Claims (1)

[Claims] 1. In a method for joining a watch case and a band, in which a watch case made of a metal material and a mesh-shaped band are integrated by brazing using a brazing material, a first brazing material is placed at the tip of the band. The first brazing material is melted in a furnace to impregnate the space between the meshes at the tip of the band, and then the band and the watch case are integrally joined at a predetermined angle. For this reason, the tip of the band is ground, and then a second brazing filler metal with a melting point lower than that of the first brazing filler metal is placed at the joint between the tip of the band and the watch case and placed in a furnace. a step of brazing the watch case and the band by melting only the second brazing material; A method for joining a watch case and a band, characterized in that the second brazing material is prevented from diffusing into the space between the meshes of the band by acting as a brazing material flow prevention agent.