JPS625304B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing watch hands formed by applying electroforming technology.

Conventionally, hands have been generally used as time display members in analog display type watches, and materials such as copper alloys such as brass and phosphor bronze, and aluminum alloys are often used. In addition, the most common processing method is to use a needle with a thickness of 150μ to 200μ, in which the predetermined outline and holes are punched out using a press as shown in Figure 1, and then the hakama part is bent as shown in Figure 1. there was.

However, recently, consumers' demands for watches have increased.
There has been a strong trend toward thinner and more compact designs, and this has also had a strong influence on watch hands. For this reason, stronger and thinner watch hands are desired, and in addition, hour, minute,
It became necessary to reduce the spacing between the three types of hands that displayed seconds, or the spacing between the dial and the hands, to zero or extremely thin.

However, using conventional processing methods or materials, it has not been possible to satisfy these requirements.

The present invention solves these problems and has succeeded in producing an extremely thin and strong needle by integrally molding the needle and the hakama part of the needle by applying electroforming technology.

The details of the clock hands with hakama according to the present invention will be explained with reference to the drawings.A typical manufacturing method is 1-1 in Fig. 2.
There are a, 1-b, and 1-c. To explain Fig. 2, masking 3 is applied to the surface of the flat mother die 1 in a pattern that leaves the pointer body having the intended attachment hole 2a and needle outer shape 2b (Fig. 2-1).
-a), then several μ using any metal salt solution
The metal is deposited to a required thickness ranging from m to several tens of μm. Next, masking 3' is applied in a pattern that leaves the hakama part 2' only on the outer periphery of the attachment hole 2a of this electroformed layer (needle 2) (Fig. 2-1-b), and the desired hakama thickness is again applied. (Fig. 2-1-
c) After this, when this electroformed layer (hand 2) is peeled off from the matrix 1, a clock hand 2 with a hakama is obtained. In this method, the surface condition of the matrix directly appears as the surface condition of the needle, so it is more effective in processing needles with arbitrary patterns than mirror-finished needles.

In addition, in the method shown in Fig. 2, the electrodeposition of the pointer body (see b) and the electrodeposition of the hook (see c) are separate processes, so the materials of the pointer body and the hook are made of different materials. I can do it. For example, if the pointer body is made of nickel and the hook is made of brass, the pointer body has great strength because the hook is made of brass, and although it is hard, it can be easily attached to the rotating shaft as before.

The method for manufacturing electroformed needles according to the present invention has been described above, but to explain the electroforming process in more detail, first, the material of the master mold used in the first step is a durable master mold (aluminum, stainless steel, brass, etc.). , glass, nickel, etc.) and consumable molds (low-melting alloys, plastics, wax, plaster, viscosity, etc.), and it is possible to manufacture using either of them, but in order to do it more precisely and economically. Brass, which is a durable matrix, is suitable for this.

In the second step, the matrix material is machined or chemically treated such as etching to form the desired shape, and then paint, lacquer, wax, etc. is applied or immersed, or oxides and sulfides are chemically treated. Forms a coating and makes it easier to peel off the electrodeposited metal from the matrix.

Next, regarding the electroforming bath used in the third stage of electrodeposition work, it can be used for various types of copper, nickel, and iron electroforming, and for high-end products, it can be used alone or in combination with various noble metal electroforming baths. However, nickel electroforming is generally effective in terms of strength, cost, etc.

Next, the features of the present invention are listed: (1) Needles with a wide range of physical properties can be easily obtained by changing electrolytic conditions, bath composition, additives, etc. For example, those using nickel electroforming have a hardness of HV 500 to 650, and are strong enough to withstand use even with a thickness of about 5 to 40 μm, and are about 1/40th of the thickness of conventional needles of 150 to 200 μm. You can get extremely thin needles. This ensures that the gap between the needles is 0.
Or, even if the hands touch each other by a very small amount of a few microns, the torque is the same as before, and there is no effect on the movement of the hands.
Drive smoothly.

(2) Since the surface condition can be accurately reproduced, needles with high decorative effects can be obtained according to the designer's wishes.

(3) Due to the high dimensional accuracy, there is no problem fitting the hour wheel or each axle even if the clock hands with hakama are integrally molded.

(4) Since it does not require large-scale equipment, it is suitable for producing a wide variety of products in small quantities, such as watches.

(5) As long as it is used for watch hands, it is possible to easily obtain hands that fit the watch without any restrictions on size or shape.

(6) By molding the pointer body and the hakama part from different metals, the strength of the pointer body can be increased and hardened, and the hakama part can be made soft, making it easy to attach to the rotating shaft and creating a watch that is strong despite being thin. This has a great effect on making the needle thinner and smaller.

The typical manufacturing method, features, and effects of the present invention have been described above, but as long as the needle is processed by applying electroforming technology, regardless of the manufacturing method or how it is used,
None of these depart from the purpose of the present invention.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view showing an example of a conventional method for manufacturing a watch hand, and Fig. 2 is a cross-sectional view showing a typical method for manufacturing a watch hand according to the present invention.
1-b and 1-c indicate each step. 1... Matrix, 2... Needle, 2'... Hakama part, 3...
Primary masking, 3'...secondary masking.

Claims (1)

[Claims] 1. In a method for manufacturing watch hands using electroforming technology, there is a step of masking the surface of a flat matrix in a pattern that leaves a pointer body with the desired mounting hole and the outer shape of the needle; a step of forming an electroformed metal layer on the surface of the mother mold; a step of masking the electroformed metal layer in a pattern such that a hakama portion is left only on the outer periphery of the attachment hole;
A watch comprising the step of forming an electroformed layer of a metal different from the metal of the pointer body on the hakama portion, the metal electroformed layer with the hakama being peeled off from the mother mold and molded. How to make needles.