JPH0124873B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] This invention relates to an electroforming mold and a method for manufacturing the same.

"Conventional equipment and its problems" Conventionally, when producing an electroforming mold from a mother mold with concave portions on its surface, if electrodeposition is performed at a normal current density,
As shown in FIG. 2, the electrodeposited layer is formed thick locally, particularly in the convex portions 2, and therefore growth of the electrodeposited layer in the concave portions 3 is inhibited. Therefore, the current density in the electroforming process is set lower than the usual current density, but on the other hand, it has the disadvantage that it takes many days to form the electrodeposited layer. Furthermore, even if the current density is lowered, it is unavoidable that the electrodeposited layer on the uneven parts 2 and 3 will be non-uniform, and for this reason, it is necessary to perform machining after the electroforming process, which requires a lot of time and effort. shall be.

In addition, for the purpose of correcting non-uniformity of the electrodeposition layer, an auxiliary electrode 8 is used as shown in Fig. 3. Since electrodeposition is carried out by rotating the electrode, there is a disadvantage that a lot of time is spent on the preparation of the auxiliary electrode and the attachment device.

"Purpose" The purpose of the present invention is to perform electrodeposition at high speed even in the recesses where the formation of the electrodeposition layer is slow, in the production of electroforming molds having complex uneven parts such as tooth patterns.

"Embodiment" An embodiment of the present invention will be described below with reference to the drawings.

In other words, in FIG. 1, an electroforming master mold 1 is used for, for example, a tooth mold of a gear, and has a plurality of convex portions 2 and concave portions 3 formed on its surface. First, an electrodeposited thin film layer 4 with a thickness of 0.2 to 1 mm is formed on the surface of the matrix 1, and the thickness varies depending on the shape or size of the matrix 1. When forming, if the matrix 1 has a shape that allows electroplating, electroplating is more efficient, but if it is difficult to electroplat If the process requires a relatively long time, it can be formed by electroless plating. Next, on the surface of the electrodeposited thin film layer 4, the recesses 3 are filled with amalgam 5, so that the surface of the matrix 1 is shaped almost uniformly. Here, the main ingredient of the amalgam 5 is composed of tin (Sn), copper (Cu), zinc (Zn), or an alloy thereof. Next, the amalgam 5 filled in the recess 3 is hardened, and the surface has a thickness of about 0.01 mm.
A plating layer 6 of about 0.1 mm is formed. Note that this plating layer is preferably formed by electroless plating. When this plating layer is formed, the surface of the mother mold 1 has no irregularities, so the surface is then processed by electrodeposition using a plating bath that can run a high current, such as a nickel sulfamate bath. An electrodeposition layer 7 is formed thereon. As a result, an electroformed mother mold with a uniform surface is completed.

"Effects" In this invention, as described above, the concavities of the matrix are filled with amalgam and an electrodeposition layer is applied to the surface of the amalgam, so that the electroforming time is significantly shortened. In particular, according to this invention,
The process time can be reduced to one-third to one-half of the conventional method. In addition, unlike conventional methods, there is no need to perform separate machining after electroforming, so the rotatability of electroforming equipment is improved, and the efficiency of electroforming is greatly improved by saving electricity costs and plating chemicals. There are advantages.

[Brief explanation of drawings]

FIG. 1 is a front sectional view showing an embodiment of the electroforming method according to the present invention, and FIGS. 2 and 3 are front sectional views showing a conventional processing method. 1... Matrix, 2... Convex portion, 3... Concave portion, 4...
Electrodeposited thin film layer, 5... Amalgam, 6... Plating layer, 7... Electrodeposition layer.

Claims (1)

[Scope of Claims] 1. An electrodeposited thin film layer is formed on the surface of a matrix having uneven parts, and on the surface of this electrodeposited thin film layer, the recesses are filled with amalgam, and the surface of this amalgam is activated. A method for producing an electroforming mold, further comprising applying an electrodeposition layer to the surface of the amalgam. 2. An electrodeposited thin film layer is formed on the surface of the matrix having irregularities, and on the surface of the electrodeposited thin film layer, a filler made of amalgam is filled in the recesses, and an electrodeposited layer is formed on the surface of the filler. An electroforming mold characterized by applying.