EP2853170B1 - Plastic body and method for inserting a decorative stone into a plastic body - Google Patents

Description

The invention relates to a plastic body of a plastic material, in which at least one gemstone is thermally inserted under material displacement, according to the preamble of claim 1.

The invention further relates to a method for inserting a gemstone in a plastic body made of a plastic material, according to claim 8.

A generic prior art is known from FR 1 120 802 A known. A gemstone is pressed into a plastic body, with an annular bead is formed as a socket.

It is known to apply gemstones as decor on plastic workpieces. By a gemstone decor, the value of such an item can be significantly increased. From the DE 38 20 250 A1 or the DE 41 04 337 A1 Various methods are known in which gems are introduced by means of a special bonding layer in recesses of a workpiece and held therein. The use of separate connecting layers is complex in terms of production, wherein, moreover, the connecting layer can impair the visual impression of the workpiece surface.

From the DE 201 12 975 U1 or the DE 100 35 158 A1 are versions for gems known which have a separate encompassing retaining element. These brackets are technically complex and can the affect visual impression of the gemstone and thus decorated object.

Another gemstone bezel made of metal is the GB 2 079 140 A to denemen.

From the DE 1 079 872 goes out a plastic body in which heated gemstones are pressed into the thermoplastic resin of the carrier work piece. For improved connection it is taught to provide on the gemstone a coating layer which forms a firm connection to the workpiece during insertion. The application of such an adhesive layer is complicated.

In addition, adhesive coatings depending on the environmental conditions are subject to aging processes, which lead to a weakening of the adhesive bond and cause the risk of loosening the gemstone. In the case of a décor with a multitude of gemstones, the absence of a gemstone is perceived as disturbing, as a result of which the quality of the decorated object is damaged.

The invention has for its object to provide a plastic body and a method for inserting a gemstone in a plastic body, which allow easy production and a reliable connection between the gemstone and the plastic body and at the same time the visual effect of the gemstone is particularly well.

The invention is achieved on the one hand by a plastic body having the features of claim 1 and on the other hand by a method having the features of claim 8. Preferred embodiments of the invention are specified in the respective dependent claims.

In the plastic body according to the invention it is provided that from the displaced plastic material around the gemstone an annular socket is formed, through which the gem is held at least positively and which has along its top a circumferential contour with projections and depressions.

A first aspect of the invention is to insert the gemstone under pressure and temperature effect in the plastic material, wherein an annular socket for positive retention of the gemstone is formed by the displaced plastic material. The gemstone is thus mechanically held by gripping the plastic body. In this case, the annular socket is formed integrally with the plastic body. Thus, the gemstone without an additional adhesive layer reliably attached to the plastic body for a long period of time. In certain cases, however, an additional adhesive layer may also be provided.

tion and further reduces the perceptibility of the version. Thus, a gemstone on the plastic body for a secure and reliable attachment is particularly good effect.

A particularly harmonious overall impression is achieved according to the invention in that the peripheral contour is formed as a uniform wave or arc contour.

This can be achieved according to a further embodiment of the invention in particular by the fact that the number of elevations and recesses is tuned to a number of facets of gemstone. The gemstone can have almost any arbitrary cut, especially a brilliant cut. In principle, the gemstone according to the invention may be any gemstone or semi-precious stone. In particular, the gemstones may be so-called "imitation stones", which are made for example of a zirconia material, a glass material or another thermally solid decorative material.

For a particularly stable insertion of the gemstone, it is advantageous according to a variant of the invention that the gemstone is provided with a conical insertion. The insertion tube can also be provided with a cut as a lower part of the gemstone, whose facets contribute to the light reflection of the gemstone altogether.

To form a defined contour on the annular socket, it is basically provided that the contour of the socket is subsequently formed by means of a molding tool. In particular, the desired contour can be embossed into the still plastically deformable plastic material via an annular die.

A particularly advantageous embodiment of the invention is that the contour is formed exclusively when inserting the gem. By appropriate design of the Einfügefußes and a corresponding adjustment of the insertion conditions as a function of the material used, a formation of the wave or arcuate contour when inserting or pressing the gemstone can be achieved in the plastic body. This contouring when defined displacement of the plastic material is a special created a uniform surface, which supports the light reflection effect. Decisive for the formation of the contour during insertion is a specific velocity profile, taking into account pressure and temperature during the insertion movement, in order to effect a uniform material displacement around the gemstone.

The formation of the contour basically depends on the cut and the number of facets of the inserted gemstone. A particularly harmonious overall impression of gemstone and surrounding frame is achieved in accordance with a preferred embodiment of the invention in that a height difference between the elevations and the recesses of the contour between 0.05 mm and 1 mm, preferably between 0.1 mm and 0.5 mm is.

It is particularly preferred according to the invention that the socket has a height between 0.2 mm and 2 mm. The width of the socket can also be between 0.1 mm and 2 mm. Overall, this achieves a particularly restrained optical effect of the annular socket.

In the inventive method for inserting a gemstone in a plastic body made of a thermoplastic material is provided that the gemstone is pressed under heat in the plastic body, wherein plastic material is plastically deformed and displaced, and with the displaced plastic material around the gemstone an annular socket is formed , by which the gemstone is held at least positively and which has along its top a circumferential contour with elevations and recesses.

With this method, in particular, the above-described plastic body can be produced with at least one gemstone. The plastic body is preferably made of a thermoplastic material which may be, for example, PA, PP, PMMA or another thermoplastic. However, it is also possible to use a duroplastic or an elastomer, wherein the insertion can take place before curing.

In principle, it is possible to heat the plastic material directly to a temperature at which it is plastically deformable. A preferred embodiment the invention is that the gemstone is heated to a temperature between 150 ° C and 400 ° C prior to insertion. The temperature depends on the softening temperature of the thermoplastic material, the starting temperature of the plastic part and the heat absorption capacity of the gem to be heated.

In principle, it is conceivable that the gemstones are inserted by hand into the plastic material. However, it is difficult to form a fine annular socket for a reliable hold of the gemstone. According to the invention, it is therefore preferred that a press-fit with a suction channel is used, via which a gem is picked up by means of negative pressure and held it at least until the beginning of the insertion step. With such a press-in punches, which is positioned manually or by means of handling unit computer-controlled or hand-driven, a reliable reproducible insertion of the gemstone and forming the desired version can be achieved by material displacement. By picking up the gemstone on the press-in punch by means of negative pressure, a reliable hold even very small gemstones, which have a diameter in the range of 1 to 3 mm, also allows.

It is advantageous according to a further process variant of the invention that the press-fit is heated. In particular, in the case of relatively small gemstones, it is thus ensured that the gemstones have sufficient heat during the insertion process. A reliable melting or softening of the plastic material and the desired material displacement with a flow of material along the warm side surfaces of the gemstone are guaranteed.

Fig. 1:

eine schematische Teilquerschnittsansicht durch einen erfindungsgemäßen Kunststoffkörper mit Schmuckstein;

Fig. 2:

eine Draufsicht auf den Kunststoffkörper mit Schmuckstein gemäß Fig. 1;

Fig. 3:

eine ausgeschnittene Querschnittsansicht entlang eines Teiles der ringförmigen Fassung; und

Fig. 4:

eine Draufsicht auf ein Unterteil des Schmucksteins gemäß Fig. 1.

The invention will be further explained with reference to a preferred embodiment, which is shown schematically in the drawings. In the drawings show:

Fig. 1:

a schematic partial cross-sectional view through a plastic body according to the invention with gemstone;

Fig. 2:

a plan view of the plastic body with gemstone according to Fig. 1 ;

3:

a cut-away cross-sectional view along a portion of the annular socket; and

4:

a plan view of a lower part of the gem according to Fig. 1 ,

According to Fig. 1 a gemstone 20 is thermally inserted according to the invention in a plate-shaped plastic body 10. The non-cutting penetration of the heated gemstone 20 in the thermoplastic material of the plastic body 10 plastic material is softened and displaced along the heated outside of the gemstone up to the free top of the plastic body 10. According to the invention an annular socket 12 is formed from the displaced plastic material, which in particular from Fig. 2 is apparent. The annular socket 12 surrounds a lateral edge 22 which extends in an annular manner around the gemstone 20 and separates a top part 21 from a bottom part 23. The upper part 21 and the lower part 23 are formed with a ground 24, through which numerous facets 26 are formed on the surface of the gemstone 20. The lower part 23 is designed as an approximately conically shaped insertion tube 28.

The annular socket 21 surrounds, as seen from Fig. 1 can be seen, the annular edge 22 circumferentially, so that the gemstone 20 is positively held and thus stable on the plastic body 10 without an adhesive attachment. To support the light reflections and the play of light of the ground gemstone 20, a contour 16 along the annular socket 12 is adapted to the ground 24 formed. This contour 16 is formed in the illustrated embodiment as an arc contour with regular elevations 17 and intervening recesses 18, in particular Fig. 3 can be seen. In the present embodiment, the elevations 17 and depressions 18 are arranged corresponding to the number of ground edges between the facets 26 which intersect the annular edge 22.

Overall, a narrow and thus less conspicuous stable version 12 is created around the gemstone 20 around so by the invention. Due to the contouring of the annular socket 12, the annular socket is less disturbing and may even support the play of light of the gemstone 20.

Claims (13)

1. Plastic body consisting of a plastic material, into which at least one gemstone_(20) is inserted thermally through material displacement,
   out of the displaced plastic material an annular setting (12) is formed around the gemstone (20), through which the gemstone (20) is at least held in a form-closed manner,
   characterized in that
   along its upper side the setting (12) has a circumferential contour (16) with elevations (17) and depressions (18) and
   in that the circumferential contour (16) is designed as a uniform wavy or curved contour.
2. Plastic body according to claim 1,
   characterized in that
   a laterally projecting edge (22) of the gemstone (20) is clasped circumferentially by the annular setting (12).
3. Plastic body according to claim 1 or 2,
   characterized in that
   the circumferential contour (16) of the setting (12) matches a cut (24) of the gemstone (20).
4. Plastic body according to any one of claims 1 to 3,
   characterized in that
   the number of elevations (17) and depressions (18) matches a number of facets (26) of the gemstone.
5. Plastic body according to any one of claims 1 to 4,
   characterized in that
   the gemstone (20) is provided with a conical insertion base (28).
6. Plastic body according to any one of claims 1 to 5,
   characterized in that
   a height difference between the elevations (17) and the depressions (18) of the contour (16) ranges between 0.05 mm and 1 mm, preferably between 0.1 mm and 0.5 mm.
7. Plastic body according to any one of claims 1 to 6,
   characterized in that
   the setting (12) has a height of between 0.2 mm and 2 mm.
8. Method for inserting a gemstone (20) into a plastic body (10) consisting of a plastic material, in which

   - the gemstone (20) is pressed under the effect of heat into the plastic body (10), whereby plastic material is plastically deformed and displaced, and

   - with the displaced plastic material an annular setting (12) is molded around the gemstone (20), through which the gemstone (20) is at least held in a form-closed manner,
   characterized in that

   - along its upper side the setting (12) is designed with a circumferential contour (16) with elevations (17) and depressions (18) and

   - in that the circumferential contour (16) is designed as a uniform wavy or curved contour.
9. Method according to claim 8,
   characterized in that
   before insertion the gemstone (20) is heated to a temperature ranging between 150 °C and 400 °C.
10. Method according to claim 8 or 9,
    characterized in that
    a press-in die with a suction channel is used, by which a gemstone (20) is received by means of low pressure and held thereon at least until the beginning of the insertion step.
11. Method according to claim 10,
    characterized in that
    the press-in die is heated.
12. Method according to any one of claims 8 to 11,
    characterized in that
    the contour (16) of the setting (12) is molded subsequently by means of a molding tool.
13. Method according to any one of claims 8 to 11,
    characterized in that
    the contour (16) is designed solely during insertion of the gemstone (20).

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