JPS6017038B2 - Mold electroforming method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The disclosed technology belongs to the technology of coating a matrix with an electromagnetic body in the haze forming of mold electrodes used in electrical machining such as electric discharge machining and electrolytic machining.

Therefore, the present invention uses electricity in the process of rusting an electrified coin mother mold that is made of a conductive material in a dew coin liquid or has at least a surface portion that is to be made conductive. Since it is difficult to conduct coins, we aim to averagely disperse or concentrate the dew coin current by applying a magnetic field to the uneven points, and to ensure that the uneven points are covered with electromagnetic mirrors. The present invention relates to a method for making money using a mother mold, and in particular, during molding of the mother mold, a magnetic force generating body such as a permanent magnet or an electromagnet is buried in advance in the mother mold of the pointed uneven portion by embedding it in rust. is carried out, and when the dew coin is used, the electromagnetic current in the dew coin liquid is attempted to be dispersed or concentrated by the magnetic force of the magnetic force generating body,
The present invention relates to a matrix electromagnetic mirror method that allows the coin body to be coated more uniformly and with the same thickness over the entire surface.

As is well known, many of the machining electrodes of the full-form machining type used in electrolytic machining, electrical discharge machining, etc. have a crab-shaped surface treated on the machining surface or are reinforced with a haze mirror shell on the backing. It is used.

As shown in FIG. 1, the machining electrode has the machining surface 2 of the machining mold body 1 made of the backing reinforcing material etc. coated with the haze rust body 3 in a predetermined manner. In addition to a simple flat surface or a gently curved surface, the surface 2 often has at least one locally pointed uneven portions 4, 4. The degree to which ... is involved in processing has a deep relationship with processing accuracy and quality of the final product.

Therefore, it is extremely important to ensure that the sharply uneven portions 4, 4, etc. of the coin body 3 have a uniform thickness with respect to the other surface, including durability.

By the way, as shown in FIG. 2, regarding the molding of the coin body 3, for example, a male mold (not shown) is used to mold the cavity part of the mother die 5 with resin such as silicone resin to the outer surface of the predetermined coin body 3. If the resin of the mother mold 5 does not have a certain electrical conductivity due to the addition and mixing of conductive powder such as metal, it may be molded on the same processing surface 2', by appropriate well-known means such as chemical plating. The conductive treatment layer 6 is formed by forming the conductive layer 6, and the kasumi body 3 is formed by coating the kasumi body 3, and then the kasumi body 3 is peeled off from the matrix and filled with a backing reinforcing material, or It was supposed to be glued etc.

However, in the conventional dew coins in the dew coin liquid, the dew coin current has very little or no current density in the pointed uneven portion 4, and as shown in FIG. had the disadvantage that the coverage was almost equal to zero.

In this case, the other electrode for the conductive layer 6 is connected to the layer 6.
If the mirror body 3 can be placed at an infinite distance from Exposure is performed by reducing the density, but it goes without saying that uniform exposure cannot be achieved, and on the other hand, it takes a very long time. Because it requires about 0.7 side due to wear and strength, the time required for the above-mentioned electric key is longer than expected, and it also requires rework such as manually scraping off the coin needle crystal etc. in the middle of the electric mirror. is required over and over again.

For this reason, auxiliary electrodes in the form of rods, needles, etc. are placed close to the pointed uneven parts 4, 4', which are the weak points of the coin where the electrolytic rust layer is not formed. However, the reality is that Kamesen still cannot be used in a satisfactory manner.

In contrast, for example, the inventor's earlier application,
As seen in Publication No. 0-85, a method has been developed in which the magnetic flux is varied in a liquid in the recessed part of the workpiece, the current density is controlled, and a uniform coating of the lightning body is obtained. .

However, since this type of method changes the magnetic flux from the outside of the workpiece (matrix), it may be applicable if the workpiece has a large concave part or a small curvature, but it may be applicable if the concave part of the workpiece is large or the curvature is small. If there are multiple units and they are close to each other, it is difficult to apply different controls to each unit under different conditions.

In addition, since the magnetic flux imparting body is located outside the workpiece, there is a problem that the magnetic flux cannot be directly involved, especially locally concentrated, due to the distance from the peaked unevenness. A shielding means against the liquid is also required, the device structure is complicated, operation management is difficult, and manufacturing costs are high. The purpose of the present invention is to solve the above-mentioned problems of the conventional mother mold bell method, and to solve the problem, when forming a mother mold, a permanent magnet or , by burying an electromagnet in a metal container, etc., applying a conductive treatment to the covered surface of the haze mirror body 3 as necessary, immersing it in the haze liquid, and performing a filtration process, the mirror current can be eliminated. The magnetic flux is controlled by the magnetic flux, concentrates on the pointed uneven portion, and disperses, resulting in a more uniform covering of all the coin body, and even on the pointed uneven portion, etc., it is more uniform than other parts. It is an object of the present invention to provide an excellent method for making a mother-shaped coin that can be made to have a certain thickness.
Next, one embodiment of the present invention that achieves the above object will be described below with reference to the drawings from FIG. 4 onwards.

It should be noted that the same parts will be explained using the same reference numerals. As shown in FIG. 4, a mother mold 5 having the same machined surface 2 as a mold for electrolytic machining or electric discharge machining is molded using silicone resin using a mold (not shown).

In the molding process, a rod-shaped mold, a short cylindrical mold, Permanent magnets 7, 7, etc., which have a predetermined shape and size such as a bowl shape, and which can cause lines of magnetic force of a predetermined density to act on the predetermined shape and size, are appropriately set in a mold and integrated with silicone resin, etc. Shape by casting into.

When the mother die 5 is molded, a conductive layer 6 is lined over the entire surface of the molded surface 2 by a predetermined method such as chemical plating.

This layer 6 is not necessary if the resin forming the matrix 5 is made conductive as described above.

As shown in FIG. 5, the mother mold 5 that has been pretreated in this way is housed with a lead wire 9 connected to it in the dew layer 8, and is connected to a power source 10 as a cathode, while a predetermined anode 11 is connected to a lead wire 9 as a cathode. By connecting to the power supply 10 via the line 12, placing both the counter poles 6 and 11 facing each other in a predetermined charge liquid 13, and turning on the switch 14, a coin charge is started. In the dew-hoko process, the electromagnetic current flowing from the anode 11 to the cathode 6 passes through short-passed adjacent areas, flat areas, etc. as usual, and then flows toward the pointed recesses 4, 4, etc. However, in this invention, the magnets 7, 7, etc. as magnetic force generators are buried in the matrix 5 of the pointed recesses 4, 4, close to each other. According to Fleming's law, the crab rust current is prevented from local concentration and is dispersed, and
..., and as a result, the electric mirror body 3 is concentrated on the entire machined surface 2.
is coated with an average and uniform thickness as shown in FIG. 6, and of course the pointed recesses 4, 4... are coated with an average thickness. As mentioned above, the design aspect of the permanent magnets 7, 7, . . . is, of course, determined theoretically and experimentally by optimum design. Therefore, when the pointed uneven portion in the present invention is roughly divided into a horizontal bowl-shaped recess (cusped recess) and an inverted basin-shaped projection (pointed convex portion), each uneven portion As for the shape or arrangement state and dimensions of the magnetic force generating body to be buried in accordance with
That is, the pointed convex part of the electrocorrosion matrix is aligned with the axis in the direction facing the anode, and a magnet with a diameter and length approximately proportional to the diameter and height of the pointed convex part (the magnetic pole of the magnet The direction may be any direction as long as it is in the above-mentioned axial direction.

), and on the other hand, as shown in Figures 4 to 6, the pointed recess has an annular structure surrounding the recess axis and extending in the direction of the bag. It is sufficient to bury a magnet that can act on a magnetic flux, and the inner diameter and length of the magnet in all axial directions are approximately proportional to the length and depth of the pointed recess. A plurality of bar-shaped magnets may be arranged in an annular shape. In addition, the above is a case where the electroformed mother mold and the anode are arranged facing each other at a distance from each other in the direction of the sea bream of the pointed unevenness of the mother mold, as shown in FIG. In this case, the conductive layer is preferably not made of ferromagnetic material and does not form a magnetic conduction path larger than a predetermined length. Furthermore, for the pointed convex portion, if bar-shaped magnets are arranged and buried near the base of the convex portion in a radial manner, for example, in a square shape, the effect is almost the same as that described above; The aforementioned magnetic force generating body for the square recess is a rod-shaped body whose anode has an outer diameter that is sufficiently larger than the diameter of the recess, and this rod-shaped anode is coaxially inserted into the pointed recess from the entrance side. It was almost equally effective when electroforming was carried out.

The mother mold 5 exposed in this manner is taken out from the exposure tank 8, a predetermined release material is injected, the haze body 3 is removed, and the first
As shown in the figure, attachments are appropriately attached to the processing die main body 1.

According to an experiment as shown in FIG. 7, the central angle of the pointed recess 4 was 600, the slope length (vertical length) of the recess was 14,
If the lining thickness of the key body 3 at the upper and lower ends 1 side is h,, h2 as shown in the figure, when the key is pressed with a current of 1 boat/d, the data of h2/h, x 100 is As shown in the table below, it was found to be extremely effective.

Note that the permanent magnet was a Fe-Cr-Co-Ti alloy, and the same was true when permalloy was used.

It goes without saying that the embodiments of the present invention are not limited to the above embodiments; for example, instead of a permanent magnet, an electromagnet with an excitation coil wound around a magnetic core of a predetermined shape, or an air-core excitation coil may be used. There are various aspects such as.

As described above, according to the present invention, when manufacturing a fully machined electrode for electrical machining such as electrolytic machining or electric discharge machining using a mother die by the Kamesen method, the machined surface of the electrode is formed during molding of the mother die. A magnetic force generating body is embedded in the mother mold in advance for the pointed uneven portion of the lightning coin body, and cast molding is performed, and the surface of the mother mold is made conductive, and this is used as the mother mold. By making the dragon coins curve, the electric current does not short pass only to flat surfaces and convex curved surfaces, and the magnetic field of the buried magnetic force generator prevents local concentration, is dispersed, is averaged, and flows to the pointed concave parts. Therefore, an excellent effect can be achieved by applying the coins to the entire surface covered with the coin body.

Further, since the magnetic force generating body is simply embedded in the matrix, it has the advantage that it does not affect the peeling of the exposure body or the molding of the dragon body, and it also has the advantage that it can be reused. Furthermore, since the magnetic force generator is buried inside the mother mold rather than outside, it does not get in the way when depositing money into a money tank, and there is no need to worry about short circuits.

[Brief explanation of drawings]

Fig. 1 is a schematic illustration of a processing electrode, Fig. 2 is an illustration of a matrix based on the prior art, Fig. 3 is an explanatory diagram of covering the lightning mirror body on the pointed uneven portion, also based on the prior art, and Fig. 4 The following is an explanatory diagram of one embodiment of this invention, Fig. 4 is an explanatory diagram of a matrix, Fig. 5 is an explanatory diagram of a coin, Fig. 6 is an explanatory diagram of a military registration cover, and Fig. 7 is an explanatory diagram of a pointed recess. FIG. 13...Electric money liquid, 6...Conductivity treatment, 5.
...Material mold, 4...Cusp uneven portion, 7...
...Magnetic force generator. Figure l Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7

Claims (1)

[Claims] 1 In a matrix electroforming method in which electroforming is performed by applying a magnetic field to the pointed uneven portion of the electroformed mother mold immersed in an electroforming solution, a magnetic force is generated in advance within the mother mold of the pointed uneven portion. 1. A method for electroforming a matrix, characterized in that the body is embedded in the body, and during electroforming, the electroforming current is uniformly dispersed and concentrated on the pointed uneven portions so that the electroformed body is coated.