DE29921182U1 - Molded element for the production of pouring channels in molds for the production of dental workpieces - Google Patents

Description

PATENT ATTORNEYS Dipl.-lng. A. Wasmeier Dipl.-lng. H. Graf

Authorized before the European Patent Office + Trade Mark Office · Professional Representatives before the European Patent Office + Trade Mark Office

Patent Attorneys PO Box 10 08 26

German Patent and Trademark Office

93008 Regensburg

D-93008 REGENSBURG P.O. BOX 10 08 26

Zweibrückenstr. 12 your message Our sign D-93055 REGENSBURG
GREFLINGERSTRASSE 7 Your Letter Our Ref. Telephone (0941)79 20 85 80297 Munich Sch/g 19,275 (0941)79 20 86
Fax (0941)79 5106 E-mail: wasmeier-graf@t-online.de Your sign Date Your Ref. Date 30 November 1999

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Applicant:

Dental Research Schleicher GmbH
Haidhof commercial area
Ländenstrasse 1
D-93339 Riedenburg

Title:

Form element for producing pouring channels in molds for the production of dental workpieces

Accounts: HypoVereinsbank (bank code 750 200 73) 5 839 300 Place of jurisdiction Regensburg

Postgiroamt München (BLZ. 700 1.0.0 80^.893.^9-801.. . ..... . .A19375.DOC

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Form element for producing pouring channels in moulds for the production of Dental workpieces

The innovation relates to a form element according to the generic term protection claim

When producing casting molds for dental workpieces, such as crowns or bridges, it is necessary to form a section of the wax model that forms a pouring channel, which is also made of wax. Attaching the pouring channel has so far been quite complicated.

The aim of the innovation is to show a mold element for producing the pouring channel, which significantly simplifies the work involved in producing a casting mold. To solve this problem, a pouring channel mold element is designed in accordance with claim 1.

Further developments of the invention are the subject of the subclaims.

The new pouring channel mold element is a prefabricated element that can be used immediately. It is made of a material that is at least somewhat harder than the usual model wax, so that the mold element can be attached to the respective wax model in a particularly simple manner by inserting it with a tip.

The innovation is explained in more detail below using the figures of an example. They show:

Fig. 1 shows a simplified representation of a casting mould for producing dental workpieces made of metal, for example gold;

Fig. 2 in a simplified representation and in side view a forming element for forming the pouring channel according to the innovation.

In Figure 1, an embedding mold for embedding wax models in an investment material for producing casting molds for dental workpieces, such as crowns, bridges, etc. is shown very schematically at 1. Such an embedding mold is described, for example, in DE 299 10 525. It essentially consists of a base part 2 and a wall 3 delimiting an interior of the embedding mold 1 with an additional outer support wall 4 or sleeve. The wall 3 is made of a transparent material, for example a transparent plastic film. The base 2 has a conical projection on the inside of the interior of the embedding mold, which in the embodiment shown is arranged on the same axis as the axis of the cylindrical embedding mold. The model 7 is held on this projection 5 via a holder which forms a later pouring channel and which is designed as a pouring channel mold element 6. The latter is produced in a known manner on a modeling material which melts at higher temperatures, namely wax. To form the casting mold, the interior of the embedding mold 1 is filled with an investment compound 8 so that the model 7 is completely embedded in this compound 8. After the investment compound 8 has hardened, the mold thus produced is removed from the embedding mold 1. The material of the model 7 and the sprue mold element 6 are removed by heating so that a casting cavity with a sprue or runner is created and the casting cavity is connected via this runner to the mold funnel formed by the projection 5.

The special feature is that the casting channel mold element 6 is a prefabricated mold element made of a material that melts or evaporates under the influence of heat and whose hardness is greater than the hardness of the material used for the model 7 (wax). For example, the channel mold element 6 consists of a thermoplastic. The casting channel mold element 6 essentially consists of an elongated, shaft-like body 9, which is provided at one end with a projection or a tip 10 for fastening the model 7, with its other end in the usual way on the projection 5 of the base part

A19275.DOC ... ·

and is provided with an extension 11 in the area of this end.

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List of reference symbols Embedment form 1 Bottom part 2 Perimeter wall 3 Reinforcing wall or sleeve 4 head Start 5 Pouring channel mold element 6 Model 7 Investment material 8th Casting channel mold element body 9 Great 10 extension 11

A19275.DOC

Claims (4)

1. Form element for producing casting channels in molds for the manufacture of dental workpieces, for example crowns or bridges by casting, characterized by an elongated, rod-like body which is provided at one end with at least one tip for attachment to a wax model. 2. Shaped element according to claim 1, characterized in that the shaped body ( 9 ) has an extension ( 11 ) in the region of one end. 3. Mould element according to one of the preceding claims, characterized by its production from an easily meltable or vaporizable material with a greater hardness than wax. 4. Shaped element according to one of the preceding claims, characterized by its production from a thermoplastic material.