JP2630510B2 - Ring manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a ring with a noble metal.

[0002]

2. Description of the Related Art Conventionally, in order to manufacture decorative articles such as rings using noble metals, so-called machined ones, which are produced through processes such as melting, rolling, pressing, cutting, and polishing, are generally used. , These are limited by the processing method.
There was a limit to the three-dimensional design and fine patterns, and the wall thickness could not be reduced. In particular, when platinum is used, the machinability is poor, and the life of the cutting tool is shortened, resulting in an increase in cost.

[0003] On the other hand, there are also a lost wax method and a powder molding method. However, the former requires a lot of labor for mold production and cannot be mass-produced, resulting in high cost, and the latter has pores on the surface.
There is a defect that the surface is slightly clouded and metallic luster cannot be obtained, and the aesthetic appearance is impaired as a decorative product.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to improve the above-mentioned disadvantages of the conventional product, to provide good cutting properties and to provide an injection molding
With no pores on the surface from molded products mass-produced at
And a method of forming a ring of each size .

[0005]

According to the present invention, a ring is kneaded with a binder made of a powdered noble metal and a thermoplastic resin, and the kneaded material is subjected to injection molding, debinding, and sintering. After performing the process to produce a ring-shaped molded product , a holding member is applied to the inner peripheral surface of the molded product , and
Pressing and rotating by applying a roll to the opposing outer peripheral surface
Therefore, the ring is expanded and formed into rings of each size
It is manufactured by a method.

[0006] In the present invention, the powder noble metals gold or gold alloy, platinum or platinum alloy, silver or a silver alloy, combinations thereof, or a combination of these and other metal is used, the powder noble metal in the mixed powder, an alloy powder Good .

In the present invention, a concave portion is formed in a surface layer of a molded article.
And dissolve other different noble metal in it,
Expanded with a roll to form rings of each size
And a ring combining patterns of different colors. Also,
Dissolve the low melting point metal in the recess and roll it into the roll
After expanding to form rings of each size, low melting
When melting the point metals only removed, the rings of complex uneven pattern of three-dimensional is directly appear in the surface layer.

[0008]

By manufacturing the ring as described above, the same
If mass production of ring-shaped molded products with dimensions is necessary,
Can make any desired size of the ring
Significant cost reduction. At the same time, the surface of the ring is low.
The surface of the pores
Because it is crushed neatly, the surface condition there is machined
You can maintain almost the same aesthetics as the ones. Furthermore, like platinum
Even difficult-to-cut materials have improved machinability after forming and have lost
The fineness of the carving is as deep as the wax method.
Patterns are also available.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the process chart of FIG.

(Example 1) 90% of platinum powder having a particle size of 20 μm or less and palladium powder having a particle size of 20 μm or less 1
The mixture was mixed with a thermoplastic resin as a binder by a kneader to form granular pellets, and the pellets were injection-molded by an injection machine to prepare a prototype ring. Next, the original shape of the ring is heated to 450 ° C. at a rate of 8 ° C./H in the air atmosphere, and the binder is removed at 450 ° C. for 2 hours, and then removed in a vacuum atmosphere. Sintering was performed at 2 ° C./2H to obtain a molded product of a ring. After cutting off the shoulders and the like of this molded product by cutting, a core metal is applied to the inner peripheral surface of the molded product, and a roll is applied to the outer peripheral surface opposite to the core metal to press and rotate. Of each size were obtained. A pattern was cut into the molded product of the ring by diamond cutting, and the inner surface was polished to obtain a finished ring product.

[0011] Compared with the ring obtained in this embodiment and a conventionally machined ring, the metallic luster on the surface of the ring is almost the same visually, and even when viewed with a magnifying lens, the surface layer of the ring is formed by rolling. The pores can hardly be confirmed because they are crushed. Also, in cutting with a diamond cutting machine, the conventional product requires about 450 to cut the entire ring surface.
The cutting tool had to be changed by processing one ring, but in this example, up to about 700 processing could be performed.

(Example 2) A pellet was prepared in the same manner as in Example 1, and an original ring shape was obtained by injection molding. The original shape of this ring is injection-molded using a mold that has been processed in advance so as to have a design with irregularities on the surface, similar to lost wax. Next, the gold alloy (1) was inserted into the concave portion of the molded product of the ring obtained by performing binder removal and sintering under the same conditions as in Example 1.
8K) is melted, the surface of the ring is cut with a diamond bit, and roll expansion molding is performed in the same manner as in Example 1. Thereafter, only the gold alloy portion of the molded product is etched and honed to form a ring. As a finished product, a combination of platinum and gold with a complex pattern of vertical and horizontal was obtained.

Example 3 A pellet was prepared in the same manner as in Example 1, and an original ring shape was obtained by injection molding. The original shape of this ring is injection molded with a mold that has a three-dimensionally carved deep three-dimensional appearance on the surface, as well as lost wax, and that has been pre-processed to form a complex, finely uneven design pattern. . Next, a wood alloy, which is a low melting point alloy, was melted into a concave portion of a molded product of a ring obtained by performing binder removal and sintering under the same conditions as in Example 1, and then cooled and solidified. Roll expansion molding is performed as described above, and thereafter, heat above the melting point of the wood alloy is applied to melt and remove only the wood alloy, and the ring has a three-dimensional three-dimensional complex and fine design pattern on the surface. The finished product was obtained.

The comparison between the rings obtained in Examples 2 and 3 and the conventional product is almost the same as the comparison in Example 1.

Example 4 A gold alloy (18K) powder having a particle size of 45 μm or less as a precious metal powder and a thermoplastic resin as a binder are kneaded with a kneader to form granular pellets, and the pellets are injection-molded by an injection machine. The original shape of the ring was made. Next, the original form of this ring was placed in an argon atmosphere at a rate of 10 ° C./H at a heating rate of 450 ° C.
Temperature to 450 ° C and 2H capping at 450 ° C to remove binder
After that, sintering was performed at 950 ° C./3H in a hydrogen atmosphere to obtain a molded product of a ring. Thereafter, roll expansion molding was performed in the same manner as in Example 1 to obtain molded articles of desired ring sizes. The molded product of this ring was cut and polished by diamond cutting to obtain a finished ring product.

Example 5 A silver alloy (starring silver) powder having a particle size of 45 μm or less as a precious metal powder and a thermoplastic resin as a binder are kneaded with a kneader to form granular pellets. Injection molding was performed to produce a prototype ring. Next, the original shape of the ring is heated at a rate of 10 ° C./H in a nitrogen atmosphere, and is bound at 450 ° C. for 2 hours to remove the binder. To obtain a molded ring. Thereafter, roll expansion molding was performed in the same manner as in Example 1 to obtain molded articles of desired ring sizes. The molded product of the ring was further cut and polished with a diamond cut to obtain a finished ring product.

The comparison between the rings obtained in Examples 4 and 5 and the conventional product is almost the same as the comparison in Example 1 except for the cutting tool exchange during cutting.

[0018]

According to the present invention, a ring-shaped molded article having the same dimensions can be used for
If you have mass production, you can use each desired size ring when you need it
Because it can be made arbitrarily, it greatly reduces costs
You. At the same time, the surface layer of the ring is rolled and expanded.
The pores on the surface layer are crushed neatly
And the surface condition there is almost the same aesthetic appearance as the machined one
Can be kept. Furthermore, even difficult-to-cut materials such as platinum
Improved machinability and about the same as lost wax method
You can also create fine patterns with a deeply carved three-dimensional effect.
And so on.

[Brief description of the drawings]

FIG. 1 is a process chart showing an embodiment of the present invention.

 ──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-63-223103 (JP, A)

Claims (3)

(57) [Claims] 1. A kneaded powder noble metal and a binder made of a thermoplastic resin, and the kneaded product is subjected to injection molding, binder removal,
After performing each process of sintering to produce a ring-shaped molded product,
A holding member is applied to the inner peripheral surface of the molded product, and is opposed to the holding member.
By applying a roll to the outer peripheral surface and pressing and rotating,
A method for manufacturing a ring, comprising expanding a ring to form a ring of each size . 2. The powdered noble metal is platinum or a platinum alloy.
The molded product has a concave portion in the surface layer portion and another different color there.
Dissolve precious metal and expand it with the roll
The method for manufacturing a ring according to claim 1, wherein the ring is formed into rings of various sizes . 3. The molded product is provided in a concave portion provided in a surface portion thereof.
Dissolve low melting metal and expand it with the roll
After processing to form rings of each size, the low melting point metal
2. The method according to claim 1, wherein only the material is melted and removed.
Or the manufacturing method of the ring of 3.