JPS63105881A - Method of cutting diamond for executing invisible insertion, polishing method and machine for executing said method - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Document FR-^-802,327 states that by forming a notch or notch in each ridge that constitutes the lower part of the gemstone, or actually the culet face,
A method of fitting a jewel into a jewel stand has been proposed. According to this description, the incisions in the stone, which are described as serrated, can be of various shapes.

Even though the teachings of the said patents are valid in the case of colored stones, it is not possible to set diamonds in a way that does not actually appear visually. When a notch or notch is formed, the gloss of the polishing table surface appears dull regardless of its shape and position at the ridge, and therefore the inset method described in document FR-8-802,367 cannot be used for diamonds. It is absolutely impossible to do so.

The purpose of the present invention is to eliminate this drawback, and the purpose of the present invention is to form a notch or notch in the ridge of the lower curette surface, and to engage a jewelry stand in this notch or notch. It provides a method for cutting diamonds,
The cutout is characterized in that it is formed in a V-shape with two surfaces that are arranged on either side of the plane of the natural table surface, which is the direction of orientation of the polishing table surface, and that are themselves polished.

In fact, the inventor found that when the two surfaces of the V-shape are polished, the inlaid state of both the metal part engaging the notch and the notch itself is completely hidden, and the shine of the stone is also reduced. I confirmed that nothing has changed.

As is well known, the four-point table plane is parallel to the cubic crystal plane, that is, the plane that passes through the four vertices on the same plane of the octahedron, and the plane that passes through the three vertices on the same plane of the octahedron. It is not possible to polish a diamond along a parallel three-point table surface and a two-point table surface that passes through the two vertices or edges of the octahedron.

Therefore, both polishing table surfaces are cut along the four-point table surface and at least 7 degrees to the four-point table surface.
In the case of so-called perfect stones or stones with saw-cuts in an inclined state, the cuts are made in the table surface at two points, one of the surfaces of each V-shaped surface forming the notch being approximately parallel to the polishing table surface. and the other surface is inclined at least 30° with respect to said one surface.

If the polishing table surface is arranged on a three-point table surface, the cuts are made on a four-point table surface.

If the polishing table surface is tilted onto the two-point table surface, the notch is formed in the two-point table surface.

A cut is first made with a saw or laser, and then a V-shaped surface is sanded with a saw, one side parallel to the polishing table surface and the other at an angle of at least 30'' with respect to said one. The saw carriage supporting the diamond is configured to be movable along a direction parallel to the surface of the abrasive disc, the surface of which is coated with a mixture of diamond shavings and gum arabic diluted with water. The polishing speed of the disk surface against the diamond is 2500 to 3200 a+/min, preferably 2750 to 2900 m/min, and the contact passing frequency of the diamond against the disk surface is about 10 times/min.
n, and the passing speed is 211/in.

The abrasive agent, a mixture of diamond dust and gum arabic, is essential in order not to dull the facets of the V-shaped surface and the table surface during the polishing process.

The relative speed of the abrasive disk surface to the diamond is:
The minimum speed should be greater than 2500 m/m1n (below this speed no polishing will occur) and the maximum speed should be kept below 3200 m/w+in (above this speed diamond combustion will occur) .

Furthermore, since the carriage supporting the diamond should preferably reciprocate about 5 times per minute when the diamond passing speed is about 2 m/iin, the polishing time should be short and there should be a cooling period. .

The invention will now be described in more detail with reference to the accompanying drawings, in which: FIG.

In Ensame Takumi's drawings, reference numeral 1 represents the table surface of the cut diamond, 2 represents the facet surface of the diamond, and 3 represents the culet surface.

According to the present invention, the notch 7 is formed at the ridge of the curette surface. The notch is V-shaped with a ridge 4 perpendicular to the ridge of the curette surface, and one surface 5 of the two V-shaped polishing surfaces is approximately parallel to the table surface 1. and the other surface 6 is approximately 30° between the surface 5 and the other surface 6.
forming an angle.

In the V-shaped crystal octahedron shown in FIG. 4, the plane passing through the four points 10 at the bottom of the pyramid and the plane parallel to the plane are called the four-point table plane. The front table surface 12 passing through the two points 10 and the apex 11 of the pyramid is called a three-point table surface, and the surface passing through the edge 13 of the tetrahedron is called a two-point table surface. The natural table surface can be substantially abrasive due to its hardness, and the cut diamond facets and in particular the table surface 1 have a minimum angle of about 7° with the natural table surface, which is the cutting direction of the facets. should be formed.

In Figure 5, the diamond is cut as a complete stone, and the table surface 1 has at least 7 points on the table surface.
° The incision of the notch 7 is made in the table surface at two points, and then this V-shaped facet surface is ground, the facet surface 5 is approximately parallel to the table surface 1, in other words If so, the 4-point table should be tilted approximately 7 degrees above the table surface. The facets 6 are inclined at approximately 30°.

In the case of a diamond cut at a saw cutting point as shown in FIG. 6, the criteria for forming a notch are the same as in the case of a perfect diamond.

As shown in Fig. 7, in the case of a so-called rough diamond, the table surface 1 has four points on the table surface 10-1.
tilted at least 7° above zero. The notches 7 are formed on the four-point table surface and on the abrasive surface according to the same criteria by forming an angle of at least 7° with the four-point table surface.

In the case of a diamond having a surface inclined on the two-point table surface as shown in FIG. parallel to plane 1, and the other inclined at about 30° with respect to the first plane.

The notches in the notches are sawed or laser cut with a continuous pass of 471000 mm.

Therefore, the V-shaped surface constituting the notch is ground with a saw cutter, and the diamond support of the saw machine is driven by a carriage that is driven to reciprocate in a direction parallel to the surface of the disk of the 1a machine. is attached to. This reciprocating motion has an amplitude of 20 cm and a frequency of 12 seconds, and therefore a speed of 2 m/
min, the frequency of contact passes of the diamond with the disk is 10 times/+nin.

A disk of diameter 15 co+ is driven at a speed of 6000 rpm and its surface is coated with a mixture of diamond dust and gum arabic diluted with water.

[Brief explanation of the drawing]

Fig. 1 is a bottom view of a diamond with a notch according to the present invention, Fig. 2 is a front view, Fig. 3 is a perspective view, and Fig. 4 is a diamond natural crystal octahedron to explain the orientation of the table surface. Figure 5 is an explanatory diagram showing the position of the notch in a diamond cut as a complete stone.
Fig. 6 is an explanatory diagram corresponding to the case of a diamond cut at a saw cutting point, Fig. 7 is an explanatory diagram corresponding to the case of a diamond cut by a rough stone in a cleavage state, and Fig. 8 is an explanatory diagram corresponding to the case of a diamond cut with a rough stone in a cleaved state. FIG. 2 is an explanatory diagram corresponding to the case of a diamond. 1... Polishing table surface, 4... V-shaped surface, 5-6... V-shaped surface, 7... Notch portion.

Claims (8)

[Claims] (1) A diamond cutting method for achieving an invisible fit by using a notch located below the circumferential ridge and engaging a table in the notch, the notch being oriented with respect to the polishing table surface. A method characterized in that it is formed in a V-shape with two surfaces arranged on either side of the plane of the natural table surface which is in the direction and which are themselves polished. (2) Each V-shaped surface forming the notch is characterized in that one of the V-shaped surfaces is substantially parallel to the surface of the polishing table and the other is inclined at least 30 degrees with respect to said one surface. A method according to claim 1. (3) A method applied to so-called perfect stones or stones with saw-cut points, where the polishing table surfaces are both cut along four-point planes and are inclined at least 7 degrees to the four-point table surface. 3. The method according to claim 1, wherein the incisions are formed on the table surface at two points. (4) A method applied to so-called cleaved raw stones or stones placed on a three-point table surface, characterized in that cuts are formed on the four-point table surface.
or the method described in paragraph 2. (5) A method according to claim 1 or 2, which is applied to a stone tilted on a two-point table surface, and the method is characterized in that a notch is formed on the two-point table surface. . (6) The method according to any one of claims 3 to 5, characterized in that the incision is formed by sawing or laser, then its shape is adjusted, and the surface is polished. (7) A modified saw cutting machine for carrying out the method according to any one of claims 1 to 6, wherein the diamond support base is cut along a direction parallel to the surface of the disk. A machine characterized in that it is movably mounted and driven in reciprocating motion along this direction. (8) A polishing method for carrying out the cutting method according to any one of claims 1 to 6 using the machine according to claim 7, the method comprising: A mixture of diamond chips and gum arabic diluted with water is applied to the surface, and the polishing speed of the disk surface against the diamond is 2500 to 3200 m/min, preferably 2750 m/min.
~2900 m/min, the frequency of contact of the diamond with the disk surface is about 10 times/min, and the passing speed is 2 m/min.